ENVIRONMENTAL ASSESSMENT FOR 

10 CFR 431 

ENERGY CONSERVATION PROGRAM FOR 

COMMERCIAL AND INDUSTRIAL EQUIPMENT: 

PACKAGED TERMINAL AIR CONDITIONER AND 

PACKAGED TERMINAL HEAT PUMP ENERGY 

CONSERVATION STANDARDS; FINAL RULE 

October 2008 

DOE/EA-1637 
NOTE: 

The following Environmental Assessment (DOE/EA-1637) was integrated into the 

Technical Support Document (TSD) that was prepared for the Final Rule, 10 CFR Part 

431, regarding the Department of Energy’s energy conservation standards rulemaking on 

packaged terminal air conditioners and packaged terminal heat pumps. The 

environmental analysis was contained in Chapter 16 of the TSD, which is provided here. 

The complete TSD is located on the Office of Energy Efficiency and Renewable 

Energy’s Website at the following URL: 

http://www1.eere.energy.gov/buildings/appliance_standards/commercial/ptacs_pthps_fi

nal_tsd.html.
CHAPTER 16. ENVIRONMENTAL IMPACT ANALYSIS 

TABLE OF CONTENTS 

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

16.2 AIR EMISSIONS ANALYSIS ............................................................................. 16-1

16.2.1 Air Emissions Descriptions.................................................................... 16-1

16.2.2 Air Quality Regulation ........................................................................... 16-3

16.2.3 Global Climate Change .......................................................................... 16-5

16.2.4 Analytical Methods for Air Emissions .................................................. 16-8

16.2.5 Effects on Power Plant Emissions ....................................................... 16-10

16.2.6 Effects on Upstream Fuel-Cycle Emissions ........................................ 16-15

16.2.7 Economic Valuation of Emissions Reductions .................................... 16-16

16.3 WETLAND, ENDANGERED AND THREATENED SPECIES, AND CULTURAL 

RESOURCES ..................................................................................................... 16-24

16.4 SOCIOECONOMIC IMPACTS ......................................................................... 16-24

16.5 ENVIRONMENTAL JUSTICE IMPACTS ....................................................... 16-25

16.6 NOISE AND AESTHETICS .............................................................................. 16-25

16.7 SUMMARY OF ENVIRONMENTAL IMPACTS ............................................ 16-25

LIST OF TABLES 

Table 16.2.1 Impact of the PTAC and PTHP Efficiency Standard on Cumulative EnergyRelated Emissions of CO2 Between 2012 and 2042 by Trial Standard Level 

(Millions of Metric Tons CO2) .............................................................. 16-8

Table 16.2.2 Emissions Forecast for AEO 2008 Reference Case ............................. 16-11

Table 16.2.3 Emissions Impact Forecasts for Standard Size PTACs ....................... 16-12

Table 16.2.4 Emissions Impact Forecasts for Non-Standard Size PTACs ............... 16-13

Table 16.2.5 Emissions Impact Forecasts for Standard Size PTHPs ........................ 16-14

Table 16.2.6 Emissions Impact Forecasts for Non-Standard Size PTHPs ................ 16-15

Table 16.2.7 Estimated Upstream Emissions of Air Pollutants as a Percentage of Direct 

Power Plant Combustion Emissions .................................................... 16-16

Table 16.2.8 Estimates of Savings from CO2 Emissions Reductions under PTAC and PTHP 

Trial Standard Levels at 7% Discount Rate and 3% Discount Rate .... 16-18

Table 16.2.9 Estimates of Savings from Reductions of NOx and Hg under PTAC and PTHP 

Trial Standard Levels at a 7% Discount Rate ...................................... 16-21

Table 16.2.10 Preliminary Estimates of Savings from Reductions of NOx and Hg under 

PTAC and PTHP Trial Standard Levels at a 3% Discount Rate ......... 16-21

Table 16.4.1 Mean Life-Cycle Cost Savings for All Customers and Sub-Group, Standard 

Size PTACs and PTHPs ....................................................................... 16-24

Table 16.7.1 Environmental Impact Analysis Results Summary, Standard-Size PTACs and 

PTHPs .................................................................................................. 16-26

Table 16.7.2 Environmental Impact Analysis Results Summary, Non-Standard PTACs and 

PTHPs .................................................................................................. 16-27

16-i
16-ii
CHAPTER 16. ENVIRONMENTAL IMPACT ANALYSIS 

16.1 INTRODUCTION 

This chapter describes potential environmental effects that may result from 

amended energy conservation standards for packaged terminal air conditioners (PTACs) 

and packaged terminal heat pumps (PTHPs). The U.S. Department of Energy (DOE)’s 

proposed energy conservation standards are not site-specific, and would apply to all 50 

States and U.S. territories. Therefore, none of the proposed standards would impact land 

uses, cause any direct disturbance to the land, or directly affect biological resources in 

any one area. 

All of the potential trial standard levels (TSLs) are expected to reduce energy 

consumption in comparison to a baseline efficiency level. These changes in the demand 

for electricity and the costs of achieving these savings are the primary drivers in 

analyzing environmental effects. Estimates of source energy savings can be found in the 

utility impact analysis in Chapter 14 of this technical support document (TSD). Detailed 

discussion on TSLs can be found in Chapter 9 of this TSD. 

The primary impact of the TSLs is in air quality resulting from changes in power 

plant operations and capacity additions. Therefore, much of this chapter describes the air 

quality analysis. The latter part of the chapter describes potential impacts to other 

environmental resources. 

16.2 AIR EMISSIONS ANALYSIS 

The primary focus of the environmental analysis is the impact on air quality of 

amended energy conservation standards for PTAC and PTHP equipment. The outcomes 

of the environmental analysis are driven by changes in power plant types and quantities 

of electricity generated under each of the alternatives. Changes in generation are 

described in the utility impact analysis in Chapter 14. 

16.2.1 Air Emissions Descriptions 

For each of the TSLs, DOE calculated total power-sector emissions based on 

output from NEMS-BT model (see Chapter 14). This analysis considers three pollutants: 

nitrogen oxides (NOx), mercury (Hg), and sulfur dioxide (SO2). An air pollutant is any 

substance in the air that can cause harm to humans or the environment. Pollutants may 

be natural or man-made (i.e., anthropogenic) and may take the form of solid particles 

(i.e., particulates or particulate matter), liquid droplets, or gasesa

. This analysis also 

considers carbon dioxide (CO2). 

 

a

 More information on air pollution characteristics and regulations is available on the U.S. Environment 

Protection Agent (EPA)’s website at www.epa.gov. 

16-1
Sulfur Dioxide (SO2) 

In addressing SO2 emissions, the Clean Air Act Amendments of 1990 set an SO2 

emissions cap on all power generation, but permitted flexibility among generators 

through the use of emissions allowances and tradable permits. This SO2 trading process 

(sometimes called “cap and trade”) implies that the standard will have virtually no affect 

on total physical emissions because emissions will always be at, or near, the allowed 

emissions ceiling. Consequently, there is no direct SO2 environmental benefit from a 

reduction in electricity use due to the proposed energy conservation standards, as long as 

there is enforcement of the emissions ceiling. But to the extent reduced power generation 

demand decreases the demand for and price of emissions allowance permits, there is an 

environmentally related economic benefit from the proposed energy conservation 

standards reducing SO2 emissions allowance demand. Furthermore, over time, if 

emissions decline, there is greater flexibility in reducing the ceiling amount. 

Nitrogen Oxides (NOx) 

Nitrogen oxides, or NOx, are the generic term for a group of highly reactive gases, 

all of which contain nitrogen and oxygen in varying amounts. Many of the nitrogen 

oxides are colorless and odorless. However, one common pollutant, nitrogen dioxide 

(NO2), along with particles in the air can often be seen as a reddish-brown layer over 

many urban areas. NO2 is the specific form of NOx reported in this document. NOx is 

one of the main ingredients involved in the formation of ground-level ozone, which can 

trigger serious respiratory problems. It can contribute to the formation of acid rain, and 

can impair visibility in areas such as national parks. NOx also contributes to the 

formation of fine particles that can impair human health. 

Nitrogen oxides form when fossil fuel is burned at high temperatures, as in a 

combustion process. The primary manmade sources of NOx are motor vehicles, electric 

utilities, and other industrial, commercial, and residential sources that burn fossil fuels. 

NOx can also be formed naturally. Electric utilities account for about 22 percent of NOx

emissions in the United States. 

Mercury 

Coal-fired power plants emit mercury found in coal during the burning process. 

While coal-fired power plants are the largest remaining source of human-generated 

mercury emissions in the United States, they contribute very little to the global mercury 

pool or to contamination of U.S. waters. U.S. coal-fired power plants emit mercury in 

three different forms: oxidized mercury (likely to deposit within the United States); 

elemental mercury, which can travel thousands of miles before depositing to land and 

water; and mercury that is in particulate form. Atmospheric mercury is deposited on 

land, lakes, rivers, and estuaries through rain, snow, and dry deposition, Once there, it 

can transform into methyl mercury and accumulate in fish tissue through 

bioaccumulation. 

16-2
Americans are exposed to methyl mercury primarily by eating contaminated fish. 

Because the developing fetus is the most sensitive to the toxic effects of methyl mercury, 

women of childbearing age are regarded as the population of greatest concern. Children 

exposed to methyl mercury before birth may be at increased risk of poor performance on 

neurobehavioral tasks, such as those measuring attention, fine motor function, language 

skills, visual-spatial abilities, and verbal memory. 

