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Quality Assurance Poses Challenges for Market Participants' which was 
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Report to Congressional Requesters: 

United States Government Accountability Office: 

GAO: 

August 2008: 

Carbon offsets: 

The U.S. Voluntary Market Is Growing, but Quality Assurance Poses 
Challenges for Market Participants: 

GAO-08-1048: 

GAO Highlights: 

Highlights of GAO-08-1048, a report to congressional requesters. 

Why GAO Did This Study: 

Carbon offsets—reductions of greenhouse gas emissions from an activity 
in one place to compensate for emissions elsewhere—are a way to address 
climate change by paying someone else to reduce emissions. To be 
credible, an offset must be additional—it must reduce emissions below 
the quantity emitted in a business-as-usual scenario—among other 
criteria. Assessing credibility is inherently challenging because it is 
difficult to make business-as-usual projections. Outside the U.S., 
offsets may be purchased on compliance markets to meet requirements to 
reduce emissions. In the U.S., there are no federal requirements and 
offsets may be purchased in the voluntary market. GAO was asked to 
examine (1) the scope of the U.S. voluntary carbon offset market, 
including the role of the federal government; (2) the extent to which 
mechanisms for ensuring the credibility of offsets are available and 
used and what, if any, related information is shared with consumers; 
and (3) trade-offs associated with increased oversight of the U.S. 
market and including offsets in climate change mitigation policies. 
This report is based on analysis of literature and data, interviews 
with stakeholders, and GAO’s purchase of offsets. 

What GAO Found: 

The scope of the U.S. voluntary carbon offset market is uncertain 
because of limited data, but available information indicates that the 
supply of offsets generated from projects based in the United States is 
growing rapidly. Data obtained from a firm that analyzes the carbon 
market show that the supply of offsets increased from about 6.2 million 
tons in 2004 to about 10.2 million tons in 2007. Over 600 organizations 
develop, market, or sell offsets in the United States, and the market 
involves a wide range of participants, prices, transaction types, and 
projects. The federal government plays a small role in the voluntary 
market by providing limited consumer protection and technical 
assistance, and no single regulatory body has oversight 
responsibilities. 

Figure: U.S. Supply of Voluntary Offsets by Volume and Number of 
Projects from 2000 through 2007: 

This figure is a combination line and bar graph showing U.S. supply of 
voluntary offsets by volume and number of projects from 2000 through 
2007. The line represents the volume (metric tons of carbon dioxide 
equivalent) and the bar represents the number of projects. The X axis 
represents the year, and the Y axis represents the number. 

Year: 2000; 
Volume: 1.21995; 
Number of project: 13. 

Year: 2001; 
Volume: 1.23119; 
Number of project: 29. 

Year: 2002; 
Volume: 2.58851; 
Number of project: 48. 

Year: 2003; 
Volume: 5.5488; 
Number of project: 69. 

Year: 2004; 
Volume: 6.16805; 
Number of project: 93. 

Year: 2005; 
Volume: 8.402; 
Number of project: 113. 

Year: 2006; 
Volume: 11.065; 
Number of project: 180. 

Year: 2007; 
Volume: 10.209; 
Number of project: 211. 

[See PDF for image] 

Source: GAO analysis of Point Carbon data. 

[End of figure] 

A variety of quality assurance mechanisms, including standards for 
verification and monitoring, are available and used to evaluate 
offsets, but data are not sufficient to determine the extent of their 
use. Information shared with consumers on credibility is also limited. 
Participants in the offset market face challenges ensuring the 
credibility of offsets, including problems determining additionality, 
and the existence of many quality assurance mechanisms. GAO, through 
its purchase of offsets, found that the information provided to 
consumers by retailers offered limited assurance of credibility. 

Increased federal oversight of the U.S. voluntary market could enhance 
the market’s transparency and improve consumer protection, but may also 
reduce flexibility, increase administrative costs, and stifle 
innovation, according to certain stakeholders. Including offsets in 
regulatory programs to limit greenhouse gas emissions could also lower 
the cost of compliance, according to recent EPA analyses and economic 
literature. However, some stakeholders said that concerns about the 
credibility of offsets could compromise the environmental integrity of 
a compliance system. 

What GAO Recommends: 

GAO is not recommending executive action. However, as it considers 
legislation that allows the use of offsets for compliance, Congress 
might consider, among other things, directing the establishment of 
standardized quality assurance mechanisms. 

To view the full product, including the scope and methodology, click on 
[hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-08-1048. For more 
information, contact John B. Stephenson at (202) 512-3841 or 
stephensonj@gao.gov. 

[End of section] 

Contents: 

Letter: 

Results in Brief: 

The U.S. Voluntary Market Is Growing Rapidly with Limited Federal 
Oversight: 

A Variety of Quality Assurance Mechanisms Are Available and Used, but 
Information on the Credibility of Offsets Is Limited: 

Both Increased Federal Oversight and the Use of Offsets in Climate 
Change Policies Involve Trade-offs between Cost and Credibility: 

Concluding Observations: 

Matter for Congressional Consideration: 

Appendix I: Objectives, Scope, and Methodology: 

Appendix II: Description of Offset Project Types: 

Appendix III: Volume and Number of Offset Projects by State in 2007: 

Appendix IV: Description of the Purchase of Carbon Offsets by the Chief 
Administrative Officer of the House of Representatives: 

Appendix V: Summary of Stakeholder Responses to Interview Questions: 

Appendix VI: Summaries of Selected International, Regional, and State 
Programs: 

Appendix VII: Selected Carbon Offset Standards: 

Appendix VIII: GAO Contact and Staff Acknowledgments: 

Tables: 

Table 1: U.S. Project Types by Number, Volume, and Percentage of Total 
Supply in 2007: 

Table 2: Descriptions of Selected Additionality Tests: 

Table 3: Stakeholders' Rating of Carbon Offset Market Challenges: 

Table 4: Stakeholders' Rating of Characteristics of Offset Credibility: 

Table 5: Stakeholders' Rating of the Credibility of Different Types of 
Carbon Offset Projects: 

Figures: 

Figure 1: Hypothetical Depiction of Offset Project Measured against 
Business-as-Usual Scenario: 

Figure 2: Generalized Carbon Offsets Supply Chain: 

Figure 3: Common Offset Project Types: 

Figure 4: U.S. Supply of Offsets by Volume and Number of Projects from 
2000 through 2007: 

Figure 5: U.S. Offset Supply by Type of Project in 2007: 

Figure 6: Volume and Number of Offset Projects by State in 2007: 

Figure 7: Quality Assurance Mechanisms in a Simplified Carbon Offset 
Supply Chain: 

Abbreviations: 

CAOU: U.S. House of Representatives Office of the Chief Administrative 
Officer: 

CCBS: Carbon Capture and Biological Storage: 

CCGS: Carbon Capture and Geological Storage: 

CCX: Chicago Climate Exchange: 

CFTC: Commodity Futures Trading Commission: 

DEFRA: United Kingdom Department for Environment, Food, and Rural 
Affairs: 

ECM: Exempt Commercial Market: 

EIA: Energy Information Administration: 

EPA: Environmental Protection Agency: 

EU: European Union: 

FTC: Federal Trade Commission: 

FWS: U.S. Fish and Wildlife Service: 

NFF: National Forest Foundation: 

REC: Renewable Energy Certificate: 

UK: United Kingdom: 

USDA: United States Department of Agriculture: 

United States Government Accountability Office: 

Washington, DC 20548: 

August 29, 2008: 

Congressional Requesters: 

Carbon offsets provide a way for individuals, businesses, and 
governments to address concerns about the impact of their greenhouse 
gas emissions on the earth's climate by paying others to undertake 
activities that reduce, avoid, or sequester greenhouse gases.[Footnote 
1] A carbon offset can be defined as a measurable reduction of 
greenhouse gas emissions from an activity or project in one location 
that is used to compensate for emissions occurring elsewhere. For 
example, a U.S. manufacturer might offset its emissions by funding an 
external project that captures methane, a greenhouse gas emitted from 
agricultural sources and landfills. The emissions reduced, avoided, or 
sequestered by such projects are collectively termed carbon offsets, 
though they may involve different greenhouse gases.[Footnote 2] 

Carbon offsets are a potentially attractive option for those interested 
in addressing concerns about climate change because they can offer a 
potentially low-cost and convenient means of reducing, avoiding, or 
sequestering greenhouse gas emissions relative to other options, such 
as altering manufacturing processes or using less fossil fuel.[Footnote 
3] At the same time, consumers of offsets need assurance that buying an 
offset has the same effect on emissions as if they had decided to 
reduce emissions on their own. Providing this assurance is inherently 
challenging because it involves measuring the reductions achieved 
through an offset project against a projected baseline of what would 
have occurred in its absence. For example, if a facility that emitted 
200 tons of carbon dioxide per year implemented a project that reduced 
its emissions by 100 tons, it may have created 100 tons of offsets. See 
figure 1 for a hypothetical depiction of an offset project measured 
against a projected business-as-usual scenario. 

Figure 1: Hypothetical Depiction of Offset Project Measured against 
Business-as-Usual Scenario: 

This figure is an illustration hypothetical depiction of offset project 
measured against business-as-usual scenario. 

[See PDF for image] 

Source: GAO. 

Notes: Business-as-usual emissions could be stable, increase, or 
decrease over time depending upon the source. 

The shaded area in the diagram represents carbon offsets generated from 
the project. 

[A] Emissions reductions from an offset project could occur immediately 
or gradually over time, depending upon the project type. 

[End of figure] 

Although definitions differ, our review of literature and discussions 
with stakeholders identified four general criteria for credible 
offsets: They must be additional, quantifiable, real, and permanent. A 
carbon offset project is generally considered "additional" if it 
decreases emissions of greenhouse gases below the quantity that would 
have been emitted in a projected business-as-usual scenario. 
"Quantifiable" means the reductions can be measured, and "real" means 
the reductions can be verified. "Permanent" means the emissions 
reduced, avoided, or sequestered by a project will not be released into 
the atmosphere in the future. In addition, it is important to ensure 
that double-counting of a particular offset does not occur, where 
multiple purchasers use the same offset. Participants in the offset 
market may use a variety of quality assurance mechanisms to 
substantiate the credibility of offsets. Market participants may also 
track the sale and ownership of offsets by using one of several 
registries. The use of a registry may help participants share details 
about offsets available for purchase on the market. 

Participants in the offset market include project developers, who 
identify and perform actions that reduce, avoid, or sequester 
emissions; third party verifiers, who ensure that projects adhere to 
relevant quality assurance mechanisms; intermediaries, including 
aggregators, who buy offsets and bundle them into larger quantities for 
resale; and retailers, who market and sell offsets to consumers, 
including organizations and individuals. Other participants include 
brokers and exchanges, which facilitate transactions between buyers and 
sellers. Participants may play multiple roles. For example, a single 
company may develop projects, purchase offsets from other developers, 
and market offsets to consumers. Project developers may also skip steps 
in the supply chain and sell directly to consumers. Figure 2 
illustrates a generalized carbon offsets supply chain. 

Figure 2: Generalized Carbon Offsets Supply Chain: 

This figure is a diagram showing generalized carbon offsets supply 
chain. 

[See PDF for image] 

Source: GAO based on Ricardo Bayon, Amanda Hawn, and Katherine 
Hamilton, Voluntary Carbon Markets. 

Note: Dashed boxes illustrate optional steps. Quality assurance 
mechanisms may be employed at multiple stages of the supply chain. 

[End of figure] 

Some carbon offsets are purchased by entities that are subject to legal 
requirements to decrease their greenhouse gas emissions, such as the 
European Union's (EU) Emissions Trading Scheme.[Footnote 4] In such 
cases, the market for offsets is referred to as a "compliance market." 
In contrast, the U.S. market is a "voluntary market," and purchasers 
are not required to limit their emissions or purchase offsets. However, 
the Congress is considering several proposals for limiting greenhouse 
gas emissions that would enable regulated entities to rely, in part, on 
offsets for compliance in a fashion similar to the European Union's 
program. Offsets also may play a role in U.S. state and regional 
programs that are under development. A brief description of certain 
international and domestic programs is provided in appendix VI. 

In the United States, market participants may purchase offsets through 
the Chicago Climate Exchange (CCX) and on the retail market, which 
includes transactions that occur outside of a formal exchange. CCX is a 
voluntary greenhouse gas reduction and trading system through which 
members make legally binding commitments to reduce their 
emissions.[Footnote 5] In addition to these members, the CCX platform 
is also available to offset providers, who may register tons on CCX 
that represent various greenhouse gas reduction projects. CCX 
participants may trade offsets generated from qualifying emissions 
reduction projects. According to CCX, to verify the validity of offsets 
offered for sale on the exchange, and ensure that the underlying offset 
projects conform to CCX rules, all tons registered for sale have been 
verified by approved third party verification firms that are 
specialized in particular fields. Further, in addition to other quality 
assurance procedures, CCX market participants use a registry to help 
track purchases and sales of offsets acquired or sold on the exchange. 
In contrast to exchange trading, which occurs through platforms 
designed to facilitate trades on a larger scale, retail sales typically 
involve transactions directly between two parties. However, certain 
retailers buy offsets through CCX and retire them on behalf of 
consumers.[Footnote 6] In addition, offsets may be bought and sold 
across international borders and through Web sites. 

In this context, you asked us to (1) describe the scope of the U.S. 
voluntary carbon offset market, including the role of the federal 
government; (2) analyze the extent to which mechanisms for ensuring the 
credibility of voluntary carbon offsets are available and used, and 
what, if any, related information is shared with consumers; and (3) 
assess the trade-offs associated with increasing the federal oversight 
of the U.S. voluntary carbon offset market and incorporating offsets 
into broader climate change mitigation policies. 

In conducting our work, we reviewed available government and trade 
literature related to carbon offset markets and conducted 
semistructured interviews with nonprobability samples of stakeholders, 
including providers, third party verifiers, and other knowledgeable 
stakeholders[Footnote 7]. To respond to the first objective, we 
interviewed officials responsible for offset-related programs at the 
departments of Agriculture (Forest Service), Energy (Energy Information 
Administration), and Interior (U.S. Fish and Wildlife Service), as well 
as the Commodity Futures Trading Commission (CFTC), the Environmental 
Protection Agency (EPA), the Federal Trade Commission (FTC), and the 
U.S. House of Representatives Office of the Chief Administrative 
Officer (CAO). We also met with, among others, representatives of the 
Council on Environmental Quality and officials responsible for managing 
state and regional greenhouse gas mitigation programs. To obtain 
detailed information about carbon offset projects in the United States, 
we purchased and analyzed data from Point Carbon, a provider of 
independent carbon market news, analysis, and consulting 
services[Footnote 8]. We assessed the reliability of these data and 
determined that they were sufficiently reliable for the purposes of 
this report. In addition, to respond to the second objective, we 
purchased offsets from a nonprobability sample of retail providers and 
analyzed the materials we received in return as well as information 
provided on Web sites. To respond to the third objective, we reviewed 
available economic literature and information collected through 
stakeholder responses to semistructured interview questions. A more 
detailed description of our scope and methodology is presented in 
appendix I. We conducted our work from July 2007 to August 2008. 

Results in Brief: 

The scope of the U.S. voluntary carbon offset market is uncertain 
because complete data on the volume of transactions do not exist, but 
available information shows that the supply of offsets generated from 
projects based in the United States is growing rapidly. In addition, 
the role of the federal government in the market is generally limited 
to certain consumer protection and technical assistance efforts, 
although several agencies facilitate offset projects or purchase 
offsets as part of efforts to address the environmental impacts of 
their operations. Over 600 entities develop, market, or sell offsets in 
the United States, and the exchange of offsets may involve a wide range 
of participants, prices, transaction types, and projects. Data on the 
total volume of offsets traded in the United States are not available 
and the market's transparency is limited. Despite the lack of complete 
data on the overall volume of transactions, available data show a 
significant increase in the supply of offsets generated in the United 
States. Specifically, the supply has increased approximately 66 
percent, from about 6.2 million tons in 2004 to about 10.2 million tons 
in 2007. Furthermore, the supply is concentrated in a handful of 
states--projects in Texas and Virginia accounted for 34 percent of the 
total volume in 2007--and about 49 percent of the offsets were 
generated from projects that involved methane, a potent greenhouse gas. 
While data on the average price of offsets paid by U.S. consumers were 
not available, prices paid on the global market ranged from $1.83 per 
ton to $306 per ton in 2007, with a volume-weighted average of $6 per 
ton, according to a 2007 report by two market research organizations. 
The federal government plays a small role in the voluntary market, and 
no single regulatory body has oversight responsibility. The CFTC, EPA, 
and FTC, among others, have undertaken some consumer protection and 
technical assistance efforts. In addition, the Forest Service and the 
Fish and Wildlife Service are involved in partnerships that may result 
in the generation of offsets on public lands, and the Chief 
Administrative Officer of the House of Representatives has purchased 
offsets as part of the House's efforts to address its environmental 
impacts. While federal oversight is limited, offset transactions are 
subject to applicable state fraud and consumer protection laws, which 
are generally enforced by each state's attorney general. 

