State CO2 Emission Rate Goals in EPA’s
Proposed Rule for Existing Power Plants
Jonathan L. Ramseur
Specialist in Environmental Policy
July 21, 2014
Congressional Research Service
7-5700
www.crs.gov
R43652

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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

Summary
On June 18, 2014, the Environmental Protection Agency (EPA) published a proposed rulemaking
that would establish guidelines for states to use when developing plans that address carbon
dioxide (CO2) emissions from existing fossil fuel-fired electric generating units. The proposal
creates CO2 emission rate goals—measured in pounds of CO2 emissions per megawatts-hours
(MWh) of electricity generation—for each state to achieve by 2030 and an interim goal to be
achieved “on average” between 2020 and 2029. EPA estimates that if the states achieve their
individual emission rate goals in 2030, the CO2 emissions from the electric power sector in the
United States would be reduced by 30% compared to 2005 levels.
This report discusses the methodology EPA used to establish state-specific CO2 emission rate
goals that apply to states’ overall electricity generation portfolio.
The emission rate goals do not apply directly to individual emission sources. EPA established the
emission rate goals by first determining each state’s 2012 emission rate baseline, which is
generally a function of each state’s portfolio of electricity generation in 2012. The resulting
baselines in each state vary considerably, reflecting, among other things, the different energy
sources used to generate electricity in each state.
To establish the emission rate goals, EPA applied four “building blocks” to the state baselines.
The four building blocks involve estimates of various opportunities for states to decrease their
emission rates:
• Building block 1: coal-fired power plant efficiency improvements;
• Building block 2: natural gas combined cycle displacement (NGCC) of more
carbon-intensive sources, particularly coal;
• Building block 3: increased use of renewable energy and preservation of existing
and under construction nuclear power; and
• Building block 4: energy efficiency improvements.
Building blocks 1 and 2 directly affect the CO2 emission rate at affected EGUs by factoring in
EGU efficiency improvements and opportunities to switch from high- to low-carbon power
generation. In contrast, building blocks 3 and 4 involve so-called “outside the fence”
opportunities that do not directly apply to electricity generation at affected EGUs.
The building blocks affect each state’s emission rate in different ways, depending on each state’s
specific circumstances. On average, block 1 has the smallest average impact, decreasing state
emission rate goals (compared to 2012 baselines) by a range of 0% to 6%.
Building block 2, on average, lowers rates by 13%, with a range of impacts from 0% to 38%
(compared to baseline). The largest rate changes are seen in states that have both coal-fired EGUs
and under-utilized NGCC plants. The smallest rate impacts are in states without any NGCC units
and states that already have relatively high NGCC utilization rates.
The under construction nuclear component of building block 3 only affects rates in three states,
but its rate impacts are considerable. An amount of at-risk nuclear generation was included in the
2012 baseline rates, lowering some state baselines by as much as 7%.
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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

The renewable energy component of block 3, on average, reduces emission rate baselines by 9%,
with a range from 2% to 33%. This block has a greater impact in states that use renewable energy
(not counting hydroelectric power) to generate a substantial percentage of their total electricity.
Building block 4 reduces rates, on average, by 13%, with a range of impacts between 4% and
37%. This range is a result of several factors, including (1) the contribution of in-state electricity
generation that comes from hydroelectric power or nuclear power; and (2) whether the state is a
net importer or net exporter of electricity.
The results of applying the four building blocks do not require or predict a particular outcome in a
state’s electricity generation profile. The emission rates are a function of EPA’s specific emission
rate methodology. States may choose to meet emission rate goals by focusing on one or more of
the building block strategies or through alternative approaches.

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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

Contents
Introduction ...................................................................................................................................... 1
2012 Emission Rate Baseline .......................................................................................................... 2
EPA Data Sources ...................................................................................................................... 2
Affected EGUs .......................................................................................................................... 2
2012 Emission Rate Equation ................................................................................................... 3
CO2 Emission Rate Goals ................................................................................................................ 5
Building Block 1—Coal-Fired Generation Efficiency Improvements ...................................... 6
Building Block 2—Increased Utilization of Natural Gas Combined Cycle Units .................... 7
Building Block 3—Renewable Energy and Nuclear Power ...................................................... 8
Renewable Energy ............................................................................................................... 9
Nuclear Energy .................................................................................................................. 13
Building Block 4—Energy Efficiency Improvements ............................................................. 14
Concluding Observations ............................................................................................................... 18