Carbon Dioxide (CO2) 

Carbon dioxide (CO2) is not a regulated or criteria pollutant (see below), but it is 

of interest because of its classification as a greenhouse gas (GHG). GHGs trap the sun’s 

radiation inside the Earth’s atmosphere and either occur naturally in the atmosphere or 

result from human activities. Naturally occurring GHGs include water vapor, CO2, 

methane (CH4), nitrous oxide (N2O), and ozone (O3). Human activities, however, add to 

the levels of most of these naturally occurring gases. For example, CO2 is emitted to the 

atmosphere when solid waste, fossil fuels (oil, natural gas, and coal), wood, and wood 

products are burned. During the past 20 years, about three-quarters of anthropogenic 

(i.e., human-made) CO2 emissions resulted from burning fossil fuels. 

Concentrations of CO2 in the atmosphere are naturally regulated by numerous 

processes, collectively known as the “carbon cycle.” The movement of carbon between 

the atmosphere and the land and oceans is dominated by natural processes, such as plant 

photosynthesis. While these natural processes can absorb some of the anthropogenic CO2

emissions produced each year, billions of metric tons are added to the atmosphere 

annually. In the U. S., CO2 emissions from both energy generation and industrial 

processes account for 84.6 percent of total U.S. GHG emissions.7 

16.2.2 Air Quality Regulation 

In 1990, EPA amended Title VI section to the Clean Air Act to phase out in 2010 

hydrochlorofluorocarbons (HCFC) refrigerants, which are commonly used in air 

conditioning systems. The only refrigerant currently used by PTACs and PTHP 

equipment is R-22, a HCFC refrigerant and therefore included in the refrigerant phaseout regulationsb

. Chapter 5 of this TSD, engineering analysis, discusses an analysis to 

characterize the performance and cost implications of using an alternative refrigerant 

(i.e., R-410A) in PTAC and PTHP equipment. Manufacturers interviewed confirmed that 

the industry is planning to switch to R-410A as a substitute refrigerant for R-22 in PTAC 

and PTHP equipment. This conversion is not an impact of this rulemaking. Therefore, 

the effects of this conversion are outside the scope of this environmental analysis. All 

later chapters assume costs and performance of PTAC and PTHP equipment based on R410A refrigerant. 

The Clean Air Act Amendments of 1990 list 188 toxic air pollutants that EPA is 

required to control. EPA has set national air quality standards for six common pollutants 

(also referred to as “criteria” pollutants), two of which are SO2 and NOx. Also, the Clean 

 

b

 EPA’s R-22 phase-out regulations can be found at the EPA home website: 

http://www.epa.gov/ozone/title6/phaseout/hcfcfaqs.html#why_epa. 

16-3
Air Act Amendments of 1990 gave EPA the authority to control acidification and to 

require operators of electric power plants to reduce emissions of SO2 and NOx. Title IV 

of the 1990 amendments established a cap-and-trade program for SO2 intended to help 

control acid rain. This cap-and-trade program serves as a model for more recent 

programs with similar features. 

In 2005, EPA issued the Clean Air Interstate Rule (CAIR) under sections 110 and 

111 of the Clean Air Act (40 CFR Parts 51, 96, and 97).c CAIR would have permanently 

capped emissions of SO2 and NOx in eastern States of the United States. CAIR was 

intended to achieve additional large reductions of SO2 and/or NOx emissions across 28 

eastern states and the District of Columbia. States were to achieve the required emission 

reductions using one of two compliance options: 1) meet an emission budget for each 

regulated state by requiring power plants to participate in an EPA-administered interstate 

cap-and-trade system that caps emissions in two stages, or 2) meet an individual state 

emissions budget through measures of the state’s choosing. Phase 1 caps for NOx were to 

be in place in 2009. Phase 1 caps for SO2 were to be in place in 2010. The Phase 2 caps 

for both pollutants were due in 2015. 

Also in 2005, EPA issued the final rule entitled “Standards of Performance for 

New and Existing Stationary Sources: Electric Steam Generating Units,” under 

sections 110 and 111 of the Clean Air Act (40 CFR Parts 60, 63, 72, and 75). This rule, 

also called the Clean Air Mercury Rule, was closely related to the CAIR and established 

standards of performance for mercury emissions from new and existing coal-fired electric 

utility steam generating units. The Clean Air Mercury Rule regulated mercury emissions 

from coal-fired power plants. On February 8, 2008, the U.S. Court of Appeals for the 

District of Columbia Circuit (D.C. Circuit) issued its decision in State of New Jersey, et 

al. v. Environmental Protection Agency,

d

 in which the Court, among other actions, 

vacated the Clean Air Mercury Rule. 

On July 11, 2008, the U.S. Court of Appeals for the District of Columbia Circuit 

(D.C. Circuit) issued its decision in North Carolina v. Environmental Protection Agency, 

which vacated the Clean Air Interstate Rule (CAIR) issued by the U.S. Environmental 

Protection Agency on March 10, 2005.e

 CAIR was the basis under which NOx emissions 

were capped.

f

 However, Even though the D.C. Circuit vacated the CAIR, DOE notes that 

the D.C. Circuit left intact a voluntary program set in place by EPA's 1998 NOX SIP Call 

rule, which provided 23 jurisdictions with an option to implement a cap and trade 

emission program for NOX emissions. See 63 Fed. Reg. 57356, 57359 (Oct. 27, 1998).g

 

c

 See http://www.epa.gov/cleanairinterstaterule/. 

d

 No. 05-1097, 2008 WL 341338, at *1 (D.C. Cir. Feb. 8, 2008). 

e

 See http://www.epa.gov/cleanairinterstaterule/. 

f

 Case No. 05-1244, 2008 WL 2698180 at *1 (D.C. Cir. July 11, 2008). 

g

 In the NOx SIP Call rule, EPA found that sources in the District of Columbia and 22 “upwind” states 

(States) were emitting NOx (an ozone precursor) at levels that significantly contributed to “downwind” 

states not attaining the ozone NAAQS or at levels that interfered with states in attainment maintaining the 

ozone NAAQS. In an effort to ensure that “downwind” states attain or continue to attain the ozone 

NAAQS, EPA established a region-wide cap for NOx emissions from certain large combustion sources and 

set a NOx emissions budget for each State. In order to comply with the NOx SIP Call Rule, States could 

elect to participate in the NOx Budget Trading Program. Under the NOx Budget Trading Program, each 

16-4
16.2.3 Global Climate Change 

Climate change has evolved into a matter of global concern because it is expected 

to have widespread, adverse effects on natural resources and systems. A growing body of 

evidence points to anthropogenic sources of greenhouse gases, such as carbon dioxide 

(CO2), as major contributors to climate change. Because this Rule, if finalized, will 

likely decrease CO2 emission rates from the fossil fuel sector in the United States, the 

Department here examines the impacts and causes of climate change and then the 

potential impact of the Rule on CO2 emissions and global warming. 

Impacts of Climate Change on the Environment 

 

Climate is usually defined as the average weather, over a period ranging from 

months to many years. Climate change refers to a change in the state of the climate, 

which is identifiable through changes in the mean and/or the variability of its properties 

(e.g., temperature or precipitation) over an extended period, typically decades or longer. 

The World Meteorological Organization and United Nations Environment 

Programme (UNEP) established the Intergovernmental Panel on Climate Change (IPCC) 

to provide an objective source of information about climate change. According to the 

IPCC Fourth Assessment Report (IPCC Report), published in 2007, climate change is 

consistent with observed changes to the world’s natural systems; the IPCC expects these 

changes to continue. 

Changes that are consistent with warming include warming of the world’s oceans 

to a depth of 3000 meters; global average sea level rise at an average rate of 1.8 mm per 

year from 1961 to 2003; loss of annual average Arctic sea ice at a rate of 2.7 % per 

decade, changes in wind patterns that affect extra-tropical storm tracks and temperature 

patterns, increases in intense precipitation in some parts of the world, as well as increased 

drought and more frequent heat waves in many locations worldwide, and numerous 

ecological changes. 

Looking forward, the IPCC describes continued global warming of about 0.2°C 

per decade for the next two decades under a wide range of emission scenarios for carbon 

dioxide (CO2), other greenhouse gases (GHG)s, and aerosols. After that period, the rate 

of increase is less certain. The IPCC Report describes increases in average global 

temperatures of about 1.1°C to 6.4°C at the end of the century relative to today. These 

increases vary depending on the model and emissions scenarios. 

The IPCC Report describes incremental impacts associated with the rise in 

temperature. At ranges of incremental increases to the global average temperature, IPCC 

reports, with either high or very high confidence, that there is likely to be an increasing 

 emission source is required to have one allowance for each ton of NOx emitted during the ozone season. 

States have flexibility in how they allocate allowances through their State Implementation Plans but States 

must remain within the EPA-established budget. Emission sources are allowed to buy, sell and bank NOx

allowances as appropriate. It should be noted that, on April 16, 2008, EPA determined that Georgia is no 

longer subject to the NOx SIP Call rule . 73 FR 21528 (April 22, 2008). 

16-5
degree of impacts such as coral reef bleaching, loss of wildlife habitat, loss to specific 

ecosystems, and negative yield impacts for major cereal crops in the tropics, but also 

projects that there likely will be some beneficial impacts on crop yields in temperate 

regions. 