A variety of quality assurance mechanisms are available and used in the 
U.S. voluntary offset market, but the extent of their use is uncertain. 
In addition, our purchase of offsets from a nonprobability sample of 
retailers found that the information given to consumers provided 
limited assurance of credibility. Available data show that many carbon 
offsets in the voluntary market were subject to some quality assurance 
mechanisms, but the data are not sufficient to determine the extent of 
their use. The available information suggests that fewer providers use 
registries to track the ownership and disposition of offsets than use 
third party verification or other quality assurance mechanisms. 
Participants in the offset market face several challenges to ensuring 
the credibility of offsets, including problems determining 
additionality, and the existence of many quality assurance mechanisms 
for verification and monitoring. The lack of comprehensive data on the 
use of quality assurance mechanisms and differences in the substance 
and application of these mechanisms limit the market's transparency and 
raise questions about whether offsets are interchangeable commodities. 
To understand the perspective of consumers, we purchased offsets from 
33 retail providers and found that the information they provided about 
the offsets varied considerably and offered limited assurance of 
credibility. Specifically, 3 of 33 retailers provided information 
related to the additionality of the underlying projects along with our 
purchase, and only 9 provided information related to the use of quality 
assurance mechanisms, including verification and monitoring. A majority 
of the providers, however, did provide further information on their Web 
sites that was not directly related to our transactions. Overall, we 
did not always obtain sufficient information to understand exactly what 
we received as a result of the transaction, and other consumers may 
face similar challenges with their transactions. 

Increased federal oversight of the U.S. voluntary market could address 
some concerns about the credibility of offsets, but would likely 
increase costs for providers and consumers. Similarly, including 
offsets in regulatory programs intended to limit greenhouse gas 
emissions could lower the cost of compliance, but may make it more 
difficult to ensure that the programs achieve their goals. Greater 
oversight of the U.S. voluntary market could increase the credibility 
of offsets and enhance consumer protection, according to certain 
stakeholders and the available literature. However, more oversight 
could reduce flexibility and increase the administrative burden on 
providers, which could raise costs and stifle innovation. Using offsets 
in a mandatory emissions reduction program would involve similar trade- 
offs. Specifically, offsets could lower the cost of compliance, 
encourage investment and innovation in sectors not required to reduce 
emissions, and provide time for regulated entities to change existing 
technologies. Recent EPA analyses state that the cost of compliance 
with proposed greenhouse gas legislation decreases considerably as the 
allowable use of offsets increases. This is because it is often cheaper 
for regulated entities to pay for offsets than to make reductions 
themselves. Several stakeholders said that using offsets for compliance 
could also give regulated entities increased flexibility to meet 
emissions reduction requirements and could give them time to implement 
long-term plans and develop new technologies. However, any use of 
offsets for compliance that lack credibility would undermine the 
achievement of the program's goals. In addition, some stakeholders said 
that the availability of low-cost offsets could discourage regulated 
entities from investing in technology to reduce their own emissions. 
Finally, the stakeholders varied in their views on the extent to which 
regulated entities should be allowed to rely on offsets in a compliance 
scheme. 

We are not recommending executive actions. However, as the Congress 
considers legislation intended to limit greenhouse gas emissions that 
allows the use of carbon offsets for compliance, it may wish to 
incorporate provisions that would direct the relevant federal agency 
(or agencies) to establish (1) clear rules about the types of offset 
projects that regulated entities can use, as well as standardized 
quality assurance mechanisms for these allowable project types; (2) 
procedures to account and compensate for the inherent uncertainty 
associated with offset projects, such as discounting or overall limits 
on the use of offsets for compliance; (3) a standardized registry for 
tracking the creation and ownership of offsets; and (4) procedures for 
amending the offset rules, quality assurance mechanisms, and registry, 
as necessary, based on experience and the availability of new 
information over time. 

The U.S. Voluntary Market Is Growing Rapidly with Limited Federal 
Oversight: 

Over 600 organizations develop, market, or sell offsets in the United 
States, and the market involves a wide range of participants, prices, 
transaction types, and projects. While the exact scope of the U.S. 
voluntary market is uncertain because of a lack of complete data, 
available information shows that the supply of offsets generated in the 
United States has increased by about 66 percent over the last 3 years, 
from about 6.2 million tons in 2004 to about 10.2 million tons in 2007. 
The federal government plays a small role in the U.S. market. While no 
single regulatory body oversees the market, FTC and EPA, among others, 
have undertaken some consumer protection and technical assistance 
efforts. In addition, certain federal entities participate in the 
market as providers and consumers. For example, the Forest Service 
works with a nonprofit partner that solicits donations to support 
forestry projects. 

The Market Includes a Range of Participants, Prices, and Transaction 
Types: 

A wide range of participants are involved in the U.S. voluntary market, 
including providers of different types of offsets, developers of 
quality assurance mechanisms, third party verifiers, and consumers who 
purchase offsets from domestic or international providers. According to 
available data, more than 600 entities are involved in the supply of 
offsets in the United States, including companies, governments, 
colleges and universities, and other organizations. 

* Offset providers include project developers and intermediaries. We 
identified 210 offset providers of various types, including 87 U.S.- 
based providers. Project developers implement individual projects and 
may sell offsets directly to consumers or to intermediaries. 
Intermediaries are further subdivided into retailers, aggregators, and 
brokers, among other categories. Retailers generally sell smaller 
quantities of offsets to individuals or organizations. Aggregators, 
also known as wholesalers, sell in bulk and often own a portfolio of 
offsets. Brokers facilitate transactions between sellers and buyers. 
Providers obtain the rights to the offsets they sell in a number of 
ways, including developing their own projects or purchasing directly 
from project developers, sometimes through brokers. Other providers 
purchase and retire offsets through CCX on behalf of customers. 
Providers may also play multiple roles in the offset market. For 
example, a single company may develop projects, aggregate offsets from 
other projects or providers for resale, and sell offsets directly to 
consumers. In addition, other entities, including investment banks and 
other financial institutions, support the development of projects 
through financing. 

* Quality assurance providers include those involved in activities such 
as verification and monitoring of offset projects, and the development 
of quality assurance mechanisms such as accounting standards for 
calculating offsets. Project developers may use a third party verifier 
to confirm that offsets generated by a project were accurately 
calculated. Once verified, the offset might then be recorded by another 
independent party in a registry to track its sale and ownership. 
Multiple registries operate in the United States to help market 
participants track the ownership and retirement of offsets, although 
not all offsets are listed on registries. 

* A wide variety of consumers buy offsets, including individuals, 
businesses, nonprofits, governments, research institutions, 
universities, religious congregations, utilities, and other 
organizations. Consumers' motivations for purchasing offsets may 
include corporate responsibility and public relations, among others. 
Consumers may purchase offsets to compensate for emissions that result 
from a variety of activities including flying, driving, and purchasing 
consumer products. 

Offsets sell on the market at a wide range of prices. In 2007, prices 
on the global voluntary market ranged from $1.83 per ton to about $306 
per ton, with an average of about $6 per ton, according to one recent 
market study.[Footnote 9] We purchased offsets from 33 retail 
providers, both domestic and international, and prices ranged from 
about $5 per ton to about $31 per ton. CCX prices were at their lowest 
in 2004, at $0.79 per ton, but recently peaked at $7.40 per ton in June 
2008.[Footnote 10] 

There are also different types of carbon offset transactions, including 
direct purchase and payment or donation in support of a service. The 
difference between these transactions is whether the offsets are sold 
as a commodity. In a direct purchase, consumers pay for the delivery of 
offsets as a commoditized economic good. Direct purchases may allow the 
consumer to evaluate the parameters of the offset project, including 
how verification and monitoring methodologies were employed to create 
the offset. When the transaction does not involve the exchange of a 
commodity, consumers pay or donate money to a provider to support the 
retirement of offsets or the development of new offset projects, but 
the consumer does not own an asset after the transaction has been 
completed. In this case, the payment or donation amounts to a promise 
by the provider to supply the service of purchasing offsets or 
supporting offset projects. Donations may be tax deductible, 
effectively reducing the cost of the carbon offset. 

Another key distinction involves the timing of an offset's creation. In 
cases where offsets are sold before they are produced, the quantity of 
offsets generated from projects can be calculated using what is known 
as ex-ante (or future value) accounting. On the other hand, when 
offsets are sold after they are produced, the quantity of offsets can 
be calculated using ex-post accounting. Using future value accounting, 
consumers may purchase an offset today, but it may take several years 
before the offset is generated. 

Project Developers Generate Offsets from a Wide Range of Activities: 

In addition to a range of participants, project developers generate 
offsets from different types of projects by either reducing emissions 
at the source or through sequestration. Emission reduction projects 
involve either fossil fuel projects based on changes in energy 
production and use practices--such as energy efficiency, fuel 
switching, power plant upgrades, and certain renewable energy projects-
-or greenhouse gas destruction projects, including projects that 
capture and destroy methane from coal mines, landfills, and 
agricultural operations. Sequestration projects include biological 
sequestration projects that pull carbon dioxide out of the air by, for 
example, planting trees or enhancing the management of agricultural 
soils, and geological sequestration projects that capture and store 
carbon dioxide in underground formations. See figure 3 for a diagram of 
common types of carbon offset projects, and see appendix II for 
descriptions of offset project types. 

Figure 3: Common Offset Project Types: 

This figure is a flowchart illustrating common offset project types. 

[See PDF for image] 

Source: GAO based on Ricardo Bayon, Amanda Hawn, and Katherine 
Hamilton, Voluntary Carbon Markets, (Sterling, Virgina: Earthscan). 

[End of figure] 

The Scope of the Market Is Uncertain, but Supply Is Growing Rapidly: 

The U.S. voluntary market is part of an expanding global market, with 
an estimated 65 million tons sold in 2007, valued at approximately 
$337.3 million.[Footnote 11] Complete data on the volume of offsets 
traded in the United States are not available, and the market's 
transparency is limited. Efforts to quantify and report on the 
voluntary carbon market have focused on the global market and include 
limited information focused solely on the United States. It is also 
difficult to separate out the U.S. portion of the global market because 
U.S. market participants buy and sell across domestic and international 
boundaries and transactions are private. However, according to one 
study, an estimated 23 percent of the volume sold in 2007 on the global 
market came from U.S. providers.[Footnote 12] 

While the exact scope of the U.S. voluntary carbon offset market is 
uncertain because of a lack of complete data, available information 
shows that the supply of offsets based in the United States is growing 
rapidly. In the last 3 years, the supply of offsets from projects based 
in the United States increased approximately 66 percent, from about 6.2 
million tons in 2004 to about 10.2 million tons in 2007.[Footnote 13] 
By comparison, EPA data show that U.S. greenhouse gas emissions have 
averaged about 7 billion tons annually since 2000. In addition, in 
2007, at least 211 projects produced offsets in the United States, as 
compared to 93 projects in 2004, an increase of about 125 
percent.[Footnote 14] See figure 4 for data on the U.S. supply of 
offsets. 

Figure 4: U.S. Supply of Offsets by Volume and Number of Projects from 
2000 through 2007: 

This figure is a combination line and bar graph showing U.S. supply of 
voluntary offsets by volume and number of projects from 2000 through 
2007. The line represents the volume (metric tons of carbon dioxide 
equivalent) and the bar represents the number of projects. The X axis 
represents the year, and the Y axis represents the number. 

Year: 2000; 
Volume: 1.21995; 
Number of project: 13. 

Year: 2001; 
Volume: 1.23119; 
Number of project: 29. 

Year: 2002; 
Volume: 2.58851; 
Number of project: 48. 

Year: 2003; 
Volume: 5.5488; 
Number of project: 69. 

Year: 2004; 
Volume: 6.16805; 
Number of project: 93. 

Year: 2005; 
Volume: 8.402; 
Number of project: 113. 

Year: 2006; 
Volume: 11.065; 
Number of project: 180. 

Year: 2007; 
Volume: 10.209; 
Number of project: 211. 

[See PDF for image] 

Source: GAO analysis of Point Carbon data. 

[End of figure] 

Of the total U.S. offset supply in 2007, about 85 percent was generated 
from three categories of projects: methane, carbon capture and 
geological storage (CCGS), and biological sequestration. About 49 
percent of U.S. supply was produced from projects that capture and 
destroy methane from coal mines, agricultural operations, or landfills. 
An additional 19 percent was produced from CCGS projects that capture 
emissions from industrial and energy-related emissions sources and then 
store these emissions in geologic formations. Also, 17 percent was 
produced from biological sequestration projects, including agricultural 
soil projects such as no-till farming and forestry projects. Figure 5 
illustrates U.S. offset supply by project type in 2007. 

Figure 5: U.S. Offset Supply by Type of Project in 2007: 

This figure is a combination of three pie charts showing U.S. offset 
supply by type of project in 2007. 

Overall chart: 

Methane projects: 49%; 
CCGS: 19%; 
Biological sequestration: 17%; 
Energy efficiency: 7%; 
Renewable energy: 6%; 
Other: 1%.

Biological sequestration: 

Forestry: 41%; 
Agricultural soil: 37%; 
Rangeland soil: 18%; 
CCBS: 4%. 

Methane projects: 

Coal: 48%; 
Landfill: 36%; 
Agricultural: 16%. 

[See PDF for image] 

Source: GAO analysis of Point Carbon data. 

Notes: CCBS refers to carbon capture and biological storage. Totals may 
not equal 100 because of rounding. 

[End of figure] 

Coal Mine Methane: 

Coal mines account for about 10 percent of all man-made methane 
emissions in the United States. Methane, a potent 
greenhouse gas, is contained in coal seams and presents a safety hazard 
for mine operators because it is explosive at certain concentrations in 
the air. Underground coal mines are designed and operated so that 
methane released during the extraction of coal is removed from the mine 
through powerful ventilation fans and is typically vented to the 
atmosphere. Utilization of recovered methane is not currently a typical 
operational practice at underground coal mines. However, through an 
offset project, such methane could be recovered and 
burned for its energy content or flared to reduce its heat-trapping 
ability when released to the atmosphere.

One factor influencing the quantity of offsets generated from a 
particular project is the type of greenhouse gas involved. This is 
because most greenhouse gases, including methane, have greater heat- 
trapping ability relative to carbon dioxide. Thus, the global warming 
potential of these greenhouse gases influences the volume of offsets 
generated. For example, reducing one ton of methane emissions has the 
same effect as decreasing 25 tons of carbon dioxide.[Footnote 15] 
Accordingly, projects that decrease gases with high global warming 
potential may be attractive from a developer's perspective. 

Available data show that in 2007, 93 of the 211 projects that produced 
offsets in the United States were methane projects.[Footnote 16] Of 
these, 5 coal mine projects--2 percent of the total--accounted for 24 
percent of the total volume generated in 2007. On the other hand, 62 
biological sequestration projects (about 29 percent of the total) 
produced 17 percent of the supply. This includes 52 forestry projects 
that produced about 7 percent of total supply from U.S.-based projects. 
Table 1 presents U.S. project types by number, volume, and percentage 
of total supply in 2007. 

Table 1: U.S. Project Types by Number, Volume, and Percentage of Total 
Supply in 2007: 

Project type: Methane projects; 
Number of projects: 93; 
Percentage of total projects: 44%; 
Total volume: 5,044,583; 
Percentage of total volume: 49%. 

Project type: Agricultural; 
Number of projects: 51; 
Percentage of total projects: 24%; 
Total volume: 798,222; 
Percentage of total volume: 8%. 

Project type: Landfill; 
Number of projects: 37; 
Percentage of total projects: 18%; 
Total volume: 1,803,111; 
Percentage of total volume: 18%. 

Project type: Coal; 
Number of projects: 5; 
Percentage of total projects: 2%; 
Total volume: 2,443,250; 
Percentage of total volume: 24%. 

Project type: Biological sequestration; 
Number of projects: 62; 
Percentage of total projects: 29%; 
Total volume: 1,706,982; 
Percentage of total volume: 17%. 

Project type: Forestry; 
Number of projects: 52; 
Percentage of total projects: 25%; 
Total volume: 693,282; 
Percentage of total volume: 7%. 

Project type: Agricultural soil; 
Number of projects: 7; 
Percentage of total projects: 3%; 
Total volume: 628,700; 
Percentage of total volume: 6%. 

Project type: Rangeland soil; 
Number of projects: 2; 
Percentage of total projects: 1%; 
Total volume: 310,000; 
Percentage of total volume: 3%. 

Project type: Carbon capture and biological storage (CCBS); 
Number of projects: 1; 
Percentage of total projects: <1%; 
Total volume: 75,000; 
Percentage of total volume: 1%. 

Project type: Renewable energy; 
Number of projects: 33; 
Percentage of total projects: 16%; 
Total volume: 631,073; 
Percentage of total volume: 6%. 

