16-i 

CHAPTER 16. MONETIZATION OF EMISSION REDUCTIONS BENEFITS 

TABLE OF CONTENTS

16.1 INTRODUCTION ......................................................................................................... 16-1

16.2 MONETIZING CARBON DIOXIDE EMISSIONS ..................................................... 16-1

16.2.1 Social Cost of Carbon .................................................................................................... 16-1

16.2.2 Social Cost of Carbon Values Used in Past Regulatory Analyses ................................. 16-1

16.2.3 Current Approach and Key Assumptions ...................................................................... 16-3

16.3 VALUATION OF OTHER EMISSIONS REDUCTIONS ........................................... 16-6

16.4 RESULTS ...................................................................................................................... 16-6

LIST OF TABLES

Table 16-1 Social Cost of CO2, 2010 – 2050 (in 2007 dollars per metric ton) ......................... 16-5

Table 16-2 Clothes Dryers: Estimates of Global Present Value of CO2 Emissions 

Reduction in 2014–2043 Under Trial Standard Levels ..................................... 16-7

Table 16-3 Room Air Conditioners: Estimates of Global Present Value of CO2 Emissions 

Reduction in 2014–2043 Under Trial Standard Levels ..................................... 16-7

Table 16-4 Clothes Dryers: Estimates of Domestic Present Value of CO2 Emissions 

Reduction in 2014–2043 Under Trial Standard Levels ..................................... 16-8

Table 16-5 Room Air Conditioners: Estimates of Domestic Present Value of CO2

Emissions Reduction in 2014–2043 Under Trial Standard Levels .................... 16-8

Table 16-6 Clothes Dryers: Estimates of Present Value of NOX Emissions Reduction in 

2014-2043 Under Trial Standard Levels ............................................................ 16-9

Table 16-7 Room Air Conditioners: Estimates of Present Value of NOX Emissions 

Reduction in 2014-2043 Under Trial Standard Levels ...................................... 16-9
16-1 

CHAPTER 16. MONETIZATION OF EMISSION REDUCTIONS BENEFITS 

16.1 INTRODUCTION

As part of its assessment of energy conservation standards, DOE considered the estimated 

monetary benefits likely to result from the reduced emissions of carbon dioxide (CO2) and 

nitrogen oxides (NOX) that are expected to result from each of the TSLs considered. In order to 

make this calculation similar to the calculation of the NPV of consumer benefit, DOE considered 

the reduced emissions expected to result over the lifetime of products shipped in the forecast 

period for each TSL. This chapter summarizes the basis for the monetary values used for each of 

these emissions and presents the benefits estimates considered. 

16.2 MONETIZING CARBON DIOXIDE EMISSIONS

16.2.1 Social Cost of Carbon 

 Under section 1(b) of Executive Order 12866, “Regulatory Planning and Review,” 58 FR 

51735 (Oct. 4, 1993), agencies must, to the extent permitted by law, “assess both the costs and 

the benefits of the intended regulation and, recognizing that some costs and benefits are difficult 

to quantify, propose or adopt a regulation only upon a reasoned determination that the benefits of 

the intended regulation justify its costs.” 

 The purpose of the social cost of carbon (SCC) estimates presented here is to allow 

Federal agencies to incorporate the monetized social benefits of reducing CO2 emissions into 

cost-benefit analyses of regulatory actions that have small, or “marginal,” impacts on cumulative 

global emissions. The estimates are presented with an acknowledgement of the many 

uncertainties involved and with a clear understanding that they should be updated over time to 

reflect increasing knowledge of the science and economics of climate impacts.

As part of the interagency process that developed these SCC estimates, technical experts 

from numerous agencies met on a regular basis to consider public comments, explore the 

technical literature in relevant fields, and discuss key model inputs and assumptions. The main 

objective of this process was to develop a range of SCC values using a defensible set of input 

assumptions grounded in the existing scientific and economic literatures. In this way, key 

uncertainties and model differences transparently and consistently inform the range of SCC 

estimates used in the rulemaking process.