Causes of Climate Change

The IPCC Report states that the world has warmed by about 0.74°C in the last 

100 years. The IPCC Report finds that most of the temperature increase since the mid20th century is very likely due to the increase in anthropogenic concentrations of CO2

and other long-lived greenhouse gases (GHGs) such as methane and nitrous oxide in the 

atmosphere, rather than from natural causes. 

Increasing the CO2 concentration partially blocks the earth’s re-radiation of 

captured solar energy in the infrared band, inhibits the radiant cooling of the earth, and 

thereby alters the energy balance of the planet, which gradually increases its average 

temperature. The IPCC Report estimates that currently, CO2 makes up about 77% of the 

total CO2-equivalenth

 global warming potential in GHGs emitted from human activities, 

with the vast majority (74%) of the CO2 attributable to fossil fuel use. For the future, the 

IPCC Report describes a wide range of GHG emissions scenarios, but under each 

scenario CO2 would continue to comprise above 70% of the total global warming 

potential. 

Stabilization of CO2 Concentrations 

Unlike many traditional air pollutants, CO2 mixes thoroughly in the entire 

atmosphere and is long-lived. The residence time of CO2 in the atmosphere is long 

compared to the emission processes. Therefore, the global cumulative emissions of CO2 

over long periods determine CO2 concentrations because it takes hundreds of years for 

natural processes to remove the CO2. Globally, 49 billion metric tons of CO2 –equivalent 

of anthropogenic (man-made) greenhouse gases are emitted every year. Of this annual 

total, fossil fuels contribute about 29 billion metric tons of CO2.

i

 

Researchers have focused on considering atmospheric CO2 concentrations that 

likely will result in some level of global climate stabilization, and the emission rates 

associated with achieving the “stabilizing” concentrations by particular dates. They 

associate these stabilized CO2 concentrations with temperature increases that plateau in a 

defined range. For example, at the low end, the IPCC Report scenarios target CO2 

stabilized concentrations range between 350 ppm and 400 ppm (essentially today’s 

 

h GHGs differ in their warming influence (radiative forcing) on a global climate system due to their 

different radiative properties and lifetimes in the atmosphere. These warming influences may be expressed 

through a common metric based on the radiative forcing of CO2, i.e., CO2-equivalent. CO2 equivalent 

emission is the amount of CO2 emission that would cause the same- time integrated radiative forcing, over 

a given time horizon, as an emitted amount of other long- lived GHG or mixture of GHGs.

i

 Other non-fossil fuel contributors include CO2 emissions from deforestation and decay from agriculture 

biomass; agricultural and industrial emissions of methane; and emissions of nitrous oxide and 

fluorocarbons. 

16-6
value)—because of climate inertia, concentrations in this low end range would still result 

in temperatures projected to increase 2.0°C to 2.4°C above pre-industrial levelsj

 (about 

1.3oC to 1.7oC above today’s levels). To achieve concentrations between 350 ppm to 400 

ppm, the IPCC scenarios present that there would have to be a rapid downward trend in 

total annual global emissions of greenhouse gases to levels that are 50% to 85% below 

today’s annual emission rates by no later than 2050. Since it is assumed that there would 

continue to be growth in global populations and substantial increases in economic 

production, the scenarios identify required reductions in greenhouse gas emissions 

intensity (emissions per unit of output) of more than 90%. However, even at these rates, 

the scenarios describe some warming and some climate change is projected due to 

already accumulated CO2 and GHGs in the atmosphere. 

The Beneficial Impact of the Rule on CO2 Emissions 

If finalized, it is anticipated that the Rule will reduce energy-related CO2

emissions, particularly those associated with energy consumption in buildings. In the 

United States, the U.S. Energy Information Administration reports in its 2008 Annual 

Energy Outlook (AEO 2008)k

 that U.S. annual energy-related emissions of CO2 in 2005 

were about 5.98 billion metric tons (about 20% of the world energy-related CO2 

emissions and about 12% of total global greenhouse gas emissions), of which 2.32 billion 

tons were attributed to residential and commercial buildings sector (including related 

energy–using equipment such as PTACs and PTHPs). Most of the greenhouse gas 

emissions attributed to residential and commercial buildings are emitted from fossil fuelfired power plants that generate electricity used in this sector. In the AEO2008 reference 

case, EIA projected that annual energy-related CO2 emissions would grow from 6.0 

billion metric tons in 2005 to 6.85 billion metric tons in 2030, an increase of 14.5% (see 

Table 16.2.2, based on AEO 2008), while emissions attributable to buildings would grow 

to 2.92 billion tons, an increase of 26.1%. 

As computed for the AEO 2008 reference case, the cumulative U.S. energyrelated CO2 emissions between 2012 and 2042 are described at about 209 billion metric 

tons. The estimated cumulative CO2 emission reductions from a PTAC and PTHP 

Efficiency Standard (shown as a range of alternative Trial Standard Levels) during this 

same 30-year period are indicated in Table 16.2.1. The estimated CO2 emission 

reductions in Table 16.2.1 are calculated using NEMS-BT model. 

 

j

 IPCC Working Group 3 Table TS 2 

k

 www.eia.doe.gov/oiaf/archive/aeo08/index.html 

16-7
Table 16.2.1 Impact of the PTAC and PTHP Efficiency Standard on Cumulative 

Energy-Related Emissions of CO2 Between 2012 and 2042 by Trial 

Standard Level (Millions of Metric Tons CO2) 

TSL 1 TSL 2 TSL 3 TSL A TSL 4 TSL 5 TSL 6 

Standard Size PTACs and 

PTHPS* 

- 0.49 - 0.81 - 1.05 - 1.06 - 1.09 - 1.68 - 2.34 

TSL 1 TSL 2 TSL 3 TSL 4 TSL 5 

Non-Standard PTACs 

and PTHPs 

- 0.12 -0.14 - 0.18 - 0.20 - 0.29 

* All results in metric tons, equivalent to 1.1 short tons and negative values refer to a reduction compared with the Base Case 

The estimated savings shown in Table 16.2.1, which are at most 0.001 percent of 

U.S. energy-related emissions of CO2 (TSL 6 for Standard Size PTACs and PTHPs), 

comprise an even smaller fraction of U.S. emissions of greenhouse gases and of world 

emissions of greenhouse gases. However, the savings would likely reduce overall U.S. 

CO2 emissions, as compared to U.S. CO2 emissions absent an increase in the required 

efficiency of PTACs and PTHPs. 

The Incremental Impact of the Rule on Climate Change 

It is difficult to correlate specific emission rates with atmospheric concentrations 

of CO2 and specific atmospheric concentrations with future temperatures because the 

IPCC Report describes a clear lag in the climate system between any given concentration 

of CO2 (even if maintained for long periods) and the subsequent average worldwide and 

regional temperature, precipitation, and extreme weather regimes. For example, a major 

determinant of climate response is “equilibrium climate sensitivity”, a measure of the 

climate system response to sustained radioactive forcing. It is defined as the global 

average surface warming following a doubling of carbon dioxide concentrations. The 

IPCC Report describes its estimated, numeric value as about 3°C, but the likely range of 

that value is 2°C to 4.5°C, with cloud feedbacks the largest source of uncertainty. 

Further, as illustrated above, the IPCC Report scenarios for stabilization rates are 

presented in terms of a range of concentrations, which then correlates to a range of 

temperature changes. Thus, climate sensitivity is a key uncertainty for CO2 mitigation 

scenarios that aim to meet specific temperature levels. 

 

Because of how complex global climate systems are, it is difficult to know to 

what extent and when particular CO2 emissions rates will impact global warming. 

However, as Table 16.2.1 indicates, the Rule will likely reduce CO2 emissions rates from 

the fossil fuel sector. 

16.2.4 Analytical Methods for Air Emissions 

NEMS-BT incorporates capabilities to assess compliance with SO2 restrictions 

specified in the Clean Air Act and its amendments. Clean air act provisions include New 

16-8
Source Performance Standards, and Revised New Source Performance Standards. The 

version of NEMS-BT in 2008 also included provisions for the Clean Air Interstate Rule 

(CAIR), which imposes stricter restrictions on SO2 and NOx for some states, and the 

Clean Air Mercury Rule CAMR), which imposed a national mercury (Hg) constraint. On 

July 11, 2008, the U.S. Court of Appeals for the District of Columbia Circuit (D.C. 

Circuit) issued its decision in North Carolina v. Environmental Protection Agency, 

vacating the CAIR. 531 F.3d 896 (D.C. Cir. 2008). Although the constraints on NOx in 

CAIR and mercury in CAMR have since been vacated by a court decision, the AEO 2008 

reference case assumes that emissions of NOx and mercury would decline over time as 

shown in Table 16.2.2. 

 Because the courts vacated CAIR and CAMR, the 2008 version of NEMS-BT 

could not be used directly to estimate emissions impacts for NOx and mercury. Instead, 

DOE established a range of NOx reductions due to standards. DOE’s high estimate was 

based on the use of a nationwide NOx emission rate for electrical generation. DOE 

derived a current NOx emission rate for the power sector based on data from the AEO 

2008. DOE based the emission rate on the tons of NOX emitted per TWh of electricity 

generated in 2006. Use of such an emission rate assumes that future energy conservation 

standards would result in displaced electrical generation mix that is equivalent to today’s 

mix of power plants (i.e., future power plants displaced are no cleaner than what are 

being used currently to generate electricity). In addition, under the high estimate 

assumption, energy conservation standards would have little to no effect on the 

generation mix. Based on AEO2008 for a recent year (2006) in which no regulatory or 

non-regulatory measures were in effect to limit NOX emissions, DOE multiplied this 

emission rate by the reduction in electricity generation due to the standards considered. 