Project type: Energy efficiency; 
Number of projects: 10; 
Percentage of total projects: 5%; 
Total volume: 701,262; 
Percentage of total volume: 7%. 

Project type: Carbon capture and geological storage; 
Number of projects: 7; 
Percentage of total projects: 3%; 
Total volume: 1,977,366; 
Percentage of total volume: 19%. 

Project type: Other; 
Number of projects: 6; 
Percentage of total projects: 3%; 
Total volume: 147,770; 
Percentage of total volume: 1%. 

Project type: Total; 
Number of projects: 211; 
Percentage of total projects: [Empty]; 
Total volume: 10,209,036; 
Percentage of total volume: [Empty]. 

Source: GAO analysis of Point Carbon data. 

Note: Totals may not equal 100 because of rounding. 

[End of table] 

In the United States, projects are located in 40 states, but 34 percent 
of the supply in 2007 was produced by 14 projects in Texas and 
Virginia. Projects in these states include high-yielding projects such 
as coal mine methane projects. While California had the greatest number 
of projects in 2007, these 31 projects accounted for about 4 percent of 
the total supply. Figure 6 presents the volume and number of offset 
projects by state, and detailed data are provided in appendix III. 

Figure 6: Volume and Number of Offset Projects by State in 2007: 

This figure is a map of the United States showing the volume and number 
of offset projects by state in 2007. 

[See PDF for image] 

Source: GAO analysis of Point Carbon data; Map Resources (map). 

Note: Twelve projects occur across multiple states. The data for these 
projects are included under the category of multiple states and not 
included in the volume or number of projects for the individual states 
involved in these projects. 

[End of figure] 

The Federal Government Plays a Small Role in the Market: 

While no single regulatory body has oversight of the U.S. voluntary 
carbon offset market as a whole, offset transactions are subject to 
applicable state fraud and consumer protection laws, which are 
generally enforced by each state's attorney general. Certain federal 
entities provide some consumer protection and technical assistance 
efforts and also participate in the market as providers and consumers. 

* Commodity Futures Trading Commission: 

The mission of the Commodity Futures Trading Commission is to protect 
market users and the public from fraud, manipulation, and abusive 
practices related to the sale of commodity and financial futures and 
options, and to foster open, competitive, and financially sound futures 
and option markets. The CFTC exercises limited oversight over the 
Chicago Climate Exchange due to its status as an Exempt Commercial 
Market (ECM), a category established under the Commodity Futures 
Modernization Act of 2000. Participants in such markets, in general 
terms, must be large, sophisticated traders. Moreover, ECMs are allowed 
to trade only exempt commodities.[Footnote 17] ECMs must abide by 
certain notification requirements and affirm annually that they 
continue to operate under the same parameters. 

The 2008 Farm Bill increases the CFTC's oversight of ECM contracts that 
serve a significant price discovery function.[Footnote 18] The CFTC 
confirmed that CCX is eligible to operate as an ECM, but at this time, 
CCX's contracts have not been determined by the CFTC to serve a 
significant price discovery function. In cases where contracts serve a 
significant price discovery function, ECMs must adhere to a number of 
core principles, including monitoring of trading and the submission of 
certain data to the CFTC. Generally, CCX operates with less oversight 
because participants in the market are experienced. However, if the 
CFTC receives complaints, it can take appropriate action. 

* Department of Agriculture, Forest Service: 

The mission of the Forest Service, an agency within the Department of 
Agriculture (USDA), is to sustain the health, diversity, and 
productivity of the nation's forests and grasslands to meet the needs 
of present and future generations. The Forest Service works with a 
congressionally chartered nonprofit partner, the National Forest 
Foundation (NFF), to solicit donations to the Carbon Capital Fund, 
which provides financial support for carbon sequestration projects on 
lands managed by the Forest Service. The Carbon Capital Fund donations 
are invested in Forest Service reforestation projects to sequester 
carbon. According to the Forest Service, donations to the Carbon 
Capital Fund will be used to replant areas on national forests that 
have been damaged by wildfire and other natural disturbances and to 
demonstrate the role of forest carbon sequestration in addressing 
climate change. The Forest Service manages the reforestation projects 
and also selects the project sites by using a forest vegetation 
simulation model to estimate the amount of carbon that will be 
sequestered by prospective projects. NFF operates the fund and uses a 
private contractor to measure and verify offsets. The first 
demonstration project was planned for the summer of 2008 on the Custer 
National Forest in Montana and South Dakota, and projects tentatively 
scheduled for the summer of 2009 will take place on the Plumas and San 
Bernardino National Forests in California. 

According to Forest Service and NFF officials, they offer no guarantees 
about the performance of Carbon Capital Fund projects. Donations to the 
fund do not transfer rights or ownership of offsets. USDA officials 
said that contributions to the fund are donations and do not create 
tradable offsets. These officials also said that donations to the 
Carbon Capital Fund would enable the Forest Service to plant trees, 
which would, in the long term, lead to carbon reductions. NFF said that 
it would notify donors if the forestry projects fail and that it plans 
to send documentation to donors, including pictures, when projects are 
complete. As of January 2008, a total of about $55,000 had been donated 
to the fund. Ten percent of the donations was set aside for third party 
verification and monitoring, according to NFF. 

USDA also encourages the use of consistent forestry and agriculture 
offset methodologies by working with market participants such as the 
Chicago Climate Exchange and state and regional programs. For example, 
USDA's Natural Resources Conservation Service provided a $750,000 grant 
to the Chicago Climate Exchange to promote the inclusion of agriculture 
projects in the offset market by lowering costs and developing 
methodologies for calculating reductions from no-till farming and 
establishing a pool of project verifiers. 

* Department of Energy, Energy Information Administration: 

The mission of the Energy Information Administration (EIA) is to 
provide policy-neutral data, forecasts, and analyses to promote sound 
policy making, efficient markets, and public understanding regarding 
energy and its interaction with the economy and the environment. EIA's 
Voluntary Reporting of Greenhouse Gases Program, established under 
section 1605(b) of the Energy Policy Act of 1992, provides a means for 
organizations and individuals who have reduced their emissions to 
record their accomplishments in a registry. In 2006 and 2007, EIA 
revised the program to allow participants to report on offsets in 
certain circumstances. The revised guidelines have not yet been 
implemented. 

* Department of the Interior, U.S. Fish and Wildlife Service: 

The mission of the U.S. Fish and Wildlife Service (FWS), a bureau 
within the Department of the Interior, is to conserve, protect, and 
enhance fish, wildlife, and plants and their habitats for the 
continuing benefit of the American people. FWS partners with companies 
and nonprofits to develop carbon sequestration projects on national 
wildlife refuges in the southeastern United States. FWS enters into 
these partnerships to obtain funds to restore and enhance native forest 
and wildlife habitat on national wildlife refuges. FWS identifies 
refuge lands that are important for its overall conservation goals and 
manages sequestration projects on these lands, but does not play a role 
in the calculation, verification, or monitoring of carbon offsets. 
Carbon sequestration projects must support the purposes of each 
national wildlife refuge and be consistent with refuge forest 
management plans. FWS negotiates additional funding commitments with 
partners to meet long-term operations and maintenance needs as well. 

In return for funding carbon sequestration activities related to FWS 
conservation goals, partners retain rights to any carbon credits that 
may result from the restoration projects. The partners may in turn 
provide their clients or donors with the opportunity to offset their 
carbon emissions by contributing funds to these projects. Companies 
involved in partnership agreements with FWS may restore or reforest 
refuges, or buy land identified by FWS and then gift the land back to 
FWS and underwrite the restoration of that land. Partners include 
energy companies and nonprofit land trusts. According to FWS, these 
partnerships have led to the addition of 40,000 acres of land to the 
refuge system and restored a total of 80,000 acres of wildlife habitat 
with more than 22 million trees. The Solicitor's Office of the 
Department of the Interior determined that FWS may accept donations of 
this kind as long as it complies with the Department of the Interior's 
guidelines for accepting donations and applicable laws and regulations. 

* Environmental Protection Agency: 

The mission of the Environmental Protection Agency is to protect human 
health and the environment. EPA Climate Leaders, a voluntary emissions 
reduction program, provides technical assistance to companies on 
calculating and tracking greenhouse gas emissions over time, 
calculating emissions reductions from offsets, and incorporating 
offsets into emission reduction strategies. In the Climate Leaders 
program, partner companies commit to reduce their impact on the 
environment by completing a greenhouse gas emissions inventory, setting 
reduction goals, and annually reporting progress to EPA. EPA also 
provides guidance to partners on calculating emissions reductions from 
offsets. For offsets to be credible, according to EPA, they must meet 
four key accounting principles: the offsets must be real, additional, 
permanent, and verifiable. Partners may choose to develop their own 
offset projects or purchase offsets. Offset projects must meet Climate 
Leaders requirements for use toward meeting a greenhouse gas reduction 
goal, including the use of a performance standard-based approach to 
quantifying emissions reductions. EPA has developed accounting 
methodologies for certain offset project types, including landfill gas, 
manure management, afforestation, transportation, and boiler 
replacement projects. EPA is also developing protocols for additional 
project types, such as coal bed methane. 

* Federal Trade Commission: 

The mission of the Federal Trade Commission is to protect consumers, 
strengthen free and open markets, and promote informed consumer choice. 
The Federal Trade Commission Act prohibits unfair or deceptive trade 
practices, including deceptive advertising. Among other things, the FTC 
enforces a wide variety of consumer protection laws and is evaluating 
the treatment of carbon offsets in its Green Guides, a publication 
designed to help advertisers avoid making false or misleading 
environmental marketing claims.[Footnote 19] The FTC announced in 
November 2007 that it would conduct a regulatory review of the Green 
Guides, which were last updated in 1998 and do not currently address 
carbon offsets. According to the FTC, carbon offset marketing claims 
may present a heightened potential for deception because it is 
difficult, if not impossible, for consumers to verify the accuracy of 
the seller's claims. The FTC held a public workshop in January 2008 
about carbon offsets to obtain input on consumer protection issues and 
to determine whether more direct guidance is needed. The workshop 
examined the emerging market for greenhouse gas emission reduction 
products and related advertising claims, among other issues. The FTC is 
reviewing the public comments obtained through the workshop but has not 
issued proposed changes to the guides and has not decided whether to 
issue guidance specifically regarding offsets. 

* U.S. House of Representatives, Office of the Chief Administrative 
Officer: 

The Office of the Chief Administrative Officer provides operations 
infrastructure and support services for the community of about 10,000 
House Members, officers, and staff. The CAO purchased 30,000 metric 
tons of offsets through the Chicago Climate Exchange as part of the 
Green the Capitol Initiative, an effort to reduce the greenhouse gas 
emissions from House operations. Among other measures, the Green the 
Capitol Initiative outlines three strategies, including (1) purchasing 
electricity generated from renewable sources; (2) meeting the House's 
heating and cooling needs by switching from using coal, oil, and 
natural gas at the Capitol power plant to natural gas only; and (3) 
purchasing offsets to compensate for any remaining carbon emissions. 
See appendix IV for more information about the purchase of offsets by 
the CAO. 

A Variety of Quality Assurance Mechanisms Are Available and Used, but 
Information on the Credibility of Offsets Is Limited: 

Multiple quality assurance mechanisms are available and used to ensure 
the credibility of carbon offsets available for purchase on the U.S. 
voluntary offset market, but a lack of centralized information makes it 
difficult to estimate the extent of their use. Participants in the 
offset market face several challenges to ensuring the credibility of 
offsets, including problems determining additionality, and the 
availability and use of many mechanisms for verification, and 
monitoring. Our purchase of offsets found that the information supplied 
by a nonprobability sample of retailers provides limited assurance of 
credibility. 

Quality Assurance Mechanisms Are Available and Applied to Offset 
Projects, but the Extent of Their Use Is Uncertain: 

A wide range of quality assurance mechanisms, commonly described 
collectively as "standards," are available to ensure the credibility of 
carbon offsets. Market participants and third parties apply these 
standards at different stages of the carbon offset supply chain for a 
variety of purposes. For example, accounting and reporting methods 
define how to measure emissions reductions from specific types of 
projects. In addition, verification and monitoring standards are used 
to confirm that offsets are calculated correctly and that a project was 
indeed implemented, and to monitor progress over time. End use product 
standards, applied later in the supply chain, can be used to certify 
product marketing claims. Certain mechanisms cover multiple aspects of 
quality assurance and specify the use of registries to track the 
ownership and disposition of offsets, while others focus on one aspect, 
such as ensuring that emissions reductions are calculated correctly. 
Figure 7 illustrates how quality assurance mechanisms relate to the 
various components of a simplified offset supply chain, and appendix 
VII describes selected offset standards used in the voluntary market. 

Figure 7: Quality Assurance Mechanisms in a Simplified Carbon Offset 
Supply Chain: 

This figure is a chart showing quality assurance mechanisms in a 
simplified carbon offset supply chain. 

[See PDF for image] 

Source: GAO based on Ricardo Bayon, Amanda Hawn, and Katherine 
Hamilton, Voluntary Carbon Markets. 

[End of figure] 

Our review of the available literature and discussions with 
stakeholders identified widely varying estimates of the extent to which 
market participants use quality assurance mechanisms. Available 
information suggests that many carbon offsets in the voluntary market 
were subject to a quality assurance mechanism, but the fragmented 
nature of the market and limited data preclude exact estimates of the 
use of such mechanisms. One study estimated that more than 85 percent 
of the offsets purchased on the retail market in 2007 were verified by 
third parties, but this estimate did not include data on verification 
for many transactions.[Footnote 20] In contrast, another study stated 
that the majority of voluntary offsets are currently not certified 
against a third party standard.[Footnote 21] The available information 
suggests that fewer providers use registries to track the ownership and 
disposition of offsets than use third party verification or other 
quality assurance mechanisms. For example, one study estimated that 
more than 50 percent of the offsets available on the retail market were 
not listed in a registry, but this estimate did not include data for 
many transactions.[Footnote 22] Because of incomplete and conflicting 
data on the use of quality assurance mechanisms, including registries, 
we cannot accurately gauge the extent of their use. In addition, these 
data limitations detract from the market's transparency. 

Market Participants Face Challenges in Ensuring the Credibility of 
Offsets: 

Our interviews with stakeholders identified additionality and the 
presence of many different verification and monitoring methods as the 
two greatest challenges facing participants in the market. This is 
important because stakeholders and the available literature identify 
additionality and verification and monitoring as among the most 
important characteristics for establishing the credibility of 
offsets.[Footnote 23] (See app. V for more information about 
stakeholders' ratings of characteristics of offset credibility and 
market challenges.) 

According to most stakeholders and key studies, additionality is 
fundamental to the credibility of offsets because only offsets that are 
additional to business-as-usual activities result in new environmental 
benefits. However, certain stakeholders said that additionality is not 
a critical factor at this early stage in the development of carbon 
markets and that the key goal should be to keep transaction costs and 
barriers to entry low to create financial incentives for reducing 
emissions. Several stakeholders said that there is no correct technique 
for determining additionality because it requires comparison of 
expected reductions against a projected business-as-usual emissions 
baseline (also referred to as a counterfactual scenario). Determining 
additionality is inherently uncertain because, it may not be possible 
to know what would have happened in the future had the projects not 
been undertaken. 

Stakeholders offered different definitions for additionality and 
preferred different methods for determining whether projects are 
additional. For example, some stakeholders said that additionality 
should be evaluated on a case-by-case examination of the unique 
circumstances of each project, while other stakeholders preferred 
evaluating projects against efficiency standards for a technology or 
sector, known as a performance benchmark approach. There are many other 
ways to determine whether projects are additional, and many 
stakeholders said that applying a single test is too simplistic because 
every project is different from others and operates under different 
circumstances. See table 2 for descriptions of selected additionality 
tests. 

Table 2: Descriptions of Selected Additionality Tests: 

Additionality test: Barriers; 
General description: The underlying assumption of this test is that the 
production of offsets is a decisive reason that a project is able to 
overcome significant implementation barriers, such as local resistance 
to new technologies. Under other versions of the test, at least one 
alternative of the project must be shown not to face such barriers. 

Additionality test: Common practice; 
General description: To meet this test, an offset project must reduce 
emissions below levels produced by "common practice" technologies that 
provide the same products and services as the project. If the project 
does not meet the test, the assumption is that offsets are not a 
decisive reason for pursuing the project. 

Additionality test: Investment, or financial; 
General description: The most common version of this test (often termed 
financial additionality) assumes an offset project to be additional if 
it can be demonstrated that the project would have a lower than 
acceptable rate of return without revenue from offsets. The underlying 
assumption is that offsets must be a decisive reason for implementing a 
project that is not an attractive investment without revenues 
associated with those offsets. Under some versions of this test, an 
offset project with a high or competitive rate of return could still be 
additional, but must demonstrate additionality through other means. 