Figures
Figure 1. EPA’s 2012 State-Specific Emission Rate Baselines ........................................................ 5
Figure 2. EPA’s Proposed Regions in its Renewable Energy Methodology .................................... 9
Figure 3. Incremental Energy Efficiency Savings in 2012 by State .............................................. 16

Tables
Table 1. EPA’s “Adjusted” 2012 Baseline Emission Rate Equation ................................................ 4
Table 2. Illustration of Building Block 2 for Arizona’s Emission Rate Goal .................................. 8
Table 3. Renewable Energy Regions, Targets, and Growth Rates ................................................. 10
Table 4. Renewable Energy Generation ......................................................................................... 12
Table 5. Equation for CO2 Emission Rate Goals ........................................................................... 20
Table 6. 2012 State Emission Rate Baselines and Building Block Applications ........................... 21
Table 7. Application of EPA’s Building Blocks in Isolation .......................................................... 23

Contacts
Author Contact Information........................................................................................................... 26

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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

Introduction
On June 18, 2014, the Environmental Protection Agency (EPA) published in the Federal Register
a proposed rulemaking1 under Section 111(d) of the Clean Air Act.2 The proposal would establish
carbon dioxide (CO2) emission guidelines for states to use when developing plans that address
CO2 emissions from existing fossil fuel-fired electric generating units. For more background on
the statutory authority, history, and legal and administrative processes involving this rulemaking,
see CRS Report R43572, EPA’s Proposed Greenhouse Gas Regulations for Existing Power
Plants: Frequently Asked Questions, by James E. McCarthy et al.
The proposed rule establishes state-specific CO2 emission rate goals, measured in pounds of CO2
emissions per megawatt-hours (MWh) of electricity generation. This metric is generally described
as carbon intensity, which is a ratio of CO2 emissions per a unit of output, which is electric power
(MWh) in this context. EPA based its intensity goals on each state’s current portfolio of electricity
generation and various assumptions involving opportunities for states to decrease their carbon
intensity, including:
• coal-fired power plant efficiency improvements;
• natural gas combined cycle displacement of more carbon-intensive sources,
particularly coal;
• increased use of low-carbon sources, namely renewable energies like wind and
solar, and continued use of existing nuclear power generation; and
• energy efficiency improvements.
The proposal sets a final goal for each state3 for 2030 and an interim goal to be achieved “on
average” between 2020 and 2029.4 EPA estimates that if the states achieve their individual
emission rate goals in 2030, the CO2 emissions from the electric power sector in the United States
would be reduced by 30% compared to 2005 levels. However, the state emission rate goals are
based on a baseline year of 2012, not 2005.
This report discusses the methodology EPA used to establish the state-specific CO2 emission rate
goals. The first section explains the process by which EPA created state-specific 2012 emission
rate baselines. The emission rate equation EPA used to calculate the state baselines is provided at
the end of this section.
The second section discusses the four categories of emission reduction opportunities, described as
“building blocks” by EPA, that the agency used to determine the interim and 2030 emission rate
goals for each state. The emission rate equation that incorporates each building block is provided