For 2006, the NOx emission rate was 0.843 kt/TWh. DOE’s low estimate was based on 

the use of an emission rate for new combined-cycle gas plants as provided in the NEMSBT. This emission rate equals 0.0341 kt/TWh and represents the lowest emission rate of 

fossil-fuel based generation that might be displaced under standards. To estimate the 

reduction in NOX emissions, DOE multiplied this emission rate by the reduction in 

electricity generation due to the standards considered. The range in NOX emission 

changes calculated using the low and high estimate scenarios are shown by TSL for 

standard-sized and non-standard size PTACs and PTHPS in Table 16.2.3, Table 16.2.4, 

Table 16.2.5 and Table 16.2.6 for the period from 2012 to 2042. 

DOE also is able to report an estimate of the physical quantity changes in mercury 

(Hg) emissions associated with an energy conservation standard. As opposed to using the 

NEMS-BT model, DOE established a range of Hg reductions due to standards. DOE’s 

high estimate used a mercury emission rate based on the AEO 2008. Because virtually 

all mercury emitted from electricity generation is from coal-fired power plants, DOE 

based the emission rate on the tons of mercury emitted per TWh of coal-generated 

electricity. Because power plant emission rates are a function of local regulation, 

scrubbers, and the mercury content of coal, it is extremely difficult to come up with a 

precise high-end emission rate. Therefore, DOE believes the most reasonable estimate is 

16-9
based on the assumption that all displaced coal generation would have been emitting at 

the average emission rate for coal generation as specified by AEO2008. 

 DOE based the emission rate on the average value reported in the AEO 2008 for 

2006. This emission rate is 0.0255 tons per TWh. DOE’s low estimate was based on the 

use of an emission rate for new combined-cycle gas plants as provided in the NEMS-BT. 

The emission rate for this generation technology is 0.000 tons per TWh. To estimate the 

reduction in mercury emissions, DOE multiplied the emission rate by the reduction in 

coal-generated electricity due to the standards considered as determined in the utility 

impact analysis. The estimated changes in Hg emissions are shown in by TSL for 

standard-sized and non-standard size PTACs and PTHPS in Table 16.2.3 through Table 

16.2.6 for the period from 2012 to 2042. 

Coal-fired electric generation is the single largest source of electricity in the 

United States. Because the mix of coals used significantly affects the emissions 

produced, the model includes a detailed representation of coal supply. The model 

considers the rank of the coal as well as the sulfur contents of the fuel used when 

determining optimal dispatch. 

Within the NEMS-BT model, planning options for achieving emissions 

restrictions in the Clean Air Act Amendments include installing pollution control 

equipment on existing power plants and building new power plants with low emission 

rates. These methods for reducing emission are compared to dispatching options such as 

fuel switching and allowance trading. Environmental regulations also affect capacity 

expansion decisions. For instance, new plants are not allocated SO2 emissions 

allowances according to the Clean Air Act Amendments. Consequently, the decision to 

build a particular capacity type must consider the cost (if any) of obtaining sufficient 

allowances. This could involve purchasing allowances or over complying at an existing 

unit. 

Modeling of SO2 trading tends to imply that the physical emissions effects will be 

zero, as long as emissions are at the allowed ceiling. Because SO2 has been regulated 

with emissions caps for more than a decade, and no emissions reductions are reported 

from the NEMS-BT forecast model, DOE does not report SO2 results here. This 

assumption is consistent with previous DOE environmental assessment documents.1

As noted in Chapter 14, NEMS-BT model forecasts end in year 2030. Emissions 

impacts beyond 2030 were extrapolated for this rulemaking in Table 16.2.3 through 

Table 16.2.6. 

16.2.5 Effects on Power Plant Emissions 

Table 16.2.2 shows reference power plant emissions in selected years. The 

Annual Energy Outlook (AEO) 2008 Reference case emissions are the emissions shown 

by the NEMS-BT model to result if none of the TSLs are promulgated. Table 16.2.3

through Table 16.2.6 show estimated changes in emissions in selected years for all the 

PTAC and PTHP equipment under each of seven TSLs, grouping for standard size 

16-10
PTACs and PTHPs and five TSLs for non-standard size PTACs and PTHPs. Changes in 

NO2 and mercury emissions from power plants are shown in these tables. Changes in 

CO2 emissions from all sources are also shown in these four tables. 

Table 16.2.2 Emissions Forecast for AEO 2008 Reference Case 

NEMS-BT Results: 

 2005 2010 2015 2020 2025 2030 

CO2 (Million metric tons/year) *,** 2,397 2,413 2,519 2,627 2,771 2,948 

NOX (Thousand tons/year)† 3,639 2,338 2,112 2,112 2,142 2,169 

Hg (tons/year)† 51.72 37.24 24.19 18.48 16.69 15.41 

* Metric tons, equivalent to 1.1 short tons 

** Emissions from all energy-related sources 

† Emissions from electric generation . 

Compared to the anticipated reference case emissions impacts forecast shown in 

Table 16.2.2, changes in emission levels shown in Table 16.2.3 through Table 16.2.6 are 

extremely small. In general, the NEMS-BT model results show a general trend toward 

slightly reduced emission levels over time for most if not all the equipment types. 

16-11
Table 16.2.3 Emissions Impact Forecasts for Standard Size PTACs 

NEMS-BT Results: Difference from Reference Case 

 Extrapolation 

 2015 2020 2025 2030 2035 2040 2042 

Trial Standard Levels 1,2,4 

CO2 (Million metric tons/year) -0.006 -0.009 -0.009 -0.005 -0.005 -0.005 -0.005 

NOx (Thousand tons/year) 

 High -0.0043 -0.0084 -0.0113 -0.0129 -0.0129 -0.0129 -0.0129 

 Low -0.0002 -0.0003 -0.0005 -0.0005 -0.0005 -0.0005 -0.0005 

Hg (tons/year) 

 High -0.0002 -0.0003 -0.0003 -0.0002 -0.0002 -0.0002 -0.0002 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level 3 

CO2 (Million metric tons/year) -0.013 -0.021 -0.021 -0.012 -0.012 -0.012 -0.012 

NOx (Thousand tons/year) 

 High -0.0095 -0.0188 -0.0252 -0.0288 -0.0288 -0.0288 -0.0288 

 Low -0.0004 -0.0008 -0.0010 -0.0012 -0.0012 -0.0012 -0.0012 

Hg (tons/year) 

 High -0.0005 -0.0008 -0.0007 -0.0004 -0.0004 -0.0004 -0.0004 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level A 

CO2 (Million metric tons/year) -0.008 -0.014 -0.014 -0.008 -0.008 -0.008 -0.008 

NOx (Thousand tons/year) 

 High -0.0062 -0.0122 -0.0163 -0.0186 -0.0186 -0.0186 -0.0186 

 Low -0.0002 -0.0005 -0.0007 -0.0008 -0.0008 -0.0008 -0.0008 

Hg (tons/year) 

 High -0.0003 -0.0005 -0.0005 -0.0003 -0.0003 -0.0003 -0.0003 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level 5 

CO2 (Million metric tons/year) -0.023 -0.037 -0.037 -0.022 -0.022 -0.022 -0.022 

NOx (Thousand tons/year) 

 High -0.0169 -0.0333 -0.0447 -0.0509 -0.0509 -0.0509 -0.0509 

 Low -0.0007 -0.0013 -0.0018 -0.0021 -0.0021 -0.0021 -0.0021 

Hg (tons/year) 

 High -0.0008 -0.0013 -0.0013 -0.0007 -0.0007 -0.0007 -0.0007 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level 6 

CO2 (Million metric tons/year) -0.035 -0.057 -0.057 -0.033 -0.033 -0.033 -0.033 

NOx (Thousand tons/year) 

 High -0.0259 -0.0512 -0.0686 -0.0782 -0.0782 -0.0782 -0.0782 

 Low -0.0010 -0.0021 -0.0028 -0.0032 -0.0032 -0.0032 -0.0032 

Hg (tons/year) 

 High -0.0013 -0.0021 -0.0020 -0.0011 -0.0011 -0.0011 -0.0011 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

* Negative values refer to a reduction compared with the Base Case 

16-12
Table 16.2.4 Emissions Impact Forecasts for Non-Standard Size PTACs 

NEMS-BT Results: Difference from Reference Case 

 Extrapolation 

 2015 2020 2025 2030 2035 2040 2042 

Trial Standard Levels 1&2 

CO2 (Million metric tons/year) -0.002 -0.003 -0.003 -0.002 -0.002 -0.002 -0.002 

NOx (Thousand tons/year) 

 High -0.0013 -0.0026 -0.0035 -0.0040 -0.0040 -0.0040 -0.0040 

 Low -0.0001 -0.0001 -0.0001 -0.0002 -0.0002 -0.0002 -0.0002 

Hg (tons/year) 

 High -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

 

Trial Standard Level 3 

CO2 (Million metric tons/year) -0.003 -0.005 -0.005 -0.003 -0.003 -0.003 -0.003 

NOx (Thousand tons/year) 

 High -0.0022 -0.0043 -0.0057 -0.0065 -0.0065 -0.0065 -0.0065 

 Low -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 

Hg (tons/year) 