Additionality test: Legal, regulatory, or institutional; 
General description: To satisfy this test, an offset project must 
reduce emissions below the level required by any official policies, 
regulations, guidance, or industry standards. If it does not reduce 
emissions beyond these levels, the assumption is that the only real 
reason for pursuing the project is compliance and the project, 
therefore, is not additional. Under some versions of this test, the 
converse is true-if the project reduces emissions beyond required 
levels, it is assumed that the only reason for pursuing the project is 
to earn offsets, and the project is therefore additional. 

Additionality test: Performance benchmark; 
General description: To meet this test, an offset project must 
demonstrate an emissions rate that is lower than a predetermined 
benchmark emissions rate for a particular technology or practice. This 
test is premised on the assumption that most, if not all, projects that 
beat the specified benchmark are ones in which climate change 
mitigation is a decisive factor in the decision to exceed the 
benchmark. The benchmark may also be used to calculate baseline 
emissions. 

Additionality test: Project in, project out; 
General description: This test reviews whether an offset project 
results in lower emissions than a scenario in which the project had not 
been implemented. If emissions associated with the project are lower 
than the business-as-usual scenario, then it is assumed that reducing 
emissions was a decisive reason for the project and that the project is 
additional. 

Additionality test: Technology; 
General description: The offset project and its associated reductions 
are considered additional if the offset project involves a technology 
specified as not being business as usual. The default assumption is 
that for these "additional" technologies, offsets are a decisive reason 
for using the technology in a particular project. 

Additionality test: Timing; 
General description: In this test, an offset project must have been 
initiated after a certain date, such as the date of initiation of a 
compliance program. The assumption is that any project started before 
that date must have had motivations other than offsets. Under most 
versions of this test, projects started after the required date must 
also establish additionality through a second test. 

Source: GAO analysis of Dr. Mark C. Trexler, Derik J. Broekhoff, and 
Laura H. Kosloff. "A Statistically-Driven Approach to Offset-Based GHG 
Additionality Determinations: What Can We Learn?" Sustainable 
Development Law and Policy, Vol. VI, Iss. 2 (Winter 2006): 30-40. 

Note: This table summarizes and introduces the variety of additionality 
tests that have been circulated over the past decade. It is not an 
exhaustive list of additionality tests, nor is it intended to provide 
precise definitions of the different tests. 

[End of table] 

Stakeholders also identified the existence of many different 
verification and monitoring methods as a key challenge to ensuring the 
credibility of offsets. There are many standards for measuring, 
verifying, monitoring, and tracking the distribution of carbon offsets 
but few standards, if any, that cover the entire supply chain. The 
proliferation of standards has caused confusion in the market, and the 
existence of multiple quality assurance mechanisms with different 
requirements raises questions about the quality of offsets available on 
the voluntary market, according to many stakeholders. 

The lack of standardization in the U.S. market may also make it 
difficult for consumers to determine whether offsets are fully 
fungible--interchangeable and of comparable quality--a characteristic 
of an efficient commodity market. The term "carbon offset" implies a 
uniform commodity, but offsets may originate from a wide variety of 
project types based on different quantification and quality assurance 
mechanisms. Because offsets are not all the same, it may be difficult 
for consumers to understand what they purchase. In addition, several 
stakeholders said that a standardized offset registration process would 
foster transparency and prevent double-counting. Because there is no 
single registry and because of a lack of communication among existing 
registries, it is difficult for consumers to determine the quality of 
the offsets they purchase. 

Certain stakeholders said that a single standard would bring greater 
credibility to the voluntary carbon offset market and result in 
projects that meet more stringent protocols. However, some stakeholders 
said that they did not expect that a single standard would emerge 
because of the wide variety and complexity of offset projects. Further, 
several stakeholders said that a single standard may not be desirable 
because it could stifle innovation and limit access to the market. 
Certain stakeholders said that the flexibility offered by multiple 
standards encourages the testing of new methodologies and emissions 
reduction technologies. 

While the concept of carbon offsets rests on the notion that a ton of 
carbon reduced, avoided, or sequestered is the same regardless of the 
activity that generated the offset, some stakeholders believe that 
certain types of projects are more credible than others. Specifically, 
the stakeholders identified methane capture and fuel-switching projects 
as the most credible, and renewable energy certificates (REC) and 
agricultural and rangeland soil carbon sequestration as less 
credible.[Footnote 24] Some stakeholders also pointed out that projects 
that use future value accounting practices to calculate offsets may be 
less credible. However, certain stakeholders said that this does not 
mean such projects should be categorically excluded from the offset 
market, only that they may require more rigorous quality assurance. 
Approximately one-third of the respondents said that credibility varies 
depending upon circumstances specific to the project. See table 5 in 
appendix V for more details about stakeholders' rating of the 
credibility of different types of carbon offset projects. 

The stakeholders' views on the credibility of different project types 
may stem from the fact that methane and fuel-switching projects are 
relatively simple to measure and verify, while RECs, forestry, and 
agricultural and rangeland soil carbon projects face challenges related 
to additionality, measurement, and permanence. According to several 
stakeholders, RECs and carbon offsets are not comparable environmental 
commodities and differ in their objectives, the actions they represent, 
and the standards by which they are defined. RECs certify that a 
certain quantity of electricity has been generated from a qualifying 
type of renewable generation technology, whereas carbon offsets 
represent an amount of carbon reduced in comparison with a projected 
business-as-usual emissions baseline. RECs may be bought and sold to 
satisfy state-level requirements to produce electricity from renewable 
sources--known as renewable portfolio standards--and also in the 
voluntary carbon offset market. The carbon benefits of RECs may be 
double-counted if sold in both markets, according to some stakeholders. 
With respect to agricultural and rangeland sequestration and forestry, 
certain stakeholders said it is difficult to accurately measure 
emissions reductions from these types of projects. In addition, 
forestry offset projects may not be permanent because disturbances such 
as insect outbreaks and fire can return stored carbon to the 
atmosphere. 

Projects using future value accounting practices to calculate offsets 
may also be less credible than those that do not, according to some 
stakeholders. Ensuring the credibility of offsets purchased before they 
are produced inherently involves a higher degree of uncertainty than 
purchasing an offset that has already been generated. Some stakeholders 
told us that future value accounting practices expose consumers to more 
risk that the offsets will not materialize because it is more difficult 
to verify and monitor such projects over time. Other stakeholders said 
that future value accounting is an important way to fund certain types 
of offset projects that might otherwise not be possible. 

Information Provided to Consumers Offers Limited Assurance of 
Credibility: 

The information provided to consumers about offset projects and quality 
assurance mechanisms offers limited assurance of credibility, according 
to certain stakeholders and analysis of documents obtained through the 
purchase of offsets. Several studies and stakeholders said that it is 
difficult for consumers to make educated choices about offset purchases 
because the information they need may not be provided by retail offset 
providers. However, one stakeholder said that the strengths and 
weaknesses of offsets could be determined with a reasonable amount of 
due diligence, which is important to any buyer of a commodity in an 
emerging market. 

To better understand the perspective of consumers, we purchased offsets 
from 33 retail providers and found that the information provided about 
the offsets varied considerably and offered limited assurance of 
credibility. We retrospectively analyzed information provided to us by 
the retailers directly as a result of the transaction as well as 
information provided on their Web sites. We expected that the 
information provided by retailers as a result of the transaction would 
yield detailed project-specific information related to credibility, and 
our review of Web sites was intended to supplement the information 
received directly from providers as a result of transactions. We found 
that retailers provided limited information about important 
characteristics for establishing the credibility of offsets, including 
additionality, verification, and the use of a registry to track 
offsets. We also found that few retailers identified specific projects 
associated with our transactions, and that the information provided on 
Web sites--in some cases general information about the retailers' 
quality assurance approaches--could not be linked to particular 
transactions. As a result, we found it difficult, in many cases, to 
determine exactly what we had purchased, and consumers in the offset 
market may face similar challenges. 

With respect to information provided directly as a result of a 
transaction, 3 of 33 retailers said that their offsets were additional 
but only 2 explained how they defined additionality. The remaining 30 
retailers did not provide information on additionality. With regard to 
verification, less than one-third of retailers (9 of 33) specified that 
their offsets were verified by a third party. The remaining 24 
retailers did not provide information on verification. In addition, 5 
of 33 retailers specified that the offsets were tracked in a registry 
and included the name of the registry, and 4 of these provided 
associated tracking numbers. The remaining 28 retailers did not provide 
information about the use of a registry. Further, as a direct result of 
the transaction, less than half of the retailers (13 of 33) provided 
information about whether the transaction resulted in the exchange of a 
good or the provision of a service. 

We also found that retailers provided limited information about the 
offset projects associated with our transactions. Less than half (13 of 
33) provided information about the location of their projects, but the 
majority of retailers (24 of 33) provided information on the type of 
project, and 9 of these retailers identified multiple project types. In 
addition, 8 retailers provided information related to the timing of the 
project, specifically, when the project started or is scheduled to 
begin or when the offsets would occur. 

However, many provided more information on their Web sites that was not 
directly related to our transactions. We found that almost all of the 
retailers (30 of 33) provided some information related to verification 
on their Web sites. This information varied considerably among the 
retailers, with all 30 stating that the offsets were verified and 6 
providing detailed information such as verification reports. With 
regard to additionality, 22 retailers provided information on their Web 
sites, including some explanation of how they define additionality. 
Finally, less than half of the retailers (12 of 33) said that their 
offsets are tracked in a registry, including 10 retailers that 
identified a specific registry, and 2 that operate their own. 

Both Increased Federal Oversight and the Use of Offsets in Climate 
Change Policies Involve Trade-offs between Cost and Credibility: 

Increased government oversight of the voluntary market could address 
some concerns about the credibility of offsets by standardizing quality 
assurance mechanisms and registries, and this could encourage new 
projects and help protect consumers. However, more oversight could 
reduce flexibility and increase the administrative burden for 
government agencies and providers, which could raise costs and stifle 
innovation. Using offsets in a mandatory emissions reduction program 
would involve similar trade-offs. Offsets could lower the cost of 
compliance, encourage investment and innovation in sectors not required 
to reduce emissions, and provide time for regulated entities to change 
existing technologies. However, if the offsets used for compliance are 
not credible, the environmental integrity of a compliance system may be 
compromised. 

More Oversight of the Voluntary Market Involves Trade-offs between 
Credibility and Cost: 

Increased oversight could address some concerns about the credibility 
of offsets by standardizing the use of quality assurance mechanisms and 
registries. Some stakeholders said that the voluntary offset market 
cannot operate efficiently without standardized mechanisms for ensuring 
the credibility of offsets. More government oversight could also help 
increase the fungibility and commoditization of offsets and improve the 
market's transparency. Other benefits of oversight and standardization 
could include encouraging the development of new projects, improving 
consumer protection and awareness, and addressing concerns about 
weaknesses of the voluntary market spilling over into a future 
compliance market. Certain stakeholders said that enhanced oversight of 
the voluntary carbon market would provide it with increased legitimacy 
that would help to spur new offset projects and increase the size of 
the market. 

On the other hand, increased oversight would likely increase the cost 
of providing offsets in the voluntary market by introducing complex 
quality assurance requirements, which reduce flexibility and increase 
transaction costs. Oversight could also stifle innovation, according to 
some stakeholders, by requiring complex procedures with greater 
administrative costs, and by excluding some types of offset projects 
from the market. The federal government could also incur costs 
associated with increased oversight activities. 

Stakeholders held different opinions about whether the government 
should play a larger role in the U.S. voluntary market. Several said 
that organizations have already invested time, money, and expertise in 
developing standards and that increased oversight should rely on and 
build on these investments. Other stakeholders thought that 
standardized quality assurance methods and registries would evolve 
naturally over time as the result of market forces. Several 
stakeholders said that government should focus on creating a mandatory 
greenhouse gas reduction program instead of improving the voluntary 
market and that a future compliance market will largely drive the 
standards for the voluntary market. 

Certain stakeholders and available studies illustrated several policy 
options for enhancing oversight of the market. One option would involve 
requiring participants in the market to adopt standardized quality 
assurance mechanisms and use a specific registry. A second option would 
involve the federal government providing incentives or developing 
voluntary programs to encourage participants to take certain actions. 
Other options include prohibiting certain types of projects that are 
considered less credible and applying discounts or imposing insurance 
requirements on certain types of offsets with greater uncertainty or 
potential for failure. As an example of government oversight in the 
voluntary offset market, several stakeholders mentioned the United 
Kingdom Department for Environment, Food and Rural Affairs (DEFRA) 
framework for the Code of Best Practice for Carbon Offsetting. The code 
is designed to increase consumer confidence in the integrity of carbon 
offsets available for purchase in the United Kingdom. Offset products 
meeting the requirements of the code will be assigned a certification 
mark that providers may use for marketing purposes. The code initially 
covers only Certified Emissions Reductions that are compliant with the 
Kyoto Protocol, but voluntary emissions reductions could be included in 
the code in the future. 

Offsets Could Lower the Cost of Future Mitigation Policies but Increase 
Uncertainty about Achieving Emissions Reductions: 

Allowing offsets in a future compliance scheme could decrease the 
overall compliance costs because it could provide regulated entities 
with a wider variety of compliance options. In many cases, regulated 
entities may find it economically advantageous to buy offsets instead 
of reducing emissions themselves. Recent EPA analyses state that the 
cost of compliance with mitigation policies under consideration by the 
Congress decreases substantially as the use of offsets increases. 
Specifically, the agency's recent analysis of the Climate Security Act 
of 2008 (S. 2191) reported that if the use of domestic and 
international offsets is unlimited, then compliance costs fall by an 
estimated 71 percent compared to the bill as written.[Footnote 25] 
Alternatively, the price increases by an estimated 93 percent compared 
to the bill as written if no offsets are allowed. A 2007 EPA study 
analyzing the economic impacts of the Climate Stewardship and 
Innovation Act of 2007 (S. 280) found similar results.[Footnote 26] 
Other quantitative studies by economists also show that the use of 
offsets will decrease the cost of achieving emissions 
reductions.[Footnote 27] In general, the carbon price is lower in 
quantitative models of a U.S. compliance system when domestic and 
international offsets are widely available and their use is 
unrestricted.[Footnote 28] Using offsets in a compliance scheme could 
also increase the administrative costs of the scheme because of 
increased government oversight of quality assurance mechanisms used to 
ensure the credibility of offsets. 

A lower carbon price due to the availability of offsets as a compliance 
tool may have several effects, according to available economic 
literature. In the short term, lower prices make compliance with a 
policy to reduce emissions less expensive. Lower prices may also 
facilitate agreements to limit emissions and enhance their 
environmental integrity by reducing the incentive for regulated sources 
to either cheat on the agreement or shift production to areas where 
carbon emissions are not regulated.[Footnote 29] Including offsets in 
compliance schemes could also encourage investment and innovation in 
unregulated sectors of the economy, possibly at the expense of 
investment and innovation in regulated sectors.[Footnote 30] According 
to several stakeholders and available economic literature, a market for 
offsets may support climate-related innovation in sectors that supply 
offsets. For example, unregulated facilities may devise new ways to 
limit greenhouse gas emissions because they could sell offsets in the 
compliance market. 

The availability of offsets in a compliance scheme could also provide 
time for regulated facilities to develop new technologies and 
processes. Some stakeholders said that access to offsets provides more 
flexibility in meeting short-term requirements, leaving more time to 
implement long-term plans for internal emissions reductions and 
technology development. Further, according to certain stakeholders, 
offsets may allow regulated sources to continue using assets such as 
power plants until the end of their useful lives, thereby reducing 
their premature retirement and the cost of emissions reductions 
overall. In addition, multiple stakeholders said that offsets may allow 
covered sources to avoid investing in long-lived assets that achieve 
only marginal improvements, instead focusing on more effective assets 
that take longer to develop. 

On the other hand, allowing the use of offsets could compromise the 
environmental integrity of a compliance system if nonadditional offsets 
are used as compliance tools. Certain stakeholders said that because 
offset programs increase the total quantity of compliance instruments 
available to regulated sources, the integrity of the system can be 
maintained only if offsets are additional. If a significant number of 
nonadditional offsets enter the market, emissions may rise beyond 
levels intended by the scheme, according to some stakeholders. 
Nonadditional offsets could thus increase uncertainty about achieving 
emissions reduction goals. This concern underscores the importance of 
using quality assurance mechanisms to ensure the credibility of any 
offsets allowed into a compliance scheme. In addition, these concerns 
could be minimized by limiting the use of offsets or including policy 
options for enhancing oversight of the market such as applying 
discounts or imposing insurance requirements on offsets with greater 
uncertainty or potential for failure. 