The social cost of carbon is an estimate of the monetized damages associated with an 

incremental increase in carbon emissions in a given year. It is intended to include (but is not 

limited to) changes in net agricultural productivity, human health, property damages from 

increased flood risk, and the value of ecosystem services. Estimates of the SCC are provided in 

dollars per metric ton of carbon dioxide. 
16-2 

 When attempting to assess the incremental economic impacts of carbon dioxide 

emissions, the analyst faces a number of serious challenges. A recent report from the National 

Research Councila

 points out that any assessment will suffer from uncertainty, speculation, and 

lack of information about (1) future emissions of greenhouse gases, (2) the effects of past and 

future emissions on the climate system, (3) the impact of changes in climate on the physical and 

biological environment, and (4) the translation of these environmental impacts into economic 

damages. As a result, any effort to quantify and monetize the harms associated with climate 

change will raise serious questions of science, economics, and ethics and should be viewed as 

provisional. 

Despite the serious limits of both quantification and monetization, SCC estimates can be 

useful in estimating the social benefits of reducing carbon dioxide emissions. Consistent with the 

directive quoted above, the purpose of the SCC estimates presented here is to make it possible 

for agencies to incorporate the social benefits from reducing carbon dioxide emissions into costbenefit analyses of regulatory actions that have small, or “marginal,” impacts on cumulative 

global emissions. Most Federal regulatory actions can be expected to have marginal impacts on 

global emissions.

For such policies, the agency can estimate the benefits from reduced (or costs from 

increased) emissions in any future year by multiplying the change in emissions in that year by 

the SCC value appropriate for that year. The net present value of the benefits can then be 

calculated by multiplying each of these future benefits by an appropriate discount factor and 

summing across all affected years. This approach assumes that the marginal damages from 

increased emissions are constant for small departures from the baseline emissions path, an 

approximation that is reasonable for policies that have effects on emissions that are small relative 

to cumulative global carbon dioxide emissions. For policies that have a large (non-marginal) 

impact on global cumulative emissions, there is a separate question of whether the SCC is an 

appropriate tool for calculating the benefits of reduced emissions. DOE does not attempt to 

answer that question here. 

It is important to emphasize that the interagency process is committed to updating these 

estimates as the science and economic understanding of climate change and its impacts on 

society improves over time. Specifically, the interagency group has set a preliminary goal of 

revisiting the SCC values within two years or at such time as substantially updated models 

become available, and to continue to support research in this area. In the meantime, the 

interagency group will continue to explore the issues raised by this analysis and consider public 

comments as part of the ongoing interagency process. 

16.2.2 Social Cost of Carbon Values Used in Past Regulatory Analyses 

 To date, economic analyses for Federal regulations have used a wide range of values to 

estimate the benefits associated with reducing carbon dioxide emissions. In the final model year 

2011 CAFE rule, the Department of Transportation (DOT) used both a “domestic” SCC value of 

 

a National Research Council. Hidden Costs of Energy: Unpriced Consequences of Energy Production and Use. 

National Academies Press: Washington, DC. 2009. 
16-3 

$2 per ton of CO2 and a “global” SCC value of $33 per ton of CO2 for 2007 emission reductions 

(in 2007 dollars), increasing both values at 2.4 percent per year.b It also included a sensitivity 

analysis at $80 per ton of CO2. A domestic SCC value is meant to reflect the value of damages 

in the United States resulting from a unit change in carbon dioxide emissions, while a global 

SCC value is meant to reflect the value of damages worldwide.

 A 2008 regulation proposed by DOT assumed a domestic SCC value of $7 per ton of CO2

(in 2006 dollars) for 2011 emission reductions (with a range of $0-$14 for sensitivity analysis), 

also increasing at 2.4 percent per year.c

 A regulation for packaged terminal air conditioners and 

packaged terminal heat pumps finalized by DOE in October 2008 used a domestic SCC range of 

$0 to $20 per ton CO2 for 2007 emission reductions (in 2007 dollars). 73 FR 58772, 58814 (Oct. 

7, 2008) In addition, EPA’s 2008 Advance Notice of Proposed Rulemaking for Greenhouse 

Gases identified what it described as “very preliminary” SCC estimates subject to revision.d

EPA’s global mean values were $68 and $40 per ton CO2 for discount rates of approximately 2 

percent and 3 percent, respectively (in 2006 dollars for 2007 emissions). 

 In 2009, an interagency process was initiated to offer a preliminary assessment of how 

best to quantify the benefits from reducing carbon dioxide emissions. To ensure consistency in 

how benefits are evaluated across agencies, the Administration sought to develop a transparent 

and defensible method, specifically designed for the rulemaking process, to quantify avoided 

climate change damages from reduced CO2 emissions. The interagency group did not undertake 

any original analysis. Instead, it combined SCC estimates from the existing literature to use as 

interim values until a more comprehensive analysis could be conducted. The outcome of the 

preliminary assessment by the interagency group was a set of five interim values: global SCC 

estimates for 2007 (in 2006 dollars) of $55, $33, $19, $10, and $5 per ton of CO2. 