 High -0.0001 -0.0002 -0.0002 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

 

Trial Standard Levels 4 

CO2 (Million metric tons/year) -0.002 -0.003 -0.003 -0.002 -0.004 -0.004 -0.004 

NOx (Thousand tons/year) 

 High -0.0013 -0.0026 -0.0035 -0.0040 -0.0100 -0.0100 -0.0100 

 Low -0.0001 -0.0001 -0.0001 -0.0002 -0.0002 -0.0002 -0.0002 

Hg (tons/year) 

 High -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

 

Trial Standard Level 5 

CO2 (Million metric tons/year) -0.004 -0.007 -0.007 -0.004 -0.0043 -0.0043 -0.0043 

NOx (Thousand tons/year) 

 High -0.0033 -0.0066 -0.0088 -0.0100 -0.0100 -0.0100 -0.0100 

 Low -0.0001 -0.0003 -0.0004 -0.0004 -0.0004 -0.0004 -0.0004 

Hg (tons/year) 

 High -0.0002 -0.0003 -0.0003 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

16-13
Table 16.2.5 Emissions Impact Forecasts for Standard Size PTHPs 

NEMS-BT Results: Difference from Reference Case 

 Extrapolation 

 2015 2020 2025 2030 2035 2040 2042 

Trial Standard Levels 1,2,4 

CO2 (Million metric tons/year) -0.010 -0.016 -0.015 -0.006 -0.006 -0.006 -0.006 

NOx (Thousand tons/year) 

 High -0.0866 -0.1716 -0.2308 -0.2642 -0.2642 -0.2642 -0.2642 

 Low -0.0035 -0.0069 -0.0093 -0.0107 -0.0107 -0.0107 -0.0107 

Hg (tons/year) 

 High -0.0003 -0.0005 -0.0005 -0.0003 -0.0003 -0.0003 -0.0003 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level 3 

CO2 (Million metric tons/year) -0.021 -0.034 -0.031 -0.013 -0.013 -0.013 -0.013 

NOx (Thousand tons/year) 

 High -0.1812 -0.3591 -0.4830 -0.5530 -0.5530 -0.5530 -0.5530 

 Low -0.0073 -0.0145 -0.0195 -0.0224 -0.0224 -0.0224 -0.0224 

Hg (tons/year) 

 High -0.0006 -0.0010 -0.0010 -0.0006 -0.0006 -0.0006 -0.0006 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level A 

CO2 (Million metric tons/year) -0.027 -0.043 -0.039 -0.016 -0.016 -0.016 -0.016 

NOx (Thousand tons/year) 

 High -0.2297 -0.4552 -0.6123 -0.7009 -0.7009 -0.7009 -0.7009 

 Low -0.0093 -0.0184 -0.0248 -0.0284 -0.0284 -0.0284 -0.0284 

Hg (tons/year) 

 High -0.0008 -0.0013 -0.0013 -0.0007 -0.0007 -0.0007 -0.0007 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level 5 

CO2 (Million metric tons/year) -0.031 -0.049 -0.045 -0.019 -0.019 -0.019 -0.019 

NOx (Thousand tons/year) 

 High -0.2648 -0.5247 -0.7058 -0.8080 -0.8080 -0.8080 -0.8080 

 Low -0.0107 -0.0212 -0.0286 -0.0327 -0.0327 -0.0327 -0.0327 

Hg (tons/year) 

 High -0.0009 -0.0015 -0.0015 -0.0008 -0.0008 -0.0008 -0.0008 

 Low 0.0000 0.0000 0.0000 0.0000 

Trial Standard Level 6 

CO2 (Million metric tons/year) -0.039 -0.062 -0.057 -0.023 -0.023 -0.023 -0.023 

NOx (Thousand tons/year) 

 High -0.3351 -0.6641 -0.8933 -1.0227 -1.0227 -1.0227 -1.0227 

 Low -0.0136 -0.0269 -0.0361 -0.0414 -0.0414 -0.0414 -0.0414 

Hg (tons/year) 

 High -0.0011 -0.0019 -0.0018 -0.0010 -0.0010 -0.0010 -0.0010 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

16-14
Table 16.2.6 Emissions Impact Forecasts for Non-Standard Size PTHPs 

NEMS-BT Results: Difference from Reference Case 

 Extrapolation 

 2015 2020 2025 2030 2035 2040 2042 

Trial Standard Level 1 

CO2 (Million metric tons/year) -0.002 -0.003 -0.003 -0.001 -0.001 -0.001 -0.001 

NOx (Thousand tons/year) 

 High -0.0180 -0.0357 -0.0480 -0.0549 -0.0549 -0.0549 -0.0549 

 Low -0.0007 -0.0014 -0.0019 -0.0022 -0.0022 -0.0022 -0.0022 

Hg (tons/year) 

 High -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

 

Trial Standard Levels 2&3 

CO2 (Million metric tons/year) -0.003 -0.005 -0.004 -0.002 -0.002 -0.002 -0.002 

NOx (Thousand tons/year) 

 High -0.0247 -0.0489 -0.0657 -0.0753 -0.0753 -0.0753 -0.0753 

 Low -0.0010 -0.0020 -0.0027 -0.0030 -0.0030 -0.0030 -0.0030 

Hg (tons/year) 

 High -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

 

Trial Standard Levels 4&5 

CO2 (Million metric tons/year) -0.005 -0.008 -0.007 -0.003 -0.003 -0.003 -0.003 

NOx (Thousand tons/year) 

 High -0.0416 -0.0824 -0.1109 -0.1269 -0.1269 -0.1269 -0.1269 

 Low -0.0017 -0.0033 -0.0045 -0.0051 -0.0051 -0.0051 -0.0051 

Hg (tons/year) 

 High -0.0001 -0.0002 -0.0002 -0.0001 -0.0001 -0.0001 -0.0001 

 Low 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 

16.2.6 Effects on Upstream Fuel-Cycle Emissions 

Fuel-cycle emissions refer to the emissions associated with the amount of energy 

used in the upstream production and downstream consumption of electricity, including 

energy used at the power plant. Upstream processes include the mining of coal or 

extraction of natural gas, physical preparatory and cleaning processes, and transportation 

to the power plant. The NEMS-BT does a thorough accounting of emissions at the power 

plant due to downstream energy consumption, but does not account for upstream 

emissions (i.e., emissions from energy losses during coal and natural gas production). 

Thus, this analysis reports only power plant emissions. 

However, previous DOE environmental assessment documents have developed 

qualitative estimates of affects on upstream fuel-cycle emissions. These emissions 

16-15
factors provide the reader with a sense of the possible magnitude of upstream effects. 

These upstream emissions would be in addition to emissions from direct combustion. 

Relative to the entire fuel cycle, estimates based on the work of Dr. Mark DeLuchi, and 

reported in earlier DOE environmental assessment documents, find that an amount 

approximately equal to eight percent, by mass, of emissions (including SO2) from coal 

production are due to mining, preparation that includes cleaning the coal, and 

transportation from the mine to the power plant.1, 2

 Transportation emissions include 

emissions from the fuel used by the mode of transportation that moves the coal from the 

mine to the power plant. 

In addition, based on Dr. DeLuchi’s work, DOE estimated that approximately an 

amount equal to 14 percent of emissions from natural gas production result from 

upstream processes. Emission factor estimates and corresponding percentages of 

contributions of upstream emissions from coal and natural gas production, relative to 

power plant emissions, are shown in Table 16.2.7 for CO2, and NOx. The percentages 

are relative to power plant emissions and provide a means to estimate upstream emission 

savings based on changes in emissions from power plants. The percentage effects 

presented in Table 15.2.6 provide a qualitative approach to viewing effects on fuel cycle 

emissions. The previous section indicates slight overall reductions in CO2, and NOx. 

Thus, very small reductions in upstream emissions of air pollutant could be expected. 

This approach does not address mercury emissions. 

Table 16.2.7 Estimated Upstream Emissions of Air Pollutants as a Percentage of 

Direct Power Plant Combustion Emissions 

Pollutant 

Percent of Coal 

Combustion Emissions 

Percent of Natural Gas 

Combustion Emissions 

CO2 2.7 11.9 

NOx 5.8 40 

16.2.7 Economic Valuation of Emissions Reductions 

In addition to the estimation of reductions in physical emissions from an energy 

conservation standard, the analysis also considered the monetary benefits associated with 

these reductions. 

Carbon Dioxide (CO2) 

 During the preparation of its most recent review of the state of climate science, the 

Intergovernmental Panel on Climate Change (IPCC) identified various estimates of the 

present value of reducing carbon dioxide emissions by one ton over the life that these 

emissions would remain in the atmosphere. The estimates reviewed by the IPCC spanned 

a range of values. In the absence of a consensus on any single estimate of the monetary 

value of CO2 emissions, DOE used an estimate identified by the study cited in Summary 

for Policymakers prepared by Working Group II of the IPCC’s Fourth Assessment Report 

16-16
to calculate the potential monetary value of the CO2 reductions likely to result from the 

standards under consideration in this rulemaking. 