1 79 Federal Register 34830, “Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric Utility
Generating Units,” June 18, 2014 (hereinafter EPA Proposed Rule).
2 42 U.S.C. §7411(d).
3 Vermont and the District of Columbia do not have emission rate goals, because they do not have electric generating
units affected by the proposal in their jurisdictions.
4 To satisfy the interim goal requirement, each state must demonstrate that the components of its plan would yield an
emission rate that is less than or equal to the interim goal. In addition, EPA proposes that states provide annual
performance updates to EPA during the interim period.
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at the end of this section. In addition, Table 6 at the end of this section lists the state-specific
2012 emission rate baselines, the final emission rate goals, and the incremental effects of
applying each of EPA’s building blocks to the 2012 baselines.
2012 Emission Rate Baseline
EPA’s first step in establishing the state-specific CO2 emission rate goals involved setting state-
specific baselines. The baseline is the starting point, from which future goals are measured. The
baseline year selection is an important issue for some states, because some states already have
regulations or policies that would directly (e.g., emissions cap) or indirectly (e.g., renewable
portfolio standards) reduce CO2 emissions. Some of these state requirements were in place well
before 2012.
EPA chose to use state-specific data from 2012 to establish the rate-based baselines, stating:
EPA chose the historic data approach as it reflected actual historic performance at the state
level. EPA chose the year 2012 as it represented the most recent year for which complete
data were available at the time of the analysis .... EPA also considered the possibility of
using average fossil generation and emission rate values over a baseline period (e.g., 2009 –
2012), but determined that there would be little variation in results compared to a 2012 base
year data set due to the rate-based nature of the goal.5
EPA Data Sources6
EPA used its Emissions & Generation Integrated Resource Database (eGRID) to provide the
underlying data for the vast majority of the inputs the agency used to generate state emission
rates. According to EPA, “eGRID integrates many different data sources on power plants and
power companies, including, but not limited to: the EPA, the Energy Information Administration
(EIA), the North American Electric Reliability Corporation (NERC), and the Federal Energy
Regulatory Commission (FERC).”7 In addition, EPA used its National Electric Energy Data
System (NEEDS) to identify nuclear and NGCC plants that were not operating in 2012 but are
under construction.
Affected EGUs
The 2012 state baselines are based on CO2 emissions from electric generating units (EGUs) that
are addressed in the proposal. These units are called “affected EGUs.” The terminology in this
proposal differs from other air pollutant regulations that apply directly to “covered sources” or
“regulated entities.” The emission rate goals described below do not apply directly to individual
power plants, but to the state’s overall electricity generation portfolio.

5 See EPA, Goal Computation Technical Support Document, June 2012, at http://www2.epa.gov/carbon-pollution-
standards/clean-power-plan-proposed-rule-technical-documents.
6 For more details, see EPA, “Goal Computation Technical Support Document,” June 2014, at
http://www2.epa.gov/carbon-pollution-standards/clean-power-plan-proposed-rule-technical-documents.
7 EPA, Technical Support Document, GHG Abatement Measures, at http://www2.epa.gov/carbon-pollution-
standards/clean-power-plan-proposed-rule-technical-documents.
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In general, an affected EGU is a fossil fuel-fired unit that was in operation or had commenced
construction as of January 8, 2014, has a generating capacity above a certain threshold, and sells a
certain amount of its electricity generation to the grid. The specific criteria include the following:
1. has a base load rating greater than 73 MW;
2. combusts fossil fuel for more than 10% of its total annual heat input; and
3. sells the greater of 219,000 MWh per year8 or one-third of its potential electrical
output to a utility distribution system.9
Based on 2012 data provided by EPA, the “affected EGU” definition applies to over 3,100 EGUs
at 1,508 facilities throughout the United States.10 The number of “affected” power plant facilities
range by state, from 2 EGUs in Idaho to 115 EGUs in Texas, with a median number of 19.
Net Energy Output Versus Gross Output
In its proposed rule, EPA measures energy generation from affected EGUs in terms of net output rather than gross
output. Gross output is the total amount of electricity (and/or useful thermal output)11 that is produced at the
generator terminal. Some of this gross output is used on-site to operate equipment at the EGU (e.g., pumps, fans, or
pol ution control devices). Net output equals gross output minus the amount of energy used on-site, thus capturing
only the electricity that is delivered to the transmission grid.
EPA explains that a net output measure would account for reduction opportunities in on-site energy use, which
would not be captured using a gross output measure.12 This would provide an incentive for on-site energy efficiency
improvements. However, EPA notes that its proposed rule for new EGUs measures gross generation. The agency is
requesting comment on the use of net generation for existing EGUs.
2012 Emission Rate Equation
EPA constructed the 2012 state baselines using CO2 emissions and electricity generation data
from the affected EGUs and several additional electricity generation categories described below.
First, EPA grouped the affected EGUs into different categories: coal-fired steam generation; oil
and gas (OG) steam generation; natural gas combined cycle (NGCC) generation; and “other”
affected EGUs. This last grouping includes fossil sources, such as integrated gasification
combined cycle (IGCC) units, high utilization combustion turbine units, and applicable thermal
output at cogeneration units. EPA separated the data from these units because they are not part of
the building block applications described below.13 On a national basis, the “other” category