The available economic literature supports some of the environmental 
integrity concerns raised by stakeholders. Economic analyses of offsets 
acknowledge difficulties with their use, including baseline 
determination, additionality, permanence, double-counting, and 
verification and monitoring.[Footnote 31] If these criteria are more 
likely to be satisfied by internal reductions from regulated sources 
than by offsets, the use of offsets may result in greater emissions, 
according to these sources. Economists have also identified "leakage" 
as a potential problem for offsets, especially those created on a 
project-by-project basis. Leakage occurs when economic activity is 
shifted as a result of emission control regulation. Consequently, 
emissions abatement achieved in one location that is subject to 
emission control regulation is diminished by increased emissions in 
unregulated locations. For an offset project, leakage occurs when 
economic activity is shifted from the site of the offset project to 
another location or sector where emissions are not controlled. For 
example, an offset project that restricts timber harvesting at a 
specific site may boost logging at an alternative location, thus 
reducing the effectiveness of the offset project. Forestry projects are 
thought to be particularly vulnerable to these challenges, as are 
credits originating in developing countries, even though these offsets 
have been identified as sources of significant cost savings to 
compliance regimes in developed countries.[Footnote 32] 

Multiple stakeholders also said that including offsets in a compliance 
scheme could slow investment in certain emissions reduction 
technologies in regulated sectors and lessen the motivation of market 
participants to reduce their own emissions. According to some 
stakeholders, if more cost-effective offsets are available as 
compliance tools, regulated sources may delay making investments to 
reduce emissions internally, an outcome that could ultimately slow the 
development of, and transition to, a less carbon-intensive economy. For 
example, a senior representative of the Council on Environmental 
Quality said that there is a trade-off between short-term focus on the 
marginal cost of reductions and long-term investment in technology. 
This representative said that offsets may be a cheaper way to reduce 
emissions today, but that investment in technology, not offsets, builds 
emissions reductions into the economy for the long term. Other 
stakeholders and the available economic literature raise similar 
concerns. According to the literature, a market for offsets may support 
innovation in sectors that supply offsets at the expense of investment 
in technology to reduce emissions from regulated sources. Furthermore, 
certain stakeholders said that it may be more difficult for regulators 
to mandate the amount and timing of emissions reductions in specific 
economic sectors if offsets are part of a compliance scheme. 

Certain stakeholders suggested imposing limits on the use of offsets in 
a compliance scheme to address some of these challenges, but 
stakeholders held different opinions about the potential effectiveness 
of this approach. Some said it may be necessary to place restrictions 
on the use of offsets in order to achieve internal emissions reductions 
from regulated sources. If all the effort to reduce emissions is in the 
form of offsets, then the compliance system may not provide the price 
signals necessary for long-term investment in technology at domestic 
industrial facilities and power plants, according to multiple 
stakeholders. They said that domestic abatement is central to achieving 
the long-term goal of any emissions reduction system. However, other 
stakeholders said that incorporating offsets into a compliance scheme 
will enable greater overall climate benefits to be achieved at a lower 
cost, as long as offsets are additional and are not double-counted. 

Existing international programs to limit greenhouse gas emissions that 
allow the use of offsets for compliance may provide insights into trade-
offs between cost and credibility. For example, the European Union's 
program to limit greenhouse gas emissions enables regulated entities to 
use certain types of offsets for compliance. GAO is reviewing the 
European Union's program, including the role of offsets, in a report 
that we will issue later in 2008. 

Concluding Observations: 

The voluntary market for carbon offsets provides a potentially low-cost 
way for purchasers of offsets to compensate for their emissions of 
greenhouse gases by paying others to undertake activities that avoid, 
reduce, or sequester greenhouse gas emissions. However, several factors 
contribute to challenges in understanding the market. First, while most 
markets involve tangible goods or services, the carbon market involves 
a product that represents the absence of something--in this case, an 
offset equals the absence of one ton of carbon dioxide emissions. 
Second, ensuring the credibility of carbon offsets poses challenges 
because of the inherent uncertainty in measuring emissions reductions 
or sequestration relative to a projected business-as-usual scenario. 
Any measurement involving projections is inherently uncertain. These 
challenges are compounded by the fact that project developers produce 
offsets from a variety of activities--such as sequestration in 
agricultural soil, and forestry projects, and methane capture--and do 
not use a single set of commonly accepted quality assurance mechanisms. 
Third, many transactions do not involve a central trading platform, 
exchange, or registry system. These factors limit the market's 
transparency and pose challenges for market participants, especially 
consumers. 

Additional oversight of the voluntary market could address some of 
these challenges, but would also impose costs on government oversight 
bodies and increase costs for market participants. Some options for 
increased oversight include requiring the use of standard quality 
assurance mechanisms, mandating the use of a common registry, 
establishing product disclosure requirements that help consumers 
evaluate an offset's quality, establishing best practices, developing a 
government certification system, providing incentives or developing 
voluntary programs to encourage participants to take certain actions, 
and limiting the allowable types of activities that can generate 
offsets. Consideration of these approaches involves trade-offs among 
cost, quality assurance, and consumer protection. The Federal Trade 
Commission's efforts to update its Green Guides for environmental 
marketing claims may also enhance the existing oversight framework, 
which consists primarily of laws affecting contractual agreements and 
fraud. 

The options for enhanced oversight identified above may increase in 
importance in the context of a compliance market associated with any 
future policies that place binding limits on greenhouse gas emissions. 
While allowing carbon offsets for compliance with mandated reductions 
in emissions can decrease overall compliance costs for regulated 
entities, challenges with the credibility of offsets could compromise 
the integrity of a compliance scheme. In addition to the oversight 
options identified above, the government could consider further steps 
to address uncertainties with offsets such as limiting the extent of 
their use for compliance, discounting a percentage of all offsets, and 
imposing insurance requirements for offset providers and purchasers. 

Matter for Congressional Consideration: 

GAO is not recommending executive actions. However, as the Congress 
considers legislation intended to limit greenhouse gas emissions that 
allows the use of carbon offsets for compliance, it may wish to 
incorporate provisions that would direct the relevant federal agency 
(or agencies) to establish (1) clear rules about the types of offset 
projects that regulated entities can use, as well as standardized 
quality assurance mechanisms for these allowable project types; (2) 
procedures to account and compensate for the inherent uncertainty 
associated with offset projects, such as discounting or overall limits 
on the use of offsets for compliance; (3) a standardized registry for 
tracking the creation and ownership of offsets; and (4) procedures for 
amending the offset rules, quality assurance mechanisms, and registry, 
as necessary, based on experience and the availability of new 
information over time. 

As agreed with your offices, unless you publicly announce the contents 
of this report earlier, we plan no further distribution until 30 days 
from the report date. At that time, we will send copies to others who 
are interested and make copies available to others who request them. In 
addition, the report will be available at no charge on the GAO Web site 
at [hyperlink, http://www.gao.gov]. 

If you or your staff have any questions about this report, please 
contact me at (202) 512-3841 or stephensonj@gao.gov. Contact points for 
our Offices of Congressional Relations and Public Affairs may be found 
on the last page of this report. GAO staff who made major contributions 
to this report are listed in appendix VIII. 

Signed by: 

John B. Stephenson: 

Director, Natural Resources and Environment: 

List of Requesters: 

The Honorable Joe Barton: 
Ranking Member: 
Committee on Energy and Commerce: 
House of Representatives: 

The Honorable Tom Davis: 
Ranking Member: 
Committee on Oversight and Government Reform: 
House of Representatives: 

The Honorable Vernon J. Ehlers: 
Ranking Member: 
Committee on House Administration: 
House of Representatives: 

The Honorable Darrell Issa: 
Ranking Member: 
Subcommittee on Domestic Policy: 
Committee on Oversight and Government Reform: 
House of Representatives: 

The Honorable John Shimkus: 
Ranking Member: 
Subcommittee on Oversight and Investigations: 
Committee on Energy and Commerce: 
House of Representatives: 

[End of section] 

Appendix I: Objectives, Scope, and Methodology: 

This report examines (1) the scope of the U.S. voluntary carbon offset 
market, including the role of the federal government; (2) the extent to 
which mechanisms for ensuring the credibility of voluntary carbon 
offsets are available and used, and what, if any, related information 
is shared with consumers; and (3) the trade-offs associated with 
increasing the oversight of the U.S. voluntary carbon offset market and 
incorporating offsets into broader climate change mitigation policies. 

In conducting our work, we reviewed available government and trade 
literature related to carbon offset markets and conducted structured 
and open-ended interview questions with nonprobability samples of 34 
stakeholders, including 12 providers, 3 third party verifiers, 7 
developers of standards, and 12 other knowledgeable stakeholders. We 
selected nonprobability samples of relevant stakeholders based on 
analysis of existing market literature, referrals from other 
stakeholders, and other criteria, such as participation in carbon 
offset trade conferences.[Footnote 33] In general, we selected 
stakeholders that were frequently cited in available studies of the 
offset market or participated in related conferences and meetings, and 
preferentially selected stakeholders based in the United States. We 
also conducted scoping interviews with several trade groups and other 
knowledgeable stakeholders. 

To describe the scope of the U.S. voluntary carbon offset market, 
including the role of the federal government, we interviewed officials 
responsible for offset-related programs at the Department of 
Agriculture (Forest Service), the Department of Energy (Energy 
Information Administration), the Department of the Interior (U.S. Fish 
and Wildlife Service), and the Environmental Protection Agency, and 
officials at the Federal Trade Commission and the Commodity Futures 
Trading Commission. To obtain an official administration position on 
carbon offsets, we met with the Council on Environmental Quality. We 
attended public meetings and congressional briefings and attended 
several conferences focused on the voluntary carbon offset market. We 
met with officials responsible for managing state and regional 
greenhouse gas mitigation programs, including California's recently 
passed legislation to regulate greenhouse gases (Assembly Bill 32), the 
Regional Greenhouse Gas Initiative (RGGI), and the Western Climate 
Initiative. We met with representatives of the Chicago Climate 
Exchange, the Chief Administrative Officer of the House of 
Representatives, and other officials involved in the purchase of carbon 
offsets for the House of Representatives. To obtain perspectives on the 
role of the voluntary offset market in comparison and as a complement 
to compliance markets, we interviewed officials at the United Kingdom 
(UK) Department for Environment, Food and Rural Affairs (DEFRA). We 
also met with the UK National Audit Office, and a variety of other 
offset market participants and stakeholders in the UK. To obtain 
specific information about the supply of offsets in the United States, 
including the number and type of offset projects and the quantity of 
offsets by state, we analyzed data purchased from Point Carbon, a 
provider of independent news, analysis, and consulting services for 
European and global power, gas, and carbon markets. Data presented in 
this report on the supply of offsets refer specifically to offsets 
generated from projects located in the United States. Point Carbon 
estimates that its database accounts for approximately 80 percent of 
the offsets generated from projects located in the United States based 
on its analysis of domestic and global carbon markets. As such, our 
analysis may not have included all projects that are operating in the 
United States; however, we believe these data represent the best 
information available. To assess the reliability of the Point Carbon 
data, we (1) performed electronic testing of required data elements, 
(2) reviewed existing information about the data and the system that 
produced them, and (3) interviewed Point Carbon staff who are 
knowledgeable about the data. We determined that the data were 
sufficiently reliable for the purposes of this report. 

To analyze the extent to which mechanisms for ensuring the credibility 
of voluntary carbon offsets are available and used, and what, if any, 
related information is shared with consumers, we obtained about $100 
worth of offsets from each of a nonprobability sample of 33 retail 
providers for a total expenditure of approximately $3,300. The 
information we obtained from the nonprobability sample of purchases 
does not address how the market may evolve over time or how consumers 
interpret the information they receive from providers. To select the 
sample of retailers from whom offsets would be obtained, we used 
available information to identify providers that sold or accepted 
donations for offsets online. To select the sample of retailers, we 
developed a list of providers based on primary sources, including 
reports, studies, surveys, and lists from membership organizations. We 
used information from providers' Web sites to identify whether 
providers sold or accepted donations for offsets online and selected 
retailers that did and were identified in two or more primary sources. 
We conducted online transactions because they cater directly to 
individual consumers, a portion of the U.S. voluntary carbon offset 
market that is not well characterized in available studies. We analyzed 
the documentation directly related to each transaction, including (1) 
transaction documents--information provided while conducting the online 
transaction, (2) e-mail documents--any information received through e-
mail after conducting the transaction, and (3) mail documents--any 
information received through the mail after conducting the transaction. 
We analyzed the documentation directly related to the transaction, if 
provided, to determine whether it contained information related to 
volume, price, project type and location, standards, registry, 
verification, monitoring, additionality, timing, and ownership. We also 
reviewed information presented on the retailer's Web site to determine 
whether information was provided about the retailers' offsets related 
to price, project type and location, standards, registry, verification, 
monitoring, additionality, timing, and ownership. 

To assess the trade-offs associated with increasing the oversight of 
the U.S. voluntary carbon offset market and incorporating offsets into 
broader climate change mitigation policies, we reviewed available 
economic literature and information collected through stakeholder 
responses to structured and open-ended interview questions. We 
conducted our work from July 2007 to August 2008. 

[End of section] 

Appendix II: Description of Offset Project Types: 

Project type: Agricultural methane; 
Description: Projects that capture and combust or contain methane 
produced from agricultural operations. This involves the installation 
of complete-mix or plug-flow digesters or lagoon covers that collect 
aggregated waste from dairy, avian, and/ or hog sources. 

Project type: Agricultural soil; 
Description: Projects that sequester carbon in soil through the 
adoption of conservation tillage and activities such as planting grass 
or adopting certain tilling practices. 

Project type: Carbon capture and biological storage (CCBS); 
Description: Projects that capture and sequester greenhouse gases using 
biological techniques such as algae lagoons. 

Project type: Carbon capture and geological storage (CCGS); 
Description: Projects that separate CO2 emissions from industrial and 
energy-related emissions sources, transport the CO2 to a suitable 
storage site, and then isolate the CO2 by injecting it into an 
underground geologic formation such as active and abandoned oil and gas 
reservoirs, saline aquifers, or unminable coal seams. 

Project type: Coal mine methane; 
Description: Projects that capture and burn or contain methane emitted 
by coal mines. 

Project type: Energy efficiency; 
Description: Projects that reduce CO2 emissions by reducing on-site 
combustion of natural gas, oil, or propane for end use by improving the 
energy efficiency of fuel usage and/or the energy efficient delivery of 
energy services. 

Project type: Forestry; 
Description: Projects that occur on land managed in accordance with 
sustainable forestry practices and promote the restoration of native 
forests by using mainly native species and avoiding the introduction of 
invasive nonnative species. 

Project type: Landfill methane; 
Description: Projects that capture and burn or contain methane produced 
by landfills. 

Project type: Rangeland soil; 
Description: Projects that involve the adoption of certain sustainable 
grazing practices on rangeland that include moderate livestock density 
and rotational and seasonal grazing techniques. 

Project type: Renewable energy; 
Description: Projects that reduce emissions by generating energy from 
renewable sources including but not limited to hydro, wind, and solar 
power. 

Project type: Renewable energy certificates (REC); 
Description: RECs are tradable certificates that represent the 
environmental attributes that result from one megawatt hour of 
electricity generated by a renewable source, such as wind power. 

Source: GAO. 

[End of table] 

[End of section] 

Appendix III: Volume and Number of Offset Projects by State in 2007: 

Range: More than 250,000; 
State: Texas; 
Volume: 1,830,258; 
Percentage of total volume: 18; 
Number of projects: 12. 

Range: More than 250,000; 
State: Virginia; 
Volume: 1,680,500; 
Percentage of total volume: 16; 
Number of projects: 2. 

Range: More than 250,000; 
State: Multiple States; 
Volume: 727,313; 
Percentage of total volume: 7; 
Number of projects: 12. 

Range: More than 250,000; 
State: Wyoming; 
Volume: 606,082; 
Percentage of total volume: 6; 
Number of projects: 4. 

Range: More than 250,000; 
State: Georgia; 
Volume: 532,779; 
Percentage of total volume: 5; 
Number of projects: 5. 

Range: More than 250,000; 
State: Alabama; 
Volume: 500,000; 
Percentage of total volume: 5; 
Number of projects: 2. 

Range: More than 250,000; 
State: Illinois; 
Volume: 464,284; 
Percentage of total volume: 5; 
Number of projects: 11. 

Range: More than 250,000; 
State: California; 
Volume: 407,125; 
Percentage of total volume: 4; 
Number of projects: 31. 

Range: More than 250,000; 
State: Colorado; 
Volume: 403,000; 
Percentage of total volume: 4; 
Number of projects: 2. 

Range: More than 250,000; 
State: North Dakota; 
Volume: 400,000; 
Percentage of total volume: 4; 
Number of projects: 2. 

Range: More than 250,000; 
State: Wisconsin; 
Volume: 294,263; 
Percentage of total volume: 3; 
Number of projects: 13. 

Range: 100,000 to 250,000; 
State: Pennsylvania; 
Volume: 188,063; 
Percentage of total volume: 2; 
Number of projects: 13. 

Range: 100,000 to 250,000; 
State: North Carolina; 
Volume: 181,365; 
Percentage of total volume: 2; 
Number of projects: 3. 

Range: 100,000 to 250,000; 
State: Washington; 
Volume: 174,080; 
Percentage of total volume: 2; 
Number of projects: 3. 