To put the potential monetary benefits from reduced CO2 emissions into a form 

that is likely to be most useful to decision makers and interested parties, the estimated 

year-by-year reductions in CO2 emissions were converted into monetary values and these 

resulting annual values were then discounted over the life of the affected appliances to 

the present using both 3 percent and 7 percent discount rates. DOE applied an annual 

growth rate of 2.4% to the value of SCC, as suggested by the IPCC Working Group II 

(2007, p. 822), based on estimated increases in damages from future emissions reported 

in published studies. As a result, DOE is assigned a range for the SCC of $0 to $20 

($2007) per ton of CO2 emissions. These estimates were based on an assumption of no 

benefit to an average benefit value reported by the IPCC as the Social Cost of Carbon 

(SCC).l

 The resulting estimates of the potential range of the present value of benefits 

associated with the reduction of CO2 emissions are reflected in Table 16.2.8. 

 

l

 During the preparation of its most recent review of the state of climate science, the Intergovernmental 

Panel on Climate Change (IPCC) identified various estimates of the present value of reducing carbondioxide emissions by one ton over the life that these emissions would remain in the atmosphere. The 

estimates reviewed by the IPCC spanned a range of values. In the absence of a consensus on any single 

estimate of the monetary value of CO2 emissions, DOE used the estimates identified by the study cited in 

Summary for Policymakers prepared by Working Group II of the IPCC’s Fourth Assessment Report to 

estimate the potential monetary value of CO2 reductions likely to result from standards finalized in this 

rulemaking. According to IPCC, the mean social cost of carbon (SCC) reported in studies published in 

peer-reviewed journals was $43 per ton of carbon. This translates into about $12 per ton of carbon dioxide. 

The literature review (Tol 2005) from which this mean was derived did not report the year in which these 

dollars were denominated. However, we understand this estimate was denominated in 1995 dollars. 

Updating that estimate 1995 estimate to 2007 dollars yields a SCC of $15 per ton of carbon dioxide. 

16-17
Table 16.2.8 Estimates of Savings from CO2 Emissions Reductions under PTAC 

and PTHP Trial Standard Levels at 7% Discount Rate and 3% Discount Rate 

Trial Standard 

Level 

Estimated 

Cumulative CO2

(Million metric tons) 

Emission Reductions 

Value of Estimated 

CO2 Emission 

Reductions Based on 

IPCC Range (Million 

2007$) at 7% 

Discount Rate 

Value of Estimated 

CO2 Emission 

Reductions Based on 

IPCC Range (Million 

2007$) at 3% 

Discount Rate 

Standard Size PTACs and PTHPs 

TSL 1 0.49 $0 to $4.8 $0 to $9.0 

TSL 2 0.81 $0 to $8.0 $0 to $14.9 

TSL 3 1.05 $0 to $10.4 $0 to $19.4 

TSL A 1.06 $0 to $10.5 $0 to $19.5 

TSL 4 1.09 $0 to $10.8 $0 to $20.0 

TSL 5 1.68 $0 to $16.5 $0 to $30.9 

TSL 6 2.34 $0 to $22.9 $0 to $43.0 

Non-Standard Size PTACs and PTHPs 

TSL 1 0.12 $0 to $1.2 $0 to $2.2 

TSL 2 0.14 $0 to $1.4 $0 to $2.7 

TSL 3 0.18 $0 to $1.8 $0 to $3.4 

TSL 4 0.20 $0 to $2.0 $0 to $3.7 

TSL 5 0.29 $0 to $2.9 $0 to $5.4 

 The IPCC estimate used as the upper bound value was derived from an estimate of 

the mean value of worldwide impacts from potential climate impacts caused by CO2

emissions, and not just the effects likely to occur within the United States. DOE 

considers that in estimating a monetary value for CO2 emission reductions, the values 

should be restricted to a representation of those costs/benefits likely to be experienced in 

the United States and expects that such values would be lower than comparable global 

values. There currently are no consensus estimates for the U.S. benefits likely to result 

from CO2 emission reductions. However, DOE believes it is appropriate to use U.S. 

benefit values, where available, and not world benefit values, in its analysis.m 

 Given the uncertainty surrounding estimates of the SCC, relying on any single 

study may be inadvisable since its estimate of the SCC will depend on many assumptions 

made by its authors. The Working Group II’s contribution to the Fourth Assessment 

 

m In contrast, most of the estimates of costs and benefits of increasing the efficiency of PTACs and PTHPs 

include only economic values of impacts that would be experienced in the U.S. For example, in 

determining impacts on manufacturers, DOE generally does not consider impacts that occur solely outside 

of the United States. 

16-18
Report of the IPCC notes that: 

The large ranges of SCC are due in the large part to differences in 

assumptions regarding climate sensitivity, response lags, the treatment of 

risk and equity, economic and non-economic impacts, the inclusion of 

potentially catastrophic losses, and discount rates.n

 DOE believes that the most appropriate monetary values for consideration in the 

development of efficiency standards are those drawn from studies that attempt to estimate 

the present value of the marginal economic benefits likely to result from reducing 

greenhouse gas emissions, rather than estimates that are based on the market value of 

emission allowances under existing cap and trade programs or estimates that are based on 

the cost of reducing emissions - both of which are largely determined by policy decisions 

that set the timing and extent of emission reductions and do not necessarily reflect the 

benefit of reductions. DOE also believes that the studies it relies upon generally should 

be studies that were the subject of a peer review process and were published in reputable 

journals. 

 The upper bound of the range used by DOE is based on Tol (2005), which reviewed 

103 estimates of the SCC from 28 published studies, and concluded that when only peerreviewed studies published in recognized journals are considered, “that climate change 

impacts may be very uncertain but [it] is unlikely that the marginal damage costs of 

carbon dioxide emissions exceed $50 per ton carbon [comparable to a 2007 value of $20 

per ton carbon dioxide when expressed in 2007 U.S. dollars with a 2.4% growth rate.]” 

 In setting a lower bound of $0, DOE agrees with the IPCC Working Group II 

(2007) report that “significant warming across the globe and the locations of significant 

observed changes in many systems consistent with warming is very unlikely to be due 

solely to natural variability of temperatures or natural variability of the systems” (pp. 9), 

and thus tentatively concludes that a global value of zero for reducing emissions cannot 

be justified. However, DOE also believes that it is reasonable to allow for the possibility 

that the U.S. portion of the global cost of carbon dioxide emissions may be quite low. In 

fact, some of the studies looked at in Tol (2005) reported negative values for the SCC. 

As stated in the NOPR, DOE is using U.S. benefit values, and not world benefit values, 

in its analysis and, further, DOE believes that U.S. domestic values will be lower than the 

global values. Additionally, the statutory criteria in EPCA do not require consideration 

of global effects. Therefore, DOE is using a lower bound of $0 per ton of CO2 emissions 

in estimating the potential benefits. 

Nitrogen Oxides (NOx) and Mercury 

 DOE also investigated the monetary impact of efficiency standards on NOx, 

 

n Climate Change 2007 – Impacts, Adaptation and Vulnerability 

Contribution of Working Group II to the Fourth Assessment Report of the IPCC, 17. Available at

http://www.ipcc-wg2.org (last accessed Aug. 7, 2008). 

16-19
mercury (Hg), and SO2,. National SO2 emissions are currently subject to a national cap 

and trade system by regulation while NOx and Hg are not. For the range of NOX

reduction estimates (and Hg reduction estimates), DOE estimated the national monetized 

benefits of emissions reductions based on environmental damage estimates from the 

literature. The effect of the SO2 caps is that equipment efficiency standards will have 

almost no effect on physical emissions of SO2, but if large enough, could cause 

incremental changes in the prices of emissions allowances in cap-and-trade emissions 

markets. 

 Because of the court ruling discussed in Section 16.2.2, emissions of NOx from 

electricity generation are not controlled by the regulatory caps. For these emissions, 

DOE estimated the national monetized benefits of emissions reductions based on 

environmental damage estimates from the literature. Available estimates suggest a very 

wide range of monetary values for NOx emissions, ranging from $370 per ton to $3,800 

per ton of NOx from stationary sources, measured in 2001 dollarso or a range of $432 

per ton to $4,441 per ton in 2007 dollars. 

 

DOE conducted research and determined that the basic science linking mercury 

emissions from power plants to impacts on humans is considered highly uncertain. However, 

DOE located two estimates of the environmental damages of mercury based on two 

estimates of the adverse impact of childhood exposure to methyl mercury on IQ for 

American children, and subsequent loss of lifetime economic productivity resulting from 

these IQ losses. The high-end estimate is based on an estimate of the current aggregate 

cost of the loss of IQ that results from exposure of American children of U.S. power plant 

origin of $1.3 billion per year in year 2000$, which works out to $32.6 million per ton 

emitted per year (2007$).p

 The low-end estimate is $664,000 per ton emitted in 2004$ or 

$729,000 per ton in 2007$), which DOE derived from a published evaluation of mercury 

control using different methods and assumptions from the first study, but also based on 

the present value of the lifetime earnings of children exposed.q The resulting estimates of 

the potential range of the present value benefits associated with the national reduction of 

NOx and Hg emissions are reflected in Table 16.2.9 and Table 16.2.10. 

o

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

State, Local, and Tribal Entities. Office of Management and Budget Office of Information and Regulatory 

Affairs, Washington, D.C. 

p

 Trasande, L., et al., “Applying Cost Analyses to Drive Policy that Protects Children” 1076 ANN. N.Y. 

ACAD. SCI. 911 (2006). 

q

 Ted Gayer and Robert Hahn, Designing Environmental Policy: Lessons from the Regulation of Mercury 

Emissions, Regulatory Analysis 05-01. AEI-Brookings Joint Center For Regulatory Studies, Washington, D.C., 31 

pp., 2004. A version of this paper was published in the Journal of Regulatory Economics in 2006. The 

estimate was derived by back-calculating the annual benefits per ton from the net present value of benefits 

reported in the study. 