8 This generally equates to a 25 MW unit (25 MW * 8,760 hours = 219,000 MWh).
9 This is measured on an annual basis for steam units and IGCC units and on a three-year rolling average basis for
stationary combustion turbine units. For more information, the proposed rule references a discussion in the proposed
rule for new sources at 79 Federal Register 1430 (January 8, 2014).
10 CRS calculations using EPA’s “Technical Support Document: Goal Computation-Appendix 7” Excel spreadsheet, at
http://www2.epa.gov/carbon-pollution-standards/clean-power-plan-proposed-rule-technical-documents-spreadsheets.
11 For the most part, energy generation refers to electricity, but some EGUs, namely combined heat and power
facilities, also produce heat (referred to as “useful thermal output”) that can be used on-site for other industrial
processes.
12 See EPA Proposed Rule, p. 34894.
13 According to EPA, “IGCCs represent a very small sample size of three operating plants and have a different
utilization pattern and different capital cost profile than NGCCs that result in a different set of redispatch economics.
Likewise, high utilization [combustion turbines] that may be covered by the rule are generally less efficient and have
higher emission rates than NGCCs, and are therefore generally less cost effective for redispatch purposes [i.e., building
(continued...)
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accounts for approximately 1% of total U.S. electricity generation and CO2 emissions.14 And for
the vast majority of states, these sources have minimal impacts on emission rates.
To establish each state’s 2012 baseline, EPA calculated the pounds of CO2 generated from
affected EGUs in each state (the numerator in the Table 1 equation)15 and then divided that sum
by the electricity generated (the denominator in the Table 1 equation) from affected EGUs in
each state. This yields an emission rate measured in pounds (lbs.) of CO2 per megawatt-hours
(MWh) of electricity generation. EPA described this result as the “unadjusted” emission rate.
To establish the final, “adjusted” 2012 baseline for each state, EPA added two elements to the
denominator of the emission rate equation (in Table 1): “at-risk” nuclear power (discussed below)
and renewable energy generation. The addition of these elements produced the “adjusted”
emission rate equation, which is used to generate the 2012 baseline emission rate for each state.
The adjusted emission rate equation is provided below:
Table 1. EPA’s “Adjusted” 2012 Baseline Emission Rate Equation




coal generation
OG generation
NGCC generation
“Other”

X
X
X
+
+
+ CO

2

coal emission
OG emission
NGCC emission
emissions
rate
rate
rate
2012
Emission =
Rate
“Other”
“At-
Renewable
coal generation
+ OG generation
+ NGCC generation
+ generation + Risk”
+ energy
Nuclear
generation
Notes: OG = oil and gas; NGCC = natural gas combined cycle; “other” generation includes fossil fuel EGUs,
such as integrated gasification combined cycle (IGCC) units, high utilization combustion turbine units, and
applicable thermal output at cogeneration units; “at-risk” nuclear includes 5.8% of a state’s nuclear power
capacity; renewable energy includes solar, wind, geothermal, wood and wood-derived fuels, other biomass, but
not hydroelectric power.
For the “at-risk” nuclear power element, EPA assumes that under a business-as-usual scenario
some amount of existing nuclear power will be unavailable for use in the near future. Using
projections from EIA, EPA determined that 5.8% of total U.S. nuclear power capacity was at risk
of being retired in the near future.16 EPA used this percentage value to estimate at-risk nuclear
power (in MWh) for each state with operating nuclear units in 2012.17 According to EPA, this
projected outcome is due to a “host of factors –increasing fixed operation and maintenance costs,

(...continued)
block 2].” See EPA, “Goal Computation Technical Support Document,” June 2014, at http://www2.epa.gov/carbon-
pollution-standards/clean-power-plan-proposed-rule-technical-documents.
14 CRS calculation based on 2012 data provided in EPA’s technical document spreadsheets.
15 At first glance, the numerator appears to have extraneous information. For example, it could simply contain pounds
of CO2 from the various categories, instead of generation and emission rate data (which ultimately yields pounds).
16 See EPA’s Technical Support Document, GHG Abatement Measures.
17 For states that use a greater portion of nuclear power as part of their electricity generation portfolio, adding this
element to the denominator has a more pronounced effect. For example, South Carolina generated the highest
percentage (53%) of its electricity generation from nuclear power in 2012. South Carolina’s unadjusted emission rate
decreased by 7% with the addition of at-risk nuclear power to the emission rate equation (CRS calculations, using EIA
electricity generation, by source and state, at http://www.eia.gov/electricity/data.cfm#generation).
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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