 These interim values represent the first sustained interagency effort within the U.S. 

government to develop an SCC for use in regulatory analysis. The results of this preliminary 

effort were presented in several proposed and final rules and were offered for public comment in 

connection with proposed rules, including the joint EPA-DOT fuel economy and CO2 tailpipe 

emission proposed rules. See CAFE Rule for Passenger Cars and Light Trucks Draft EIS and 

Final EIS, cited above.

16.2.3 Current Approach and Key Assumptions

 Since the release of the interim values, the interagency group reconvened on a regular 

basis to generate improved SCC estimates, which were considered for this proposed rule. 

Specifically, the group considered public comments and further explored the technical literature 

in relevant fields. The interagency group relied on three integrated assessment models (IAMs) 

 

b See Average Fuel Economy Standards Passenger Cars and Light Trucks Model Year 2011, 74 FR 14196 (March 

30, 2009); Final Environmental Impact Statement Corporate Average Fuel Economy Standards, Passenger Cars and 

Light Trucks, Model Years 2011-2015 at 3-90 (Oct. 2008) (Available at: http://www.nhtsa.gov/fuel-economy). c See Average Fuel Economy Standards, Passenger Cars and Light Trucks, Model Years 2011-2015, 73 FR 24352 

(May 2, 2008); Draft Environmental Impact Statement Corporate Average Fuel Economy Standards, Passenger Cars 

and Light Trucks, Model Years 2011-2015 at 3-58 (June 2008) (Available at: http://www.nhtsa.gov/fuel-economy). d See Regulating Greenhouse Gas Emissions Under the Clean Air Act, 73 FR 44354 (July 30, 2008).
16-4 

commonly used to estimate the SCC: the FUND, DICE, and PAGE models.e These models are 

frequently cited in the peer-reviewed literature and were used in the last assessment of the 

Intergovernmental Panel on Climate Change. Each model was given equal weight in the SCC 

values that were developed. 

Each model takes a slightly different approach to model how changes in emissions result 

in changes in economic damages. A key objective of the interagency process was to enable a 

consistent exploration of the three models while respecting the different approaches to 

quantifying damages taken by the key modelers in the field. An extensive review of the literature 

was conducted to select three sets of input parameters for these models: (1) climate sensitivity; 

(2) socio-economic and emissions trajectories; and (3) discount rates. A probability distribution 

for climate sensitivity was specified as an input into all three models. In addition, the interagency 

group used a range of scenarios for the socio-economic parameters and a range of values for the 

discount rate. All other model features were left unchanged, relying on the model developers’ 

best estimates and judgments.

 The interagency group selected four SCC values for use in regulatory analyses. Three 

values are based on the average SCC from three integrated assessment models, at discount rates 

of 2.5, 3, and 5 percent. The fourth value, which represents the 95th percentile SCC estimate 

across all three models at a 3 percent discount rate, is included to represent higher-than-expected 

impacts from temperature change further out in the tails of the SCC distribution. For emissions 

(or emission reductions) that occur in later years, these values grow in real terms over time, as 

depicted in Table 16-1. Additionally, the interagency group determined that a range of values 

from 7 percent to 23 percent should be used to adjust the global SCC to calculate domestic 

effects,f

 although preference is given to consideration of the global benefits of reducing CO2

emissions.

 

e The models are described in appendix 16-A of the TSD. f It is recognized that this calculation for domestic values is approximate, provisional, and highly speculative. There 

is no a priori reason why domestic benefits should be a constant fraction of net global damages over time.
16-5 

Table 16-1 Social Cost of CO2, 2010 – 2050 (in 2007 dollars per metric ton) 

Discount Rate 

5% 3% 2.5% 3%

Avg Avg Avg 95th

2010 4.7 21.4 35.1 64.9 

2015 5.7 23.8 38.4 72.8

2020 6.8 26.3 41.7 80.7

2025 8.2 29.6 45.9 90.4

2030 9.7 32.8 50.0 100.0

2035 11.2 36.0 54.2 109.7

2040 12.7 39.2 58.4 119.3

2045 14.2 42.1 61.7 127.8

2050 15.7 44.9 65.0 136.2

 It is important to recognize that a number of key uncertainties remain, and that current 

SCC estimates should be treated as provisional and revisable since they will evolve with 

improved scientific and economic understanding. The interagency group also recognizes that the 

existing models are imperfect and incomplete. The National Research Council report mentioned 

above points out that there is tension between the goal of producing quantified estimates of the 

economic damages from an incremental ton of carbon and the limits of existing efforts to model 

these effects. There are a number of concerns and problems that should be addressed by the 

research community, including research programs housed in many of the agencies participating 

in the interagency process to estimate the SCC.