16-20
Table 16.2.9 Estimates of Savings from Reductions of NOx and Hg under PTAC 

and PTHP Trial Standard Levels at a 7% Discount Rate 

Trial 

Standard 

Level 

Estimated 

Cumulative NOx 

(kt) Emission 

Reductions 

Value of Estimated 

NOx Emission 

Reductions 

(Thousand 2007$) 

Estimated 

Cumulative Hg 

(tons) Emission 

Reductions 

Value of Estimated 

Hg Emission 

Reductions 

(Thousand 2007$) 

Standard Size PTACs and PTHPs 

TSL 1 0.04-0.94 $4-$1,091 0-0.017 $0-$182 

TSL 2 0.07-1.64 $7-$1892 0-0.028 $0-$299 

TSL 3 0.08-2.02 $9-$2,335 0-0.037 $0-$392 

TSL A 0.09-2.13 $10- $2,462 0-0.037 $0-$393 

TSL 4 0.09-2.25 $10-$2,599 0-0.038 $0-$403 

TSL 5 0.13-3.17 $14-$3,658 0-0.059 $0-$624 

TSL 6 0.18-4.34 $20-$5,014 0-0.082 $0-$871 

Non-Standard Size PTACs and PTHPs 

TSL 1 0.01-0.23 $1-$263 0-0.004 $0-$45 

TSL 2 0.01-0.28 $1-$319 0-0.005 $0-$54 

TSL 3 0.01-0.34 $2-$390 0-0.006 $0-$69 

TSL 4 0.02-0.40 $2-$463 0-0.007 $0-$75 

TSL 5 0.02-0.55 $2-$631 0-0.010 $0-$110 

Table 16.2.10 Preliminary Estimates of Savings from Reductions of NOx and Hg 

under PTAC and PTHP Trial Standard Levels at a 3% Discount Rate 

Trial 

Standard 

Level 

Estimated 

Cumulative NOx 

(kt) Emission 

Reductions 

Value of Estimated 

NOx Emission 

Reductions 

(Thousand 2007$) 

Estimated 

Cumulative Hg 

(tons) Emission 

Reductions 

Value of Estimated 

Hg Emission 

Reductions 

(Thousand 2007$) 

Standard Size PTACs and PTHPs 

TSL 1 0.04-0.94 $9-$2,250 0-0.017 $0-$331 

TSL 2 0.07-1.64 $15-$3,903 0-0.028 $0-$544 

TSL 3 0.08-2.02 $19-$4,815 0-0.037 $0-$712 

TSL A 0.09-2.13 $20- $5,079 0-0.037 $0-$714 

TSL 4 0.09-2.25 $21-$5,362 0-0.038 $0-$732 

TSL 5 0.13-3.17 $30-$7,545 0-0.059 $0-$1,135 

TSL 6 0.18-4.34 $41-$10,341 0-0.082 $0-$1,582 

Non-Standard Size PTACs and PTHPs 

TSL 1 0.01-0.23 $2-$542 0-0.004 $0-$83 

TSL 2 0.01-0.28 $3-$659 0-0.005 $0-$98 

TSL 3 0.01-0.34 $3-$805 0-0.006 $0-$125 

TSL 4 0.02-0.40 $4-$954 0-0.007 $0-$136 

TSL 5 0.02-0.55 $5-$1,301 0-0.010 $0-$200 

16-21
Sulfur Dioxide (SO2) 

Unlike the other pollutants considered in this TSD, SO2 emissions have for some 

time been subject to a national cap with corresponding annual allowances openly traded; 

therefore, considerable market experience with these instruments has already been 

accumulated. It has been argued that imposition of any standard that lowers U.S. national 

electricity consumption creates beneficial downward pressure on the prices of these 

allowances, and this cost reduction benefit should be considered in any analysis of a 

proposed standard. While this assertion is fundamentally sound, i.e. reduced electricity 

demand should ceteris paribus bring about lower SO2 allowance prices, there are a 

myriad of complications impeding any meaningful quantification of any associated 

benefit. While complexity of analysis alone clearly cannot justify disregarding a 

potential consequence of a standard, the Department additionally believes these benefits 

to be both volatile and de minimis when compared to the direct effects of a standard as 

estimated in this TSD. 

Some of the problems to be confronted in an allowance price effect forecast are: 

1. Only any net lowering of the total allowance bill to generators free of transfers is 

the potential source of a benefit. Any such compliance cost saving would need to 

be accurately estimated, and this effect is no different from the benefit derived 

from a cost reduction for other inputs, such as fuel. When the SO2 allowance 

market that was created in 1995 under the Clean Air Act Amendments (CA3) 

began, initial allowance allocations were directly granted to large affected units

based on their historic (1985-87) use of fuel. For 30 years, allowances for the 

following year are issued every spring at a declining rate to these entitled parties, 

and thereafter can be freely used, traded, or banked. Some additional allowances 

are allocated in diverse ways, e.g. as rewards to generators installing control 

equipment. In other words, the entitled generators holding emission rights are 

losers when the value of allowances declines, while the buyers of allowances are 

gainers. Before they are used, allowances may be traded many times at prices 

reflecting the marginal not average cost of compliance. 

2. The trading system allows for allowance banking. Consequently, any observed 

change in a forecast year could represent the manifestation of market 

fundamentals but could similarly just indicate deposit or withdrawal of 

allowances. In general, used allowances have fallen short of the cap so emissions 

may exceed the specified cap for future years. 

3. Control efforts could further reduce the SO2 cap for some jurisdictions, creating 

regulatory uncertainty that perturbs the allowance market. The issuance of the 

proposed and final CAIR rules were likely contributing factors to allowance price 

increases leading to a dramatic 2005 allowance price spike. While prices had 

already fallen far below their historic highs by the time CAIR was vacated in the 

summer of 2008, spot allowance prices nonetheless made a further precipitous 

drop following the D.C. Circuit Court ruling. 

16-22
4. Because allowances can be traded freely by generators, brokers, and investors, 

they can serve as financial instruments, and, especially since 2003, allowance 

prices have been volatile. Between 2000, when a tightened CA3 cap came into 

force, and 2007, allowances traded between a low of about 120 $/short ton in 

2002 and a high of about 1600 $/short ton, with the 2005 spike being particularly 

dramaticr. Since there is no reason to believe that these conditions will alter over 

the life of a proposed standard, the challenge of forecasting prices is much more 

complex than a simple supply-demand balance might suggest. Also, note that any 

quantification of the benefit likely depends on the level of prices as well as their 

net change. To believe that a simple delta in the prices could be used to estimate 

the benefit is to believe that the same numerical reduction in price would result 

from the standard whether the prevailing trading price were $100 or $1,000 per 

short ton. 

The forecasting tool used for this TSD is the AEO2008 version of NEMS-BT and 

generates forecasts of both SO2 emissions and allowance prices. Unfortunately, this 

model was released before CAIR was overturned so its forecast enforces the tighter 

CAIR cap in the affected east of country, and does not represent current conditions. 

Given the timing of the CAIR ruling relative to the progress of this analysis, attaining 

projections without CAIR has not been possible. Nonetheless, as an indicative bounding 

case, the net changes in the average price were computed for the period 2012 to 2030 for 

standard size equipment at TSL 6 (the most stringent energy conservation standard 

considered in this analysis). The estimates represent an average of the various model 

simulations with different impact multipliers (see Appendix J for explanation of 

multipliers used) s

. 

For both PTAC and PTHP equipment, the specific results indicated about a -0.01 

percent change in the allowance price in the East region defined within the Electricity 

Market Module (EMM) of NEMS-BT. The Department considers this effect to be 

inconsequential relative to other elements in the benefits analysis, and given the 

significant effort that would be required to develop a refined estimate, the SO2 allowance 

price effect is not considered in this TSD. If future analysis suggests that the SO2 

allowance price effect is both significant and estimable using NEMS-BT, it may be added 

to supporting material. 

 

r

 sources of the historic SO2 allowance prices are http://www.epa.gov/airmarkets/progress/alprices.html, 

http://camddataandmaps.epa.gov/gdm/ s

 To be specific with regard to the method, for each simulation the arithmetic change in the allowance price 

between the standards case and the reference was first computed over the period 2012 to 2030. The 

percentage change was computed as this average change divided by the average allowance price in the 

reference case over the same period. After scaling to take into account the specific values of the impact 

multipliers across simulations (“100X”, “200X”, and “300X” values discussed in Appendix J), the resulting 

percentage changes were subsequently averaged over the simulations. The percentage change in the 

allowance price for the 200X case for PTAC equipment was slightly positive; this case was not used in the 

averaging in order to better reflect a bounding case for this equipment. 

16-23
16.3 WETLAND, ENDANGERED AND THREATENED SPECIES, AND 

CULTURAL RESOURCES 

DOE’s proposed action is not site-specific, nor would it affect land disturbance or 

use due to PTACs and PTHPs being installed in commercial buildings. Therefore, none 

of the proposed TSLs is expected to affect the quality of wetlands, or threatened or 

endangered species. Further, this action is not expected to impact cultural resources such 

as historical or archaeological sites. 