Range: 100,000 to 250,000; 
State: Oregon; 
Volume: 168,663; 
Percentage of total volume: 2; 
Number of projects: 11. 

Range: 100,000 to 250,000; 
State: New Hampshire; 
Volume: 156,125; 
Percentage of total volume: 2; 
Number of projects: 2. 

Range: 100,000 to 250,000; 
State: Louisiana; 
Volume: 150,558; 
Percentage of total volume: 1; 
Number of projects: 11. 

Range: 100,000 to 250,000; 
State: New York; 
Volume: 149,407; 
Percentage of total volume: 1; 
Number of projects: 8. 

Range: 100,000 to 250,000; 
State: Utah; 
Volume: 121,000; 
Percentage of total volume: 1; 
Number of projects: 3. 

Range: 100,000 to 250,000; 
State: Mississippi; 
Volume: 108,340; 
Percentage of total volume: 1; 
Number of projects: 6. 

Range: 100,000 to 250,000; 
State: Indiana; 
Volume: 106,800; 
Percentage of total volume: 1; 
Number of projects: 1. 

Range: 25,000 to 99,999; 
State: New Jersey; 
Volume: 96,853; 
Percentage of total volume: <1; 
Number of projects: 6. 

Range: 25,000 to 99,999; 
State: Michigan; 
Volume: 94,691; 
Percentage of total volume: <1; 
Number of projects: 5. 

Range: 25,000 to 99,999; 
State: Montana; 
Volume: 80,410; 
Percentage of total volume: <1; 
Number of projects: 5. 

Range: 25,000 to 99,999; 
State: Oklahoma; 
Volume: 77,335; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: 25,000 to 99,999; 
State: Maryland; 
Volume: 75,000; 
Percentage of total volume: <1; 
Number of projects: 1. 

Range: 25,000 to 99,999; 
State: Minnesota; 
Volume: 72,165; 
Percentage of total volume: <1; 
Number of projects: 5. 

Range: 25,000 to 99,999; 
State: Delaware; 
Volume: 60,000; 
Percentage of total volume: <1; 
Number of projects: 1. 

Range: 25,000 to 99,999; 
State: Maine; 
Volume: 55,000; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: 25,000 to 99,999; 
State: Massachusetts; 
Volume: 53,405; 
Percentage of total volume: <1; 
Number of projects: 1. 

Range: 25,000 to 99,999; 
State: Iowa; 
Volume: 42,374; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: 25,000 to 99,999; 
State: Idaho; 
Volume: 40,773; 
Percentage of total volume: <1; 
Number of projects: 3. 

Range: 25,000 to 99,999; 
State: Missouri; 
Volume: 40,000; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: 25,000 to 99,999; 
State: Kentucky: Tennessee; 
Volume: 31,773; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: Less than 25,000; 
State: Kentucky; 
Volume: 18,400; 
Percentage of total volume: <1; 
Number of projects: 4. 

Range: Less than 25,000; 
State: Arkansas; 
Volume: 12,550; 
Percentage of total volume: <1; 
Number of projects: 6. 

Range: Less than 25,000; 
State: South Dakota; 
Volume: 6,084; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: Less than 25,000; 
State: Vermont; 
Volume: 1,639; 
Percentage of total volume: <1; 
Number of projects: 2. 

Range: Less than 25,000; 
State: Alaska; 
Volume: 360; 
Percentage of total volume: <1; 
Number of projects: 1. 

Range: Less than 25,000; 
State: Florida; 
Volume: 130; 
Percentage of total volume: <1; 
Number of projects: 1. 

Range: Less than 25,000; 
State: Hawaii; 
Volume: 90; 
Percentage of total volume: <1; 
Number of projects: 1. 

Range: Less than 25,000; 
State: Arizona; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: Connecticut; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: District of Columbia; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: Kansas; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: Nebraska; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: Nevada; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: New Mexico; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: Ohio; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: Rhode Island; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: South Carolina; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Range: Less than 25,000; 
State: West Virginia; 
Volume: 0; 
Percentage of total volume: 0; 
Number of projects: 0. 

Source: GAO analysis of Point Carbon data. 

[A] Twelve projects occur across multiple states. The data for these 
projects are included under the category of multiple states and not 
included in the volume or number of projects for the individual states 
involved in these projects. 

[End of table] 

[End of section] 

Appendix IV: Description of the Purchase of Carbon Offsets by the Chief 
Administrative Officer of the House of Representatives: 

On March 1, 2007, the Speaker and Majority Leader of the U.S. House of 
Representatives and Chairwoman of the Committee on House Administration 
directed the House Chief Administrative Officer (CAO) to develop a 
Green the Capitol Initiative to provide an environmentally responsible 
and healthy working environment for House employees. Among other 
measures, the CAO's June 21, 2007, report recommended that the House 
operate in a carbon neutral manner by the end of the 110th Congress and 
identified three strategies to achieve this goal, including (1) 
purchasing electricity generated from renewable sources; (2) meeting 
the House's heating and cooling needs by switching from using coal, 
oil, and natural gas at the Capitol power plant to natural gas only; 
and (3) purchasing offsets to compensate for any remaining carbon 
emissions. According to the CAO, using strategies one and two, the 
House would need to offset 24,000 short tons of carbon dioxide 
emissions to operate in a carbon neutral manner.[Footnote 34] 

The CAO recommended purchasing carbon offsets through the Chicago 
Climate Exchange (CCX), a voluntary greenhouse gas reduction and 
trading system through which members make commitments to decrease their 
emissions. If CCX members reduce emissions beyond their reduction 
goals, they may sell the extra reductions to other members of the 
exchange. In addition to emitting members, the CCX platform is also 
available to offset providers, who may register tons on CCX that 
represent greenhouse gas mitigation projects. To meet their 
commitments, CCX members may trade emissions reductions or offsets 
known as Carbon Financial Instruments (CFI).[Footnote 35] According to 
CCX, to verify the validity of offsets offered for sale on the 
exchange, and ensure that the underlying offset projects conform to CCX 
rules, all tons registered for sale on the CCX platform from offset 
projects must have been verified by CCX-approved outside verifier firms 
that are specialized in particular fields. The outside verification 
firms are to ensure that the projects are in accordance with CCX 
eligibility rules and methodologies, verify that projects have been 
implemented, conduct on-site inspections, and send verification reports 
to CCX. CCX staff and, in certain cases, the CCX Offsets Committee, 
review the verification reports and request corrective actions, if 
necessary. After completion of any corrective actions, CCX sends the 
verification reports to the Financial Industry Regulatory Authority 
(FINRA) for a final review to ensure project verification documentation 
is complete.[Footnote 36] Uniquely serialized Carbon Financial 
Instruments based on these offsets are then issued to the project 
owner's CCX registry account, and may then be sold in the CCX market. 
The market participants' registry accounts help the market participant 
track purchases and sales of offsets acquired or sold on the exchange 
that can be used to identify specific information about the offset 
projects, including verification documents. According to CCX, all 
participants have the option of buying CFIs anonymously and all 
transaction prices must be reported so that CCX can post prices on its 
trading platform. 

The House Appropriations Committee, in its June 19, 2007, report on the 
2008 Legislative Branch Appropriations Bill, stated: "The Committee 
believes it is important to offset greenhouse gases generated by the 
House. In that regard, the Committee requests the Chief Administrative 
Officer purchase Carbon Financial Instruments to offset carbon produced 
by all House operations. These offsets should be fully transparent, 
verified, American, project-based offset credits."[Footnote 37] The CAO 
requested and received approval from the Committee on House 
Administration on August 29, 2007, to purchase offsets and submit an 
application to CCX with the necessary fee. According to CAO officials, 
CCX was the best option for the House because it is well established 
relative to the rest of the industry, has clear verification and 
monitoring standards, and allows for the anonymous purchase of offsets. 
The CAO requested that CCX conduct a blind auction because the CAO did 
not want to decide or know which projects were selected. According to 
the CAO, this approach was adopted to eliminate any opportunity for 
House funds to be used to benefit one geographical region or 
congressional district over another. For example, the CAO decided not 
to purchase offsets on the retail market from domestic nonprofit groups 
because a decision to select specific vendors or offset projects in one 
location instead of another could be construed as a political act. On 
October 23, 2007, CCX made a public announcement to potential sell-side 
market participants that it would hold the reverse auction on behalf of 
the House of Representatives and stipulated that the projects sought 
had to be verified and approved CCX projects undertaken in the United 
States. The auction closed on November 1, resulting in the purchase of 
30,000 metric tons for a total of $90,550 including transaction fees. 
Results of the auction were announced at a public ceremony on November 
5, 2007. 

The CAO bought offsets before implementing the emissions reduction 
strategies specified in the Green the Capitol Initiative. Based on 
calculations performed for the Green the Capitol Initiative report by 
the Department of Energy and the Lawrence Berkeley National Laboratory, 
the carbon footprint of the House is approximately 91,000 short tons. 
According to the CAO, until the Architect of the Capitol's metering 
program is complete, in March 2009, House emissions data are based on 
historical estimates. To reach the goal of carbon neutrality, the Green 
the Capitol Initiative called for two emissions reduction strategies 
and the purchase of carbon offsets to compensate for whatever emissions 
remained. Purchasing electricity generated from renewable sources would 
decrease emissions to 34,000 short tons. Switching from burning coal, 
oil, and natural gas at the Capitol power plant to burning only natural 
gas would further decrease emissions to 24,000 short tons. The third 
strategy to reach the goal of carbon neutrality was to purchase offsets 
for the remaining carbon emissions--24,000 short tons. However, the 
first two strategies had not been completed when the CAO purchased 
offsets through CCX in November 2007. Concerning the first two 
strategies, the Architect of the Capitol purchased renewable energy in 
June 2008, and the CAO, in written comments, told us that the Architect 
of the Capitol had purchased natural gas to account for the House's 
portion of energy used at the Capitol Power Plant. According to the 
CAO, there was no benefit to waiting to purchase offsets. 

The CAO used data from 2006 that GAO developed as part of a broader 
characterization of greenhouse gas emissions from legislative branch 
agencies and later analyzed by Lawrence Berkeley National Laboratory to 
identify the amount of offsets the CAO would purchase to reach its goal 
of carbon neutrality by the end of 2008.[Footnote 38] The CAO stated 
that it does not have current emissions data and that the Architect of 
the Capitol does not have meters that enable it to directly monitor its 
energy use or emissions in real time. According to the CAO, emissions 
data projected from a 2006 baseline provide a reasonable estimate of 
current emissions. 

In November 2007, the CAO purchased 30,000 metric tons of offsets 
through CCX, which is more than the 24,000 short tons identified in the 
Green the Capitol Initiative report and a memorandum approving the 
CAO's Chicago Climate Exchange application, which was signed by the 
Committee on House Administration in August 2007.[Footnote 39] The CAO 
purchased approximately 9,075 short tons (about 8,231 metric tons), 
more than identified in the Green the Capitol Initiative, an amount 
valued at about $24,447 based on the weighted average purchase price of 
$2.97 per metric ton paid by the CAO.[Footnote 40] According to the 
House CAO and CCX, the purchase of additional tons was an 
administrative error that resulted from the difference between short 
and metric tons and reference to the draft report rather than the final 
report.[Footnote 41] An April 2007 draft of the Green the Capitol 
Initiative report identified the need to purchase 34,000 tons, but the 
June 2007 final report identified the need to purchase 24,000 short 
tons. On March 27, 2008, the CAO requested that CCX retire 24,000 of 
the 30,000 metric tons.[Footnote 42] Currently, 6,000 metric tons 
remain in the CAO's registry account, which, according to the CAO, may 
be used to offset additional emissions generated by the operation of 
the House. The CAO said that the initial purchase of carbon offsets was 
an approximation and plans to reconcile the purchase in fiscal year 
2009. 

Because it retired 24,000 metric tons instead of short tons, the CAO 
retired about 2,460 short tons (about 2,231 metric tons) more than 
identified in the Green the Capitol Initiative report. These extra tons 
are valued at about $6,626 based on the CAO's purchase price. According 
to the CAO, the retirement of extra tons may address uncertainties in 
the emissions calculations used to determine the amount of offsets to 
purchase. 

Following the auction, the CAO received information from CCX about the 
number and types of projects underlying its purchase. No other 
information was provided by CCX or requested by the CAO. The offsets 
purchased by the CAO came from a variety of project types, including 
agricultural methane, agricultural soil sequestration, coal mine 
methane, landfill methane, and renewable energy. The CCX auction notice 
required that offsets submitted to the auction originate from U.S.- 
based projects, and CCX officials said that they screened the registry 
accounts of auction participants to confirm that the sellers' offsets 
were from U.S.-based projects. Registry accounts maintained by CCX for 
market participants track the type of information necessary to satisfy 
the criteria directed by the appropriations committee report. Thus, the 
CAO could verify that the offsets met the criteria, if necessary. The 
CAO can also request that CCX provide additional quality assurance 
documentation, including detailed verification reports. 

[End of section] 

Appendix V: Summary of Stakeholder Responses to Interview Questions: 

Table 3: Stakeholders' Rating of Carbon Offset Market Challenges: 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Additionality; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 8; 
(2) Moderately challenging: 5; 
(3) Very challenging: 13; 
(4) Extremely challenging: 7; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 2.58. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Many different 
verification and monitoring methodologies; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 4; 
(2) Moderately challenging: 13; 
(3) Very challenging: 9; 
(4) Extremely challenging: 7; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 2.58. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Press coverage 
of offsets; 
(0) Not at all challenging: 2; 
(1) Slightly challenging: 4; 
(2) Moderately challenging: 10; 
(3) Very challenging: 8; 
(4) Extremely challenging: 8; 
Don't know/ unsure: 1; 
Total responses[A]: 33; 
Average[B]: 2.50. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Education; 
(0) Not at all challenging: 1; 
(1) Slightly challenging: 3; 
(2) Moderately challenging: 15; 
(3) Very challenging: 11; 
(4) Extremely challenging: 3; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 2.36. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Permanence; 
(0) Not at all challenging: 1; 
(1) Slightly challenging: 8; 
(2) Moderately challenging: 11; 
(3) Very challenging: 11; 
(4) Extremely challenging: 2; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 2.15. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Baseline 
quantification methodologies; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 4; 
(2) Moderately challenging: 22; 
(3) Very challenging: 7; 
(4) Extremely challenging: 0; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 2.09. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Transaction 
costs associated with quantification, verification, and monitoring; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 9; 
(2) Moderately challenging: 13; 
(3) Very challenging: 8; 
(4) Extremely challenging: 2; 
Don't know/ unsure: 1; 
Total responses[A]: 33; 
Average[B]: 2.09. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Leakage; 
(0) Not at all challenging: 1; 
(1) Slightly challenging: 9; 
(2) Moderately challenging: 16; 
(3) Very challenging: 4; 
(4) Extremely challenging: 3; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 1.97. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Reduction 
quantification methodologies; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 6; 
(2) Moderately challenging: 23; 
(3) Very challenging: 4; 
(4) Extremely challenging: 0; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 1.94. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Liability; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 12; 
(2) Moderately challenging: 13; 
(3) Very challenging: 2; 
(4) Extremely challenging: 3; 
Don't know/ unsure: 3; 
Total responses[A]: 33; 
Average[B]: 1.87. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Timing of 
reductions (future, past); 
(0) Not at all challenging: 5; 
(1) Slightly challenging: 10; 
(2) Moderately challenging: 11; 
(3) Very challenging: 5; 
(4) Extremely challenging: 1; 
Don't know/ unsure: 1; 
Total responses[A]: 33; 
Average[B]: 1.59. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Establishment 
of ownership; 
(0) Not at all challenging: 0; 
(1) Slightly challenging: 18; 
(2) Moderately challenging: 9; 
(3) Very challenging: 3; 
(4) Extremely challenging: 1; 
Don't know/ unsure: 2; 
Total responses[A]: 33; 
Average[B]: 1.58. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Finding / 
matching buyers and sellers; 
(0) Not at all challenging: 7; 
(1) Slightly challenging: 9; 
(2) Moderately challenging: 12; 
(3) Very challenging: 3; 
(4) Extremely challenging: 0; 
Don't know/ unsure: 1; 
Total responses[A]: 32; 
Average[B]: 1.35. 

How challenging, if at all, are each of the following for the effective 
functioning of the U.S. voluntary carbon offset market?: Many different 
types of projects; 
(0) Not at all challenging: 8; 
(1) Slightly challenging: 15; 
(2) Moderately challenging: 5; 
(3) Very challenging: 4; 
(4) Extremely challenging: 1; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 1.24. 

Source: GAO. 

[A] The total column represents the number of stakeholders that 
answered each question with a single answer. 

[B] The average column represents the average of the numerical ratings 
submitted by stakeholders for (0) Not at all challenging through (4) 
Extremely challenging. The average does not include responses for Don't 
know/ unsure, because this is not a numerical rating. 