relatively low wholesale electricity prices, and additional capital investment associated with
ensuring plant security and emergency preparedness.”
In addition, EPA added each state’s renewable energy electricity generation (in MWh) from 2012
into the state baseline calculation.18 As discussed below, renewable energy potential plays an
important role in determining EPA’s emission rate interim and final goals. Including renewable
energy in the state baseline rates allows for a more appropriate comparison between the 2012
baseline and interim and final rate goals.
Applying the above equation to each state’s specific circumstances yields a range of emission rate
baselines, as illustrated in Figure 1.
Figure 1. EPA’s 2012 State-Specific Emission Rate Baselines
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CO2 Emission Rate Goals
In its proposed rule, EPA identified four categories of CO2 emission reduction strategies that
states could employ to reduce the states’ overall CO2 emission rates. EPA proposed that the
combination of these four strategies—described as “building blocks”—represents the “best
system of emission reduction...adequately demonstrated,” a key determination pursuant to CAA
Section 111(d).19 Using the state-specific 2012 baseline data as its starting point, EPA applied the
four building blocks to establish CO2 emission rate goals for each state.

18 For reasons discussed below, hydropower is not included in the 2012 renewable energy baseline.
19 See CRS Report R43572, EPA’s Proposed Greenhouse Gas Regulations for Existing Power Plants: Frequently
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Building blocks 1 and 2 directly affect the CO2 emission rate at affected EGUs by factoring in
efficiency improvements at EGUs and opportunities to switch from high- to low-carbon power
generation. In contrast, blocks 3 and 4 involve so-called “outside the fence” opportunities that do
not directly apply to electricity generation at affected EGUs. These blocks decrease the states’
overall CO2 emission rates by (1) increasing the use of low- or zero-carbon electricity generation
and (2) reducing consumer demand for electricity through energy efficiency improvements.
The equation for the 2030 emission rate goals, which includes the application of all four building
blocks, is provided at the end of this section. Compared to the 2012 baseline emission rate
equation, building blocks 3 and 4 add more elements to the equation’s denominator. In its
proposal, EPA explained:
A goal expressed as an unadjusted output-weighted-average emission rate would fail to
account for mass emission reductions from reductions in the total quantity of fossil fuel-fired
generation associated with state plan measures that increase low- or zero-carbon generating
capacity [e.g., renewable portfolio standards] or demand-side energy efficiency.
Accordingly, under the proposed goals, the emission rate computation includes an
adjustment designed to reflect those mass emission reductions .... Mathematically, this
adjustment has the effect of spreading the measured CO2 emissions from the state’s affected
EGUs over a larger quantity of energy output, thus resulting in an adjusted mission rate
lower than the unadjusted emission rate.
The following discussion describes each of these building blocks and their relative contributions
to the state-specific emission rate goals.
Building Block 1—Coal-Fired Generation Efficiency Improvements
Building block 1 applies heat rate20 (i.e., efficiency) improvements to coal-fired, steam EGUs.
EPA maintains that these EGUs are “less efficient at converting fuel into electricity than is
technically and economically possible.”21 Almost all of the existing coal-fired EGUs are
considered steam EGUs. A small percentage of coal-fired EGUs are integrated gasification
combined cycle (IGCC) units, but the proposed heat rate improvements in building block 1 do not
apply to these units. EPA is seeking comment on whether the agency should include heat rate
improvements at other fossil-fuel EGUs as part of its emission rate calculations.
Potential heat rate improvements include the adoption of operation and maintenance best
practices and equipment upgrades. EPA determined that a combination of these potential options
could improve coal-fired EGU heat rates by 6%. A reduction in the heat rate leads to a
proportional reduction in CO2 emissions, because CO2 emissions are directly related to the
amount of fuel consumed. Therefore, building block 1 reduces each state’s CO2 emissions rate
(pounds of CO2 per MWh) for coal-fired affected EGUs by as much as 6%.22