 The U.S. Government intends to periodically review and reconsider estimates of the SCC 

used for cost-benefit analyses to reflect increasing knowledge of the science and economics of 

climate impacts, as well as improvements in modeling. In this context, statements recognizing 

the limitations of the analysis and calling for further research take on exceptional significance. 

The interagency group offers the new SCC values with all due humility about the uncertainties 

embedded in them and with a sincere promise to continue work to improve them. 

In summary, in considering the potential global benefits resulting from reduced CO2

emissions, DOE used the most recent SCC values identified by the interagency process, adjusted 

to 2009$ using the GDP price deflator values for 2008 and 2009. For each of the four cases 

specified, the values used for emissions in 2010 were $4.9, $22.1, $36.3, and $67.1 per metric 

ton avoided (values expressed in 2009$). To monetize the CO2 emissions reductions expected to 

result from amended standards for clothes dryers and room air conditioners, DOE used the 

values identified in Table A1 of the “Social Cost of Carbon for Regulatory Impact Analysis 

Under Executive Order 12866,” which is reprinted in appendix 16-A of this TSD, appropriately 

escalated to 2009$.g

 

g Table A1 presents SCC values through 2050. For DOE’s calculation, it derived values after 2050 using the 3-

percent per year escalation rate used by the interagency group.

To calculate a present value of the stream of monetary values, DOE 
16-6 

discounted the values in each of the four cases using the specific discount rate that had been used 

to obtain the SCC values in each case.

16.3 VALUATION OF OTHER EMISSIONS REDUCTIONS

DOE considered the potential monetary benefit of reduced NOX emissions from the TSLs 

it considered. As noted in chapter 15, new or amended energy conservation standards would 

reduce NOX emissions in those 22 States that are not affected by the CAIR, in addition to the 

reduction in site NOX emissions nationwide. DOE estimated the monetized value of NOX

emissions reductions resulting from each of the TSLs considered based on environmental 

damage estimates from the literature. Available estimates suggest a very wide range of monetary 

values, ranging from $370 per ton to $3,800 per ton of NOX from stationary sources, measured in 

2001$ (equivalent to a range of $447 to $4,591 per ton in 2009$).h In accordance with OMB 

guidance, DOE conducted two calculations of the monetary benefits using each of the above 

values used for NOX, one using a real discount rate of 3 percent and another using a real discount 

rate of 7 percent. i

 

DOE is aware of multiple agency efforts to determine the appropriate range of values used 

in evaluating the potential economic benefits of reduced Hg emissions. DOE has decided to 

await further guidance regarding consistent valuation and reporting of Hg emissions before it 

once again monetizes Hg in its rulemakings. 

16.4 RESULTS

Table 16-2 and Table 16-3 present the global values of CO2 emissions reductions for each 

TSL. DOE calculated domestic values as a range from 7 percent to 23 percent of the global 

values, and these results are presented in Table 16-4 and Table 16-5. 

 

h

 For additional information, refer to U.S. Office of Management and Budget, Office of Information and Regulatory 

Affairs, ‘‘2006 Report to Congress on the Costs and Benefits of Federal Regulations and Unfunded Mandates on 

State, Local, and Tribal Entities,’’ Washington, DC. i

 OMB, Circular A-4: Regulatory Analysis (Sept. 17, 2003).
16-7 

Table 16-2 Clothes Dryers: Estimates of Global Present Value of CO2 Emissions Reduction 

in 2014–2043 Under Trial Standard Levels 

TSL

Million 2009$

5% discount 

rate, 

average*

3% discount 

rate, 

average*

2.5% discount 

rate, average*

3% discount 

rate, 95th

percentile*

1 2 13 21 38

2 30 151 255 460

3 84 424 716 1,293

4 107 541 913 1,650

5 292 1,471 2,483 4,487

6 719 3,599 6,066 10,979

* Columns are labeled by the discount rate used to calculate the SCC and whether it is an average value or drawn 

from a different part of the distribution. Values presented incorporate the escalation of the SCC over time.