[End of table] 

Table 4: Stakeholders' Rating of Characteristics of Offset Credibility: 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Additionality; 
(0) Not at all important: 1; 
(1) Slightly important: 1; 
(2) Moderately important: 2; 
(3) Very important: 3; 
(4) Extremely important: 26; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 3.58. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Transparency; 
(0) Not at all important: 0; 
(1) Slightly important: 0; 
(2) Moderately important: 0; 
(3) Very important: 14; 
(4) Extremely important: 19; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 3.58. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Permanence; 
(0) Not at all important: 0; 
(1) Slightly important: 1; 
(2) Moderately important: 2; 
(3) Very important: 8; 
(4) Extremely important: 22; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 3.55. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Verification and monitoring; 
(0) Not at all important: 0; 
(1) Slightly important: 0; 
(2) Moderately important: 3; 
(3) Very important: 9; 
(4) Extremely important: 21; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 3.55. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Use of registry to avoid double- 
counting; 
(0) Not at all important: 0; 
(1) Slightly important: 0; 
(2) Moderately important: 4; 
(3) Very important: 12; 
(4) Extremely important: 16; 
Don't know/ unsure: 1; 
Total responses[A]: 33; 
Average[B]: 3.38. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Established ownership; 
(0) Not at all important: 0; 
(1) Slightly important: 2; 
(2) Moderately important: 6; 
(3) Very important: 10; 
(4) Extremely important: 15; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 3.15. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Clear institutional arrangement; 
(0) Not at all important: 1; 
(1) Slightly important: 2; 
(2) Moderately important: 7; 
(3) Very important: 7; 
(4) Extremely important: 10; 
Don't know/ unsure: 5; 
Total responses[A]: 32; 
Average[B]: 2.85. 

How important, if at all, are each of the following for establishing 
the credibility of a carbon offset?: Reputation of offset provider; 
(0) Not at all important: 1; 
(1) Slightly important: 3; 
(2) Moderately important: 11; 
(3) Very important: 9; 
(4) Extremely important: 9; 
Don't know/ unsure: 0; 
Total responses[A]: 33; 
Average[B]: 2.67. 

Source: GAO. 

[A] The total column represents the number of stakeholders that 
answered each question with a single answer. 

[B] The average column represents the average of the numerical ratings 
submitted by stakeholders for (0) Not at all important through (4) 
Extremely important. The average does not include responses for Don't 
know/ unsure, because this is not a numerical rating. 

[End of table] 

Table 5: Stakeholders' Rating of the Credibility of Different Types of 
Carbon Offset Projects: 

How credible, if at all, is each type of project?: Agriculture methane; 
(0) Not at all credible: 0; 
(1) Slightly credible: 1; 
(2) Moderately credible: 1; 
(2) Moderately credible: 8; 
(4) Extremely credible: 12; 
Varies: 9; 
Don't know/ unsure: 0; 
Total responses[A]: 31; 
Average[B]: 3.41. 

How credible, if at all, is each type of project?: Fuel switch; 
(0) Not at all credible: 0; 
(1) Slightly credible: 0; 
(2) Moderately credible: 3; 
(2) Moderately credible: 5; 
(4) Extremely credible: 10; 
Varies: 12; 
Don't know/ unsure: 1; 
Total responses[A]: 31; 
Average[B]: 3.39. 

How credible, if at all, is each type of project?: Landfill methane; 
(0) Not at all credible: 0; 
(1) Slightly credible: 1; 
(2) Moderately credible: 3; 
(2) Moderately credible: 6; 
(4) Extremely credible: 10; 
Varies: 10; 
Don't know/ unsure: 1; 
Total responses[A]: 31; 
Average[B]: 3.25. 

How credible, if at all, is each type of project?: Coal mine methane; 
(0) Not at all credible: 0; 
(1) Slightly credible: 4; 
(2) Moderately credible: 2; 
(2) Moderately credible: 4; 
(4) Extremely credible: 7; 
Varies: 10; 
Don't know/ unsure: 4; 
Total responses[A]: 31; 
Average[B]: 2.82. 

How credible, if at all, is each type of project?: Industrial gas; 
(0) Not at all credible: 1; 
(1) Slightly credible: 0; 
(2) Moderately credible: 7; 
(2) Moderately credible: 2; 
(4) Extremely credible: 7; 
Varies: 11; 
Don't know/ unsure: 2; 
Total responses[A]: 30; 
Average[B]: 2.82. 

How credible, if at all, is each type of project?: Non-REC renewable 
energy; 
(0) Not at all credible: 1; 
(1) Slightly credible: 2; 
(2) Moderately credible: 3; 
(2) Moderately credible: 8; 
(4) Extremely credible: 4; 
Varies: 11; 
Don't know/ unsure: 1; 
Total responses[A]: 30; 
Average[B]: 2.67. 

How credible, if at all, is each type of project?: Energy efficiency; 
(0) Not at all credible: 2; 
(1) Slightly credible: 2; 
(2) Moderately credible: 5; 
(2) Moderately credible: 6; 
(4) Extremely credible: 6; 
Varies: 10; 
Don't know/ unsure: 0; 
Total responses[A]: 31; 
Average[B]: 2.57. 

How credible, if at all, is each type of project?: Afforestation; 
(0) Not at all credible: 2; 
(1) Slightly credible: 1; 
(2) Moderately credible: 4; 
(2) Moderately credible: 5; 
(4) Extremely credible: 4; 
Varies: 14; 
Don't know/ unsure: 1; 
Total responses[A]: 31; 
Average[B]: 2.5. 

How credible, if at all, is each type of project?: Reforestation; 
(0) Not at all credible: 2; 
(1) Slightly credible: 2; 
(2) Moderately credible: 5; 
(2) Moderately credible: 3; 
(4) Extremely credible: 6; 
Varies: 13; 
Don't know/ unsure: 0; 
Total responses[A]: 31; 
Average[B]: 2.5. 

How credible, if at all, is each type of project?: Avoided 
deforestation; 
(0) Not at all credible: 1; 
(1) Slightly credible: 4; 
(2) Moderately credible: 5; 
(2) Moderately credible: 2; 
(4) Extremely credible: 4; 
Varies: 14; 
Don't know/ unsure: 1; 
Total responses[A]: 31; 
Average[B]: 2.25. 

How credible, if at all, is each type of project?: Agriculture soil 
carbon; 
(0) Not at all credible: 0; 
(1) Slightly credible: 10; 
(2) Moderately credible: 5; 
(2) Moderately credible: 5; 
(4) Extremely credible: 1; 
Varies: 9; 
Don't know/ unsure: 1; 
Total responses[A]: 31; 
Average[B]: 1.86. 

How credible, if at all, is each type of project?: Rangeland soil 
carbon; 
(0) Not at all credible: 1; 
(1) Slightly credible: 8; 
(2) Moderately credible: 7; 
(2) Moderately credible: 4; 
(4) Extremely credible: 1; 
Varies: 9; 
Don't know/ unsure: 1; 
Total responses[A]: 31; 
Average[B]: 1.81. 

How credible, if at all, is each type of project?: Renewable energy 
certificates (REC); 
(0) Not at all credible: 9; 
(1) Slightly credible: 3; 
(2) Moderately credible: 2; 
(2) Moderately credible: 3; 
(4) Extremely credible: 2; 
Varies: 12; 
Don't know/ unsure: 0; 
Total responses[A]: 31; 
Average[B]: 1.26. 

Source: GAO. 

Notes: The answers provided by stakeholders represent their ratings at 
a particular point in time and may not reflect the development of new 
mechanisms to ensure the credibility of offsets. Several stakeholders 
commented that any project, properly constructed, can generate 
acceptable offsets. They said that there are issues that make some 
project types easier to develop than others, but that does not mean 
that acceptable quantification methodologies cannot or will not be 
developed. 

[A] The total column represents the number of stakeholders that 
answered each question with a single answer. 

[B] The average column represents the average of the numerical ratings 
submitted by stakeholders for (0) Not at all credible through (4) 
Extremely credible. The average does not include responses for Varies 
and Don't know/ unsure because these are not numerical ratings. 

[End of table] 

[End of section] 

Appendix VI: Summaries of Selected International, Regional, and State 
Programs: 

California Global Warming Solutions Act (Assembly Bill [AB] 32); 
On September 27, 2006, the California Global Warming Solutions Act was 
signed into law. The act requires the California Air Resources Board 
(ARB) to establish a program to reduce the state's emissions to 1990 
levels by 2020. On June 26, 2008, ARB released a draft scoping plan for 
public comment that contains the strategies California will use to 
reduce emissions of greenhouse gases. The draft includes a discussion 
of the potential role of offsets in implementing AB 32. Specific 
commitments on the role of offsets in AB 32 will be available in a 
revised scoping plan that ARB will publish in early October 2008 for 
comment. This version of the plan will be presented to the Air 
Resources Board in November 2008 for possible adoption by the board. AB 
32 requires the board to adopt a scoping plan by January 1, 2009. 
Regulations based on the final scoping plan must be adopted by January 
1, 2011, and are to become effective on January 1, 2012. More 
information about implementation of the California Global Warming 
Solutions Act is available at [hyperlink, 
http://www.arb.ca.gov/cc/cc.htm]. 

European Union Emissions Trading Scheme (EU ETS); 
The European Union Emission Trading Scheme is a cap-and-trade system in 
which energy- intensive industries in the European Union buy or sell 
emission allowances to help meet member states' commitments under the 
Kyoto Protocol. The EU ETS covers over 11,000 electricity-generating 
facilities and energy-intensive installations, such as oil refineries 
and steel plants, in 27 member countries. The EU ETS enables regulated 
entities to use certain types of offsets for compliance. In some cases, 
regulated entities may choose to comply with emissions limits by 
purchasing offsets rather than by reducing their own emissions. Limits 
for the use of offsets vary by country, with a range from zero to 20 
percent of a country's total cap, and an average limit of 11 percent. 
These limits apply to the current Phase II of the EU ETS and may change 
in Phase III, which begins in 2013. For more information about the EU 
ETS, see http://ec.europa.eu/environment/climat/emission.htm. 

Midwestern Greenhouse Gas Reduction Accord; 
The governors of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, 
Ohio, South Dakota, and Wisconsin, and the premiers of the Canadian 
provinces of Manitoba and Ontario participate or observe in the 
Midwestern Greenhouse Gas Reduction Accord, an agreement to establish 
greenhouse gas reduction targets and time frames, and to develop market-
based mechanisms to reach these targets. The accord was established in 
November 2007. An offsets subgroup is expected to make recommendations 
about the role of offsets in a regional emissions reduction program by 
September 2008, according the subgroup's work plan. More information 
about the Midwestern Greenhouse Gas Reduction Accord is available at 
[hyperlink, http://www.midwesternaccord.org/]. 

Regional Greenhouse Gas Initiative (RGGI); 
The Regional Greenhouse Gas Initiative is a cooperative effort by 
Northeast and Mid-Atlantic states to design a regional cap-and-trade 
program initially covering carbon dioxide emissions from power plants 
in the region. Connecticut, Delaware, Maine, Maryland, Massachusetts, 
New Hampshire, New Jersey, New York, Rhode Island, and Vermont are 
participating in the RGGI effort. The District of Columbia, 
Pennsylvania, Ontario, Quebec, the Eastern Canadian Provinces, and New 
Brunswick are observers in the process. On August 15, 2006, the 
participating states issued a model rule that details the proposed RGGI 
program. Offset projects included in the program are initially limited 
to five types of projects, including landfill methane capture and 
sequestration, because these types occur within the borders of the RGGI 
states, among other factors. The model rule specifies offset project 
requirements including criteria for additionality, quantification and 
verification of emissions reductions, independent verification, and 
accreditation standards for independent verifiers. Each source required 
to reduce emissions would generally be able to use offsets to comply 
with up to 3.3 percent of its obligation in a single compliance period. 
If the compliance price hits certain levels, the use of offsets may 
increase to 5 or 10 percent of required reductions. The first 3-year 
compliance period will begin January 1, 2009. More information about 
RGGI is available at [hyperlink, http://www.rggi.org/index.htm]. 

United Kingdom Department for Environment, Food and Rural Affairs 
(DEFRA); 
On February 19, 2008, the United Kingdom (UK) Department for 
Environment, Food and Rural Affairs announced the framework for the 
Code of Best Practice for Carbon Offsetting to provide UK consumers 
with guidance on carbon offsets. The code is designed to increase 
consumers' understanding of offsetting and its role in addressing 
climate change, increase consumer confidence in the integrity and value 
for money of the offset products available to them, and to provide 
signals to the UK offset sector on the quality and verification 
standards to which they should aspire. Offset products meeting the 
specifications of the code will be assigned with a certification mark, 
which providers may use on their Web sites and other materials. The 
code is voluntary and offset providers can choose whether to seek 
accreditation for all, or some, of their offsetting products. The code 
initially covers only Certified Emissions Reductions (CER), that are 
compliant with the Kyoto Protocol, because there is currently no 
definition or fully established common standard for voluntary offsets. 
DEFRA has asked the voluntary offset industry to jointly develop a 
standard that could be included in the code in the future. For more 
information about the DEFRA Code of Best Practice for Carbon Offsetting 
see [hyperlink, 
http://www.defra.gov.uk/environment/climatechange/uk/carbonoffset/ 
index.htm]. 

Western Climate Initiative (WCI); 
The Western Climate Initiative was launched in February 2007 by the 
governors of Arizona, California, New Mexico, Oregon, and Washington to 
develop regional strategies to address climate change. Partners in the 
Initiative also include Montana, Utah, and the Canadian provinces of 
British Columbia, Ontario, Quebec, and Manitoba. Other U.S. and Mexican 
states have joined as observers. The WCI regional greenhouse gas 
emission reduction goal is an aggregate reduction of 15 percent below 
2005 levels by 2020. On May 16, 2008, the WCI released recommendations 
about how to structure the region's cap-and-trade emissions reduction 
program, including a series of recommendations about how to incorporate 
offsets into such a program. A more detailed version of the draft 
offset recommendations was released in July 2008, and WCI is striving 
to reach a final agreement on overall program design in August 2008. 
More information about the WCI draft design recommendations on offsets 
is available at [hyperlink, http://www.westernclimateinitiative.org/]. 

Source: GAO. 

[End of table] 

[End of section] 

Appendix VII: Selected Carbon Offset Standards: 

Standard: The California Climate Action Registry; 
Description: The California Registry serves as a voluntary greenhouse 
gas (GHG) registry to protect and promote early actions to reduce GHG 
emissions. The California Registry develops reporting standards and 
tools for organizations to measure, monitor, third party verify, and 
reduce their GHG emissions consistently across industry sectors and 
geographical borders. For more information about the California 
Registry, see [hyperlink, http://www.climateregistry.org/]. 

Standard: The Carbon Neutral Protocol; 
Description: The CarbonNeutral Protocol, a proprietary standard 
developed by The CarbonNeutral Company, describes the requirements for 
achieving "CarbonNeutral" status and the controls employed by The 
CarbonNeutral Company to ensure the correct use of CarbonNeutral logos. 
The protocol sets out the quality requirements for projects and schemes 
that produce offset credits that may be applied to make activities or 
entities CarbonNeutral under this program. For more information about 
the Carbon Neutral Protocol, see 
http://www.carbonneutral.com/pages/cnprotocol.asp]. 

Standard: Chicago Climate Exchange; 
Description: CCX is a voluntary greenhouse gas reduction and trading 
system through which members make commitments to decrease their 
emissions. CCX participants may trade offsets generated from qualifying 
emissions reduction projects. CCX employs a central registry for 
recording emissions as well as holdings and transfers of its serialized 
emission units-Carbon Financial Instruments (CFI). The registry is 
linked with the CCX electronic trading platform. For more information 
about CCX, see [hyperlink, http://www.chicagoclimatex.com/index.jsf]. 

Standard: Clean Development Mechanism; 
Description: The Clean Development Mechanism (CDM) is part of the Kyoto 
Protocol to the United Nations Framework Convention on Climate Change 
(UNFCCC). CDM enables industrialized countries to achieve emissions 
reductions by paying developing countries for certified emission 
reduction credits. CDM projects must qualify through a registration and 
issuance process. The mechanism is overseen by the CDM Executive Board, 
answerable ultimately to the countries that have ratified the Kyoto 
Protocol. For more information about CDM, see [hyperlink, 
http://cdm.unfccc.int/index.html]. 

Standard: Climate, Community, and Biodiversity Alliance; 
Description: The Climate, Community, and Biodiversity Alliance (CCBA) 
is a partnership among companies, nongovernmental organizations, and 
research institutes seeking to promote integrated solutions to land 
management around the world. CCB standards are project design standards 
for evaluating land-based carbon mitigation projects in the early 
stages of development. For more information about the CCB standards, 
see [hyperlink, http://www.climate-standards.org/]. 