(...continued)
Asked Questions, by James E. McCarthy et al.
20 Heat rate is the efficiency of conversion from fuel energy input to electrical energy output often expressed in terms of
BTU per kiloWatt-hour.
21 EPA’s Technical Support Document, GHG Abatement Measures, at http://www2.epa.gov/carbon-pollution-
standards/clean-power-plan-proposed-rule-technical-documents.
22 For a further discussion, see CRS Report R43621, EPA’s Proposed Greenhouse Gas Regulations: Implications for
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For example, if a state’s coal-fired affected EGUs averaged 2,000 pounds of CO2 emissions per
MWh in 2012, building block 1 could decrease this rate to 1,880 pounds CO2 per MWh. This
lowers one of the elements (“coal emission rate”) in the numerator of the emission rate equation
(Table 5), but has no effect on the denominator.
As indicated in Table 6, building block 1 decreases state emission rate goals (compared to 2012
baselines) by a range of 0% to 6%. The greater rate impacts are seen in states that have a
relatively high percentage of coal-fired electricity in their electricity generation portfolio.
Building Block 2—Increased Utilization of Natural Gas Combined
Cycle Units
Building block 2 lowers a state’s CO2 emission rate (pounds of CO2 per MWh) from the baseline
by shifting a state’s electricity generation from higher-carbon units, such as coal-fired EGUs, to
lower-carbon NGCC units.23 The carbon intensity of different types of EGUs can vary
considerably. According to EPA,24 the 2012 average CO2 emission rates by unit type category
were the following:
• Coal steam units = 2,220 lbs. CO2/MWh
• Oil and natural gas steam units = 1,463 lbs. CO2/MWh
• NGCC units = 907 lbs. CO2/MWh
As electricity demand increases during the day, system operators or regional transmission
organizations call into service (“dispatch”) additional power plants to meet the electricity needs.
When electricity demand decreases, these additional units are taken off-line. In general, coal-fired
EGUs are dispatched before NGCC units, because coal-fired plants take hours or days to ramp up
to their design capacity and they have traditionally been cheaper to operate than most other
sources.
EPA concluded that there is “significant potential for re-dispatch” from steam EGUs to NGCC
units.25 The agency estimated that, in aggregate, NGCC units provided about 46% of their total
generating capacity in 2012. This measure is called the capacity factor. Based on its analysis, EPA
determined that a state’s capacity factor for its NGCC units could be increased to 70%. Building
block 2 uses the 70% capacity factor to increase the utilization of NGCC units and
correspondingly decrease generation from more carbon intensive EGUs.
As an example, Table 2 illustrates the application of building block 2 for Arizona. In 2012,
NGCC units in Arizona generated 26.8 million MWh of electricity, which represented
approximately 27% of the total NGCC nameplate capacity (11,202 MW) in the state.26 Under

(...continued)
the Electric Power Sector, by Richard J. Campbell.
23 For a further discussion, see CRS Report IN10089, The Role of Natural Gas in EPA’s Proposed Clean Power Plan,
by Richard K. Lattanzio.
24 EPA’s Technical Support Document, GHG Abatement Measures.
25 EPA’s Technical Support Document, GHG Abatement Measures.
26 If the state had NGCC under construction, this generating capacity would also be included.
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building block 2 methodology, the increase in NGCC generation is capped at the lower of two
ceilings: 70% of the nameplate capacity or the total generation from coal and OG steam EGUs
and NGCC units in 2012. Applying the 70% NGCC capacity factor would increase NGCC
generation from 26.8 million MWh to 68.9 million MWh,27 well above the total generation from
all units in 2012 of 52.1 million MWh. Therefore, NGCC generation increases to 52.1 million
MWh, the total generation from fossil fuel units in 2012. Applying block 2 methodology, the
increased NGCC generation replaces generation from coal and OG steam EGUs, decreasing their
generation to zero.
As Table 2 indicates, building block 2 has a substantial effect on Arizona’s emission rate,
reducing it by 42%. Note that the results of applying building block 2 do not require or predict a
particular outcome in a state’s electricity generation profile. The results are a function of the
emission rate methodology. States may choose to meet their emission rate goals through
alternative approaches.
Table 6 shows the effect that building blocks 1-2 have on all of the 2012 state emission rate
baselines.
Table 2. Illustration of Building Block 2 for Arizona’s Emission Rate Goal

2012 Baseline
After Building Block 2
Coal steam generation
24.3 million MWh
0
OG steam generation
1.0 million MWh
0
NGCC generation
26.8 million MWh
52.1 million MWh
Total generation
52.1 million MWh
52.1 million MWh