16.4 SOCIOECONOMIC IMPACTS 

DOE's analysis has shown that the increase in the first cost of purchasing a more 

efficient PTAC or PTHP at the proposed standard level is completely or nearly offset by 

a reduction in the life-cycle cost (LCC) of owning a more efficient piece of equipment. 

In other words, the customer will pay less operating costs over the life of the equipment 

even through the first cost increases. The complete analysis and its conclusions are 

presented in Chapter 8 of the TSD. 

For the sub-group of customers that are independent hotels, DOE determined that 

the average LCC impact is similar to that for the full sample of customers. Therefore, 

DOE concludes that the proposed action would have no significant socioeconomic 

impact. For a complete discussion on the LCC impacts on independent hotels, see 

Chapter 12 of the TSD. 

Table 16.4.1 shows the mean LCC savings for both the full sample of customers 

and independent hotels as the sub-group for standard-size and non-standard size PTACs 

and PTHPs. 

Table 16.4.1 Mean Life-Cycle Cost Savings for All Customers and Sub-Group, 

Standard Size PTACs and PTHPs 

Trial Standard Level 

Standard-Size 

PTACs and PTHPs TSL 1 TSL 2 TSL 3 TSL A TSL 4 TSL 5 TSL 6 

All Customers $6 $12 $11 $14 $14 $11 $7 

Independent Hotels $4 $9 $7 $10 $9 $6 $1

Non-Standard Size 

PTACs and PTHPs TSL 1 TSL 2 TSL 3 TSL 4 TSL 5 

All Customers $42 $43 $46 $50 $52 

Independent Hotels $36 $37 $38 $42 $43 

16-24
16.5 ENVIRONMENTAL JUSTICE IMPACTS 

According to Executive Order 12898 of February 11, 1994, “Federal Actions to 

Address Environmental Justice in Minority Populations and Low-Income Populations,” 

DOE is required to examine the effect of more stringent energy-efficiency standards on 

(1) small businesses that either manufacture or use PTAC or PTHP, (2) manufacturers of 

niche products related to PTAC or PTHP, and (3) small businesses operated by 

disadvantaged or minority populations. 

DOE identified small businesses as a sub-group that possibly could be 

disproportionately affected by PTAC and PTHP energy conservation standards. As 

described in the Life-Cycle Cost Subgroup Analysis, Chapter 11 of the TSD, DOE found 

that there was no disproportionately high and adverse human health or environmental 

effects on small businesses that would result from the proposed energy conservation 

standards. DOE believes that above conclusion also applies to minority populations. 

16.6 NOISE AND AESTHETICS 

Improvements in efficiency of PTAC and PTHP equipment is expected to result 

from changes in the choice of components and other design features. These changes are 

described in Chapter 5 of this TSD. Efficiency improvements result from improved heat 

exchanger designs using increased levels of coppers, and more efficient compressors. 

These design changes are not expected to change noise levels in comparison to 

equipment in today’s market. Equipment that is currently manufactured in the existing 

market that would meet the proposed standards is no louder than less efficient 

equipment. Changes to the design to improve the efficiency levels are not anticipated to 

affect the equipment’s aesthetics. 

16.7 SUMMARY OF ENVIRONMENTAL IMPACTS 

Table 16.7.1 and Table 16.7.2 summarize anticipated environmental impacts for 

each of the TSLs across all equipment types. Air quality impacts were modeled for each 

of the TSLs. The summary table shows cumulative changes in emissions for CO2, NOx, 

and mercury over the period 2012 to 2042. Cumulative CO2, NOx and Hg emissions 

show a decrease compared to the reference case. 

Upstream fuel cycle emission of CO2 and NOx are described but not quantified in 

section 16.2.6. The text describes potential reductions in fuel cycle emissions as 

percentage of decreases in power plant emissions. This qualitative approach suggests 

that upstream fuel cycle emissions would decrease and provides a sense for the 

magnitude of effects, however DOE does not report actual estimates of the effects. This 

approach does not address mercury emissions. 

Socioeconomic impacts are presented as changes in life cycle costs. No impacts 

are anticipated in the area of environmental justice; wetlands, endangered and threatened 

species, and cultural resources; or noise and aesthetics. 

16-25
Table 16.7.1 Environmental Impact Analysis Results Summary, Standard-Size 

PTACs and PTHPs 

Environmental Effects Referenc

e Case* 

Trial Standard Level 

1 2 3 A 4 5 6 

Cumulative Emission 

Reductions** 

 CO2 (Million metric tons) 208,728 -0.049 -0.081 -1.05 -1.06 -1.09 -1.68 -2.34 

 

 NOX (Thousand tons) 67,178 -0.04 to 

-0.094 

-0.07 to 

-1.64 

-0.08 to 

-2.02 

-0.09 to 

-2.13 

-0.09 to 

-2.25 

-0.13 to 

-3.17 

-0.18 to 

-4.34 

 

 Hg (tons) 547.9 0 to 

 -0.017 

0 to 

 -0.028 

0 to 

 -0.037 

0 to 

 -0.037 

0 to 

 -0.038 

0 to 

 -0.059 

0 to 

 -0.082 

Fuel-Cycle (Upstream) 

Emissions NA *** *** *** *** *** *** *** 

Wetlands, Endangered and 

Threatened Species, Cultural 

Resources 

NA None None None None None None None 

Socioeconomic Impacts - 

Weighted Mean LCC 

Savings† 

All Customers NA $6 $12 $11 $14 $14 $11 $7 

Independent Hotels NA $4 $9 $7 $10 $9 $6 $1 

Environmental Justice NA None None None None None None None 

Noise and Aesthetics NA None None None None None None None 

* The reference case values reflect total cumulative emissions and life cycle cost s in the absence of an energy conservation standard. 

** Cumulative total is over a time period from 2012 to 2042. Negative values refer to emission reductions. 

*** DOE does not report actual estimates of the effects of standards on upstream emissions, but section 16.2.5 provides a sense for the 

possible magnitude of effects. 

† Values refer to life-cycle cost savings over the equipment lifetime. 

16-26
Table 16.7.2 Environmental Impact Analysis Results Summary, Non-Standard 

PTACs and PTHPs 

Environmental Effects Reference 

Case* 

Trial Standard Level 

1 2 3 4 5 

Cumulative Emission 

Reductions** 

 CO2 (Million metric 

tons) 208,728 -0.012 -0.014 -0.018 -0.020 -0.029 

 NOX (Thousand tons) 67,178 -0.01 to 

 -0.23 

-0.01 to 

 -0.28 

-0.01 to 

-0.34 

-0.02 to 

 -0.40 

-0. 02 to 

 -0.55 

 Hg (tons) 547.9 0 to 

 -0.004 

0 to 

 -0.005 

0 to 

 -0.006 

0 to 

 -0.007 

0 to 

-0.010 

Fuel-Cycle (Upstream) 

Emissions NA *** *** *** *** *** 

Wetlands, Endangered and 

Threatened Species, 

Cultural Resources 

NA None None None None None 

Socioeconomic Impacts - 

Standard Size PTHP, 9000 

Btu/h Cooling Capacity, 

Mean LCC Savings† 

All Customers $42 $43 $46 $50 $52 $42 

Independent Hotels $36 $37 $38 $42 $43 $36 

Environmental Justice NA None None None None None 

Noise and Aesthetics NA None None None None None 

* The reference case values reflect total cumulative emissions and life cycle cost s in the absence of an energy conservation standard. 

** Cumulative total is over a time period from 2012 to 2042. Negative values refer to emission reductions. 

*** DOE does not report actual estimates of the effects of standards on upstream emissions, but section 16.2.5 provides a sense for the 

possible magnitude of effects. 

† Values refer to life-cycle cost savings over the equipment lifetime. 

16-27
16-28

REFERENCES 

1 . DOE. 2006. Environmental Assessment for Proposed Energy Conservation 

Standards for Distribution Transformers. DOE/EA-1565. Washington, D.C. 

2. DeLuchi, M. A. Emissions of Greenhouse Gases from the Use of Transportation 

Fuels and Electricity, Volume 2: Appendixes A-S. November, 1993. Argonne 

National Laboratory. Argonne, IL. Report No. ANL/ESD/TM-22-Vol.2. 

3. Energy Information Administration, Annual Energy Outlook 2008 (Revised Early 

Release) with Projections to 2030. 2008: Washington, DC. 

<http://www.eia.doe.gov/oiaf/aeo/> 

4. Intergovernmental Panel on Climate Change (IPCC). Climate Change 2007 – 

Impacts, Adaptation and Vulnerability, Contribution of Working Group II to the 

Fourth Assessment Report to the IPCC. < http://www.ipcc-wg2.org/> 

5. 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, 2006. 

Washington, DC. 

 <http://www.whitehouse.gov/omb/inforeg/2006_cb/2006_cb_final_report.pdf> 

6. Ted Gayer and Robert Hahn, “Designing Environmental Policy: Lessons from the 

Regulation of Mercury Emissions,” Regulatory Analysis 05-01 (AEI-Brookings 

Joint Center For Regulatory Studies) p. 31 (2004). A version of this paper was 

published in the Journal of Regulatory Economics in 2006. 

7. Tol, Richard S.J. The marginal damage costs of carbon dioxide emissions: an 

assessment of the uncertainties, Energy Policy 33 (2005) 2064-2074. 

8. Trasande, L., C. Schechter, K.A. Haynes, and P.J. Landrigan, “Applying Cost 

Analyses to Drive Policy that Protects Children,” 1076 ANN. N.Y. ACAD. SCI. 

911 (2006).