Table 16-3 Room Air Conditioners: Estimates of Global Present Value of CO2 Emissions 

Reduction in 2014–2043 Under Trial Standard Levels

TSL

5% discount 

rate, 

average*

Million 2009$

3% discount 

rate, 

average*

2.5% discount 

rate, average*

3% discount 

rate, 95th

percentile*

1 36 177 298 542

2 45 225 378 686

3 45 220 370 673

4 64 318 535 972

5 102 506 852 1,546

6 138 683 1,150 2,086

* Columns are labeled by the discount rate used to calculate the SCC and whether it is an average value or drawn 

from a different part of the distribution. Values presented incorporate the escalation of the SCC over time.
16-8 

Table 16-4 Clothes Dryers: Estimates of Domestic Present Value of CO2 Emissions 

Reduction in 2014–2043 Under Trial Standard Levels 

TSL

Million 2009$

5% discount 

rate, average**

*

3% discount 

rate, average**

2.5% discount 

rate, average**

3% discount rate, 

95th percentile**

1 0.175 to 0.575 0.881 to 2.90 1.49 to 4.89 2.69 to 8.83

2 2.09 to 6.88 10.6 to 34.7 17.8 to 58.6 32.2 to 106

3 5.88 to 19.3 29.7 to 97.5 50.1 to 165 90.5 to 297

4 7.52 to 24.7 37.9 to 124 63.9 to 210 116 to 380

5 20.4 to 67.2 103 to 338 174 to 571 314 to 1,032

6 50.3 to 165 252 to 828 425 to 1,395 768 to 2,525

* Domestic values are calculated as a range between 7% and 23% of the global values.

** Columns are labeled by the discount rate used to calculate the SCC and whether it is an average value or drawn 

from a different part of the distribution. Values presented incorporate the escalation of the SCC over time.

Table 16-5 Room Air Conditioners: Estimates of Domestic Present Value of CO2 Emissions 

Reduction in 2014–2043 Under Trial Standard Levels 

TSL

Million 2009$

5% discount 

rate, average**

*

3% discount 

rate, average**

2.5% discount 

rate, average**

3% discount rate, 

95th percentile**

1 2.51 to 8.25 12.4 to 40.8 20.9 to 68.6 37.9 to 125

2 3.18 to 10.4 15.7 to 51.7 26.5 to 86.9 48.0 to 158

3 3.12 to 10.24 15.4 to 50.7 25.9 to 85.2 47.1 to 155

4 4.50 to 14.8 22.3 to 73.2 37.5 to 123 68.0 to 224

5 7.15 to 23.5 35.5 to 116 59.6 to 196 108 to 356

6 9.64 to 31.7 47.8 to 157 80.5 to 264 146 to 480

* Domestic values are calculated as a range between 7% and 23% of the global values.

** Columns are labeled by the discount rate used to calculate the SCC and whether it is an average value or drawn 

from a different part of the distribution. Values presented incorporate the escalation of the SCC over time.

Table 16-6 and Table 16-7 present the cumulative monetary value of the economic 

benefits associated with NOX emissions reductions for each TSL, calculated using seven-percent 

and three-percent discount rates.
16-9 

Table 16-6 Clothes Dryers: Estimates of Present Value of NOX Emissions Reduction in 

2014-2043 Under Trial Standard Levels 

TSL

3% discount rate 7% discount rate

Million 2009$

1

Million 2009$

0.124 to 1.27 0.051 to 0.523

2 1.47 to 15.1 0.597 to 6.14

3 4.14 to 42.5 1.67 to 17.2

4 5.3 to 54.7 2.20 to 22.6

5 14.5 to 149 6.01 to 61.8

6 36.8 to 378 16.7 to 172

Table 16-7 Room Air Conditioners: Estimates of Present Value of NOX Emissions 

Reduction in 2014-2043 Under Trial Standard Levels 

TSL

3% discount rate 7% discount rate

Million 2009$

1

Million 2009$

1.86 to 19.1 0.867 to 8.91

2 2.35 to 24.2 1.09 to 11.2

3 2.30 to 23.6 1.06 to 10.9

4 3.32 to 34.1 1.53 to 15.7

5 5.27 to 54.2 2.43 to 25.0

6 7.11 to 73.1 3.28 to 33.8