NGCC capacity factor
27%
53%
Emissions Rate
1,453 lbs. CO2/MWh
843 lbs. CO2/MWh



NGCC nameplate capacity = 11,202 MW


Source: Prepared by CRS; data from EPA Proposed Rule, technical support documents and spreadsheets, at
http://www2.epa.gov/carbon-pol ution-standards/clean-power-plan-proposed-rule-technical-documents.
Building Block 3—Renewable Energy and Nuclear Power
Building block 3 factors in additional electricity generation from low- or zero-carbon emitting
sources, including renewable energy and nuclear power. Both types of generation are added to the
denominator for the emission rate equation (see Table 5 at the end of this section), but the
numerator is unchanged. The methodologies for incorporating these categories of electricity
generation are very different, thus they are discussed separately below.

27 11,202 MW * 8,784 hours (in 2012, a leap-year) * 0.7 = 68.9 million MWh.
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Renewable Energy
Building block 3 projects annual renewable energy (RE) increases for each state. Current RE use
varies by states and the potential to utilize different types of renewable energy sources—wind,
solar, geothermal—varies by geographic location. To “account for similar power system
characteristics as well as geographic similarities in [renewable energy] potential,”28 As illustrated
in Figure 2, EPA placed each state into one of six regions (Alaska and Hawaii have individual
targets). EPA determined a RE 2030 target for each region based on an average of existing RE
targets that are required by states in the relevant region.29 Then, EPA calculated an annual growth
rate for each region that would allow each region to reach its specific target by 2030.
Figure 2. EPA’s Proposed Regions in its Renewable Energy Methodology

Source: Figure 4-3 from EPA, Technical Support Document, GHG Abatement Measures.
Table 3 lists the six regions and their states, the regional targets, and the average annual growth
rates for each region. The regional targets range from 10% to 25%, and the growth rates range
from 6% to 17%. As the table indicates, a region can have a relatively high regional target (e.g.,
the West region’s target of 21%) but have a relatively low growth rate (6% in the West region).

28 Unofficial proposed rule, p. 195.
29 As of March 2013, 29 states (and the District of Columbia) have established renewable portfolio standards (RPS),
requiring retail electricity suppliers to supply a minimum percentage or amount of their retail electricity load with
electricity generated from eligible sources of renewable energy, as defined by the state. An additional nine states have
voluntary goals. See the Database of State Incentives for Renewables and Efficiency, at http://www.dsireusa.org/.
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Conversely, a state can have a relatively low target (10% in the Southeast region) and a relatively
high growth rate (13% in the Southeast region). These outcomes are a function of EPA’s
methodology. For instance, the West region’s growth rate is relatively low, because some of the
states—namely California, which accounts for 28% of the region’s total electricity generation—
are more than halfway toward the regional goal. In contrast, the states in the Southeast are starting
with relatively low percentages (0% to 3%) of RE generation in 2012, which accounts for the
relatively high growth rate needed to achieve their regional target.
Table 3. Renewable Energy Regions, Targets, and Growth Rates
Average Annual
Region States
Regional
Target
Growth Rate
East Central
Delaware, District of Columbia, Maryland, New Jersey, Ohio,
16% 17%
Pennsylvania, Virginia, and West Virginia
North Central
Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, North
15% 6%
Dakota, South Dakota, and Wisconsin
Northeast
Connecticut, Maine, Massachusetts, New Hampshire, New York,
25% 13%
Rhode Island, and Vermont
South Central
Arkansas, Kansas, Louisiana, Nebraska, Oklahoma, and Texas
20%
8%
Southeast
Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina,
South Carolina, and Tennessee
10% 13%
West
Arizona, California, Colorado, Idaho, Montana, Nevada, New
Mexico, Oregon, Utah, Washington, and Wyoming
21% 6%
Alaska
10% 11%
Hawaii
10% 8%
Source: Prepared by EPA; data from EPA, Technical Support Document, Greenhouse Gas Abatement Measures.
Notes: Although Vermont does not have an emission rate goal, EPA included Vermont’s RE generation when
the agency determined the annual growth rate for the Northeast region. If Vermont’s RE generation is excluded,
the annual growth rate increases slightly, but remains at 13%.
EPA applies the region-specific, annual growth rate to each state’s RE generation in 2012 to
estimate annual RE generation for each state from 2017 through 2030.30 If a state’s RE use equals
or exceeds its 2030 regional target, the state’s RE use is held constant at the level that matches its
regional target.
The 2012 RE baseline does not include hydroelectric generation.31 According to EPA:
Inclusion of this generation in current and projected levels of performance would distort the
proposed approach by presuming future development potential of large hydroelectric
capacity in other states. Because RPS [renewable portfolio standard] policies were
implemented to stimulate the development of new RE generation, existing hydroelectric