Standard: Climate Leaders; 
Description: Climate Leaders is an EPA industry-government partnership 
that works with companies to develop climate change strategies. EPA 
Climate Leaders, a voluntary emissions reduction program, provides 
technical assistance to companies on how to calculate and track 
greenhouse gas emissions over time, calculate emissions reductions from 
offsets, and incorporate offsets into emission reduction strategies. 
EPA has developed accounting methodologies for certain offset project 
types including landfill gas, manure management, afforestation, 
transportation, and boiler replacement projects. Project protocols are 
being developed for additional project types, including coal-bed 
methane, methane end use from landfill and manure management projects, 
and forest management. For more information about Climate Leaders 
offset methodologies, see [hyperlink, 
http://www.epa.gov/climateleaders/resources/optional-module.html]. 

Standard: Climate Neutral Network; 
Description: The Climate Neutral Network is an alliance of companies 
and organizations committed to developing products, services, and 
enterprises that have a net-zero impact on global warming. The Climate 
Neutral Network certifies companies whose products, services, and/or 
enterprises have a net-zero impact on global warming. The Climate 
Neutral Network is closing as a nonprofit and transferring its 
certification program to another nonprofit. For more information about 
the Climate Neutral Network, see [hyperlink, 
http://climateneutralnetwork.org/]. 

Standard: Gold Standard Voluntary Emissions Reduction (VER); 
Description: The Gold Standard offers a quality label to voluntary 
offset projects for renewable energy and energy efficiency projects 
with sustainable development benefits for the local community. Gold 
Standard projects are tested for environmental quality by third parties 
and the Gold Standard carbon credit label is granted after third party 
validation and verification of the offset project. For more information 
about the Gold Standard VER, see [hyperlink, 
http://www.cdmgoldstandard.org/index.php]. 

Standard: United Kingdom Department for Environment, Food and Rural 
Affairs Code of Best Practice for Carbon Offsetting; 
Description: On February 19, 2008, the United Kingdom Department for 
Environment, Food and Rural Affairs (DEFRA) announced the framework for 
the Code of Best Practice for Carbon Offsetting to provide consumers 
with guidance on carbon offsets. Offset products meeting the 
requirements of the code will be assigned a certification mark that 
providers may use on their Web sites and other materials. The code is 
voluntary, and offset providers can choose whether to seek 
accreditation for all, or some, of their offsetting products. For more 
information about the DEFRA Code of Best Practice for Carbon Offsetting 
see [hyperlink, 
http://www.defra.gov.uk/environment/climatechange/uk/carbonoffset/index.
htm]. 

Standard: Green-e Climate; 
Description: Green-e Climate is a certification program for carbon 
offsets sold to consumers on the retail market. Green-e Climate sets 
consumer protection and environmental integrity standards and employs a 
three-step verification and certification service that ensures supply 
equals sales, offsets are independently certified, and consumer 
disclosures are accurate and follow program guidelines. For more 
information about Green-e Climate, see [hyperlink, http://www.green-
e.org/getcert_ghg.shtml]. 

Standard: Greenhouse Friendly™; 
Description: Greenhouse Friendly is an Australian government initiative 
aimed at providing businesses and consumers with the opportunity to 
sell and purchase greenhouse neutral products and services. For more 
information about Greenhouse Friendly, see [hyperlink, 
http://www.greenhouse.gov.au/greenhousefriendly/index.html]. 

Standard: ISO 14064; 
Description: ISO 14064 is a three-part international standard that 
provides guidance on developing organization-level emissions 
inventories; quantifying, monitoring, and reporting greenhouse gas 
emissions reductions at the project level; and validating and verifying 
greenhouse gas emissions reduction projects. More information about ISO 
14064 standards is available at [hyperlink, 
http://www.iso.org/iso/home.htm]. 

Standard: Plan Vivo; 
Description: Plan Vivo is a system for managing the supply of 
verifiable emission reductions from rural communities in a way that 
promotes sustainable livelihoods. Companies, individuals, or 
institutions wishing to offset greenhouse gas emissions can purchase 
voluntary emission reductions via a project trust fund in the form of 
Plan Vivo Certificates. Projects use the Plan Vivo management system to 
register and monitor carbon sequestration activities implemented by 
farmers. For more information about Plan Vivo, see [hyperlink, 
http://www.planvivo.org/]. 

Standard: Social Carbon; 
Description: Social Carbon has the objective of guaranteeing that the 
projects developed for the reduction of greenhouse gas emissions 
significantly contribute to sustainable development, incorporating 
transparent methods of access and measurement of the benefits that are 
returned to the parties involved and to the environment. The aim of the 
Social Carbon methodology is to provide offsets that also provide clear 
social and environmental benefits in the areas where projects operate. 
For more information about the Social Carbon methodology, see 
[hyperlink, http://www.socialcarbon.com/]. 

Standard: VER+; 
Description: The VER+ Standard provides a global standard for voluntary 
greenhouse gas emission reduction projects. The criteria of the VER+ 
Standard are streamlined with those of CDM, including the requirements 
of project additionality and corresponding tests that prove the project 
is not a business-as-usual scenario. For more information about the 
VER+ standard, see [hyperlink, 
https://www.netinform.de/KE/Beratung/Service_Ver.aspx]. 

Standard: Voluntary Carbon Standard; 
Description: The Voluntary Carbon Standard (VCS) was initiated by The 
Climate Group, the International Emissions Trading Association, and the 
World Economic Forum in late 2005 to standardize and provide 
transparency and credibility to the voluntary offset market, among 
other objectives. To recognize credible work that has gone into 
developing greenhouse gas programs around the world, the VCS Program 
has a process for recognizing programs that meet VCS criteria. For more 
information about the VCS, see [hyperlink, http://www.v-c-
s.org/index.html]. 

Standard: Voluntary Offset Standard; 
Description: The International Carbon Investors and Services (INCIS) 
Voluntary Offset Standard (VOS) can be used as a minimum standard when 
purchasing verified emission reduction credits on behalf of 
organizations or individuals offsetting their greenhouse gas emissions. 
The Voluntary Offset Standard is intended to support the development of 
emerging carbon markets around the world, and support international 
policy convergence with a view to long-term carbon market integration. 
For more information about the VOS, see [hyperlink, 
http://www.carboninvestors.org/documents]. 

Standard: Greenhouse Gas Protocol; 
Description: The Greenhouse Gas Protocol, a partnership between the 
World Resources Institute and the World Business Council for 
Sustainable Development, provides an accounting framework for 
greenhouse gas standards, programs, and inventories around the world. 
For more information about the Greenhouse Gas Protocol, see [hyperlink, 
http://www.ghgprotocol.org/]. 

Source: GAO analysis of offset standards cited by stakeholders and 
available market studies. 

Notes: Registries for tracking the distribution of offsets are not 
included in this table. Certain standards require the use of specific 
registries. 

This table summarizes and introduces the variety of standards available 
in the voluntary offset market. It is not an exhaustive list of 
standards, nor is it intended to provide precise descriptions. 

We do not summarize or compare the criteria of these standards because 
they exist for different purposes and apply to different portions of 
the carbon offset supply chain. For more specific information, please 
see standard documentation available at the referenced Web sites, if 
available. 

[End of table] 

[End of section] 

Appendix VIII: GAO Contact and Staff Acknowledgments: 

GAO Contact: 

John B. Stephenson, (202) 512-3841 or stephensonj@gao.gov: 

Staff Acknowledgments: 

In addition to the contact named above, Michael Hix, Assistant 
Director; Janice Ceperich; Nancy Crothers; Cindy Gilbert; Richard 
Johnson; Ben Shouse; Ardith A. Spence; and Joseph Thompson made major 
contributions to this report. Richard Burkard, Terrell G. Dorn, Steve 
Gaty, Jim McDermott, Andy O'Connell, Dan Packa, Kate Robertson, Ray 
Rodriguez, Jena Sinkfield, and Sara Vermillion also made important 
contributions. 

[End of section] 

Footnotes: 

[1] Major greenhouse gases include carbon dioxide (CO2), methane (CH4), 
nitrous oxide (N2O), and synthetic gases: hydrofluorocarbons (HFCs), 
perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). 

[2] Carbon offsets are typically quantified and described in terms of 
metric tons of carbon dioxide equivalent. A metric ton equals 2,205 
pounds, while a short ton, a measurement used in the United States, 
equals 2,000 pounds. Unless otherwise specified, this report uses 
metric tons. Carbon dioxide equivalents provide a common standard for 
measuring the warming potential of different greenhouse gases and are 
calculated by multiplying the emissions of the non-carbon dioxide gas 
by its global warming potential, a factor that measures its heat- 
trapping ability relative to that of carbon dioxide. 

[3] In 2006, carbon dioxide released from the burning of fossil fuels 
accounted for approximately 78 percent of human-caused greenhouse gas 
emissions in the United States. The remaining 22 percent of emissions 
included carbon dioxide from nonenergy use of fossil fuels and iron and 
steel production; methane from landfills, coal mines, oil and gas 
operations, and agriculture; nitrous oxide from fossil fuels, 
fertilizers, and industrial processes; and other synthetic gases 
emitted from industrial sources, such as sulfur hexafluoride and 
perfluorocarbons, from the production of magnesium and aluminum. 

[4] The EU's program to limit greenhouse gas emissions enables 
regulated entities to use certain types of offsets, including Clean 
Development Mechanism (CDM) credits, for compliance. The CDM, 
administered by the United Nations, is part of the Kyoto Protocol. CDM 
enables industrialized countries to achieve emissions reductions by 
paying for certified emission reduction credits, each equivalent to one 
metric ton of carbon dioxide, from projects in developing countries. 
GAO is reviewing the European Union's program and the CDM in a report 
that we will issue later in 2008. 

[5] CCX defines "legally binding" to mean that members who undertake 
the reduction commitment sign a contract with CCX that requires them to 
abide by the CCX rulebook, submit their emissions data to a 
standardized data review by Financial Industry Regulatory Authority 
(FINRA), and be subject to the various governance committees of CCX for 
a stipulated and fixed period of membership. CCX Phase I required 
compliance from 2003 to 2006 and Phase II from 2007 to 2010. 

[6] The term "retirement" refers to the permanent recorded disposition 
of an offset after which it cannot be resold or otherwise used by any 
entity to facilitate, enable, or offset any past, present, or future 
greenhouse gas emission. 

[7] Nonprobability samples cannot be used to generalize or make 
inferences about a population. In this instance, we cannot generalize 
the results of our interviews to all carbon offset market participants. 

[8] These data represent a conservative estimate of supply because 
Point Carbon estimates that its database accounts for approximately 80 
percent of the offsets generated from projects located in the United 
States based on its analysis of domestic and global carbon markets. 

[9] Katherine Hamilton, Milo Sjardin, Thomas Marcello, and Gordon Xu, 
Forging a Frontier: State of the Voluntary Carbon Markets 2008 
(Ecosystem Marketplace and New Carbon Finance: May 2008). This report 
said that the $306 per ton price resulted from one particularly high 
transaction. The sponsors of Ecosystem Marketplace include, among 
others, organizations that facilitate projects to reduce, avoid, or 
sequester greenhouse gas emissions. Prices are reported in 2008 U.S. 
dollars. 

[10] See [hyperlink, 
http://www.chicagoclimatex.com/market/data/summary.jsf] for CCX market 
information. Prices are reported in 2008 U.S. dollars. 

[11] Hamilton, Sjardin, Marcello, and Xu, Forging a Frontier. Prices 
are reported in 2008 U.S. dollars. 

[12] Hamilton, Sjardin, Marcello, and Xu, Forging a Frontier. 

[13] GAO analysis of Point Carbon data. 

[14] GAO analysis of Point Carbon data. 

[15] See the Fourth Assessment Report of the Intergovernmental Panel on 
Climate Change. 

[16] GAO analysis of Point Carbon data. 

[17] According to CFTC officials, exempt commodities include emissions 
allowances. 

[18] Price discovery refers to the process by which market prices 
incorporate new information. 

[19] FTC, Guides for the Use of Environmental Marketing Claims 16 
C.F.R. Part 260. 

[20] Hamilton, Sjardin, Marcello, and Xu, Forging a Frontier. 

[21] Anja Kollmuss, Helge Zink, and Clifford Polycarp, Making Sense of 
the Voluntary Carbon Market: A Comparison of Carbon Offset Standards 
(Stockholm Environment Institute and Tricorona: March 2008). 

[22] Hamilton, Sjardin, Marcello, and Xu, Forging a Frontier. 

[23] Stakeholders who responded to our questions also identified the 
concept of "leakage"--the possibility that emissions increase elsewhere 
as a result of the implementation of a carbon offset project--as a 
challenge, which we address later in this report. 

[24] Renewable energy certificates certify that a certain quantity of 
electricity has been generated from a qualifying type of renewable 
generation technology. 

[25] See EPA Analysis of the Lieberman-Warner Climate Security Act of 
2008, S.2191 in the 110th Congress (March 2008), available at 
[hyperlink, 
http://www.epa.gov/climatechange/economics/economicanalyses.html]. 

[26] See EPA Analysis of the Climate Stewardship and Innovation Act of 
2007, S.280 in the 110th Congress, (July 2007), available at 
[hyperlink, 
http://www.epa.gov/climatechange/economics/economicanalyses.html]. 

[27] See EIA analysis of the Climate Stewardship and Innovation Act of 
2007, S.280 in the 110th Congress (July 2007), available at [hyperlink, 
http://www.eia.doe.gov/oiaf/servicerpt/csia/]. See also Congressional 
Research Service Report for Congress, Climate Change: Costs and 
Benefits of S.2191, which analyzes the role of offsets in six different 
quantitative economic models of the Lieberman-Warner Climate Security 
Act of 2008, S.2191 in the 110th Congress (July 2008). 

[28] EPA analyses and other economic literature generally evaluate cap- 
and-trade compliance systems as opposed to other policy options. 

[29] See Judson Jaffe and Robert Stavins. "Linking a U.S. Cap-and-Trade 
System for Greenhouse Gas Emissions: Opportunities, Implications, and 
Challenges." American Enterprise Institute Center for Regulatory and 
Market Studies, Working Paper 08-01 (January 2008). 

[30] See Jaffe and Stavins (2008), and Joseph Kruger, Wallace E. Oates, 
and William A. Pizer. "Decentralization in the EU Emissions Trading 
Scheme and Lessons for Global Policy." Review of Environmental 
Economics and Policy, Vol. 1, Iss. 1 (winter 2007). 

[31] For example, see Jaffe and Stavins (2008), and Kruger, Oates, and 
Pizer (2007). See also Carolyn Fischer. "Project Based Mechanisms for 
Emissions Reductions: Balancing Trade-offs with Baselines," RFF DP 04- 
32, Resources for the Future (August 2004). 

[32] A recent report by the Congressional Research Service discusses 
the potential and drawbacks of incorporating forestry projects into 
carbon markets. See Forest Carbon Markets: Potential and Drawbacks, 
RL34560 (Washington, D.C.: July 3, 2008). Other related Congressional 
Research Service reports include Voluntary Carbon Offsets: Overview and 
Assessment, RL34241 (Washington, D.C.: Nov. 7, 2007), and The Role of 
Offsets in a Greenhouse Gas Emissions Cap-and-Trade Program: Potential 
Benefits and Concerns, RL34436 (Washington, D.C.: Apr. 4, 2008). 

[33] Nonprobability samples cannot be used to generalize or make 
inferences about a population. In this instance, we cannot generalize 
the results of our interviews to all carbon offset market participants. 

[34] The Green the Capitol Initiative report presents data in English 
short tons. One short ton equals 2,000 pounds. 

[35] Carbon Financial Instruments are contracts equal to 100 metric 
tons of carbon dioxide equivalent that are traded on the Chicago 
Climate Exchange. 

[36] The Financial Industry Regulatory Authority is the largest 
nongovernmental regulator for all securities firms doing business in 
the United States. It was created in July 2007 through the 
consolidation of the National Association of Securities Dealers (NASD) 
and the member regulation, enforcement, and arbitration functions of 
the New York Stock Exchange. FINRA's predecessor was established 
pursuant to the Maloney Act, which was passed by Congress in 1938. 

[37] See H.R. Rep. No. 110-198 at 10 (2007). 

[38] GAO, Legislative Branch: Energy Audits Are Key to Strategy for 
Reducing Greenhouse Gas Emissions, GAO-07-516 (Washington, D.C.: Apr. 
25, 2007). GAO's analysis identified the amount of greenhouse gas 
emissions generated by legislative branch operations. 

[39] A metric ton is equivalent to 2,205 pounds and a short ton equals 
2,000 pounds. 

[40] The price per metric ton of carbon traded on CCX has increased 
since the CAO purchase. For example, in June 2008, the market closing 
price of CFIs reached $7.40 per metric ton. 

[41] The CAO and CCX said that the cost of 30,000 metric tons purchased 
in November was below the cost projected for 24,000 metric tons and 
also below the cost estimated for the purchase of 24,000 metric tons at 
the time of passage of the relevant appropriations bill. 

[42] The term "retirement" refers to the permanent recorded disposition 
of an offset after which it cannot be resold or otherwise utilized by 
any entity to facilitate, enable, or offset any past, present, or 
future greenhouse gas emission. 

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