30 Further details about this methodology are in a technical support document for the proposed rule, GHG Abatement
Measures, Chapter 4, at http://www2.epa.gov/carbon-pollution-standards/clean-power-plan-proposed-rule-technical-
documents.
31 According to EPA, “
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facilities are often excluded from RPS accounting. No states are expected to develop any
new large facilities.32
Although EPA’s determination of regional RE targets does not explicitly account for opportunities
to build new hydroelectric facilities,33 states could use increased hydroelectric power generation
in the future to lower their emission rate.
Table 4 applies EPA’s methodology and depicts the states’ RE levels in 2012, total electricity
generation in 2012, and the percentage of electricity generation from renewable sources in 2012
and 2030. The last column measures the projected RE generation in 2030 against the total
electricity generation in 2012.
EPA’s RE building block 3 methodology yields the following results:
• About half of the states would not reach their region-specific goals by 2030; the
other half would reach the region-specific goals. Some of these states reached
their goals in the early years. In general, the percentage of electricity generated
from renewable sources in these states was relatively high in the baseline year
(2012);
• Five states—Iowa, Maine, Minnesota, North Dakota, and South Dakota—
matched or exceeded their regional RE targets in 2012, so the estimated future
RE generation (for the purposes of the emission rate calculations) in these states
actually decreases to match their regional targets. Arguably, this outcome
artificially lowers the emission rate targets for these states and EPA specifically
asks for comment on whether the calculations should include a RE floor based on
2012 generation; and
• The impact of building block 3 varies considerably by states. Not counting the
states that meet or exceed their targets in 2012, some states increase their
percentages of RE generation by 2%; others increase their percentages by over
18%. These different impacts are reflected in Table 6, which shows the emission
rate change after applying blocks 1-3.

32 EPA, Technical Support Document, Greenhouse Gas Abatement Measures, pp. 4-5.
33 EPA, Technical Support Document, Greenhouse Gas Abatement Measures, pp. 4-5.
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Table 4. Renewable Energy Generation
States Grouped in Their Renewable Energy Regions
2012 RE Generation
2012 Total Electricity
Percent of RE
Percent of RE
State
(MWh)
Generation (MWh)
Generation in 2012
Generation in 2030
Region: East Central – Target 16% – Annual Growth Rate 17%
Delaware 131,051

8,633,694
2%
12%
Maryland 898,152

37,809,744
2%
16%
New Jersey
1,280,715
65,263,408
2%
16%
Ohio 1,738,622

29,745,731
1%
11%
Pennsylvania 4,459,118

23,419,715
2%
16%
Virginia 2,358,444

70,739,235
3%
16%
West Virginia
1,296,563
73,413,405
2%
14%
Region: North Central –Target 15% – Annual Growth Rate 6%
Illinois 8,372,660

197,565,363
4%
9%
Indiana 3,546,367

114,695,729
3%
7%
Iowa 14,183,424

56,675,404
25%
15%
Michigan 3,785,439

108,166,078
3%
7%
Minnesota 9,453,871

52,193,624
18%
15%
Missouri 1,298,579

91,804,321
1%
3%
North Dakota
5,280,052
36,125,159
15%
15%
South Dakota
2,914,666
12,034,206
24%
15%
Wisconsin 3,223,178
63,742,910
5%
11%
Region: Northeast – Target 25% – Annual Growth Rate 13%
Connecticut 666,525

36,117,544
2%
9%
Maine 4,098,795

14,428,596
28%
25%
Massachusetts 1,843,419

36,198,121 5%
24%
New Hampshire
1,381,285
19,264,435
7%
25%
New York
5,192,427
135,768,251
4%
18%
Rhode Island
101,895
8,309,036
1%
6%
Vermont 465,169
6,569,670
7%
25%
Region: South Central – Target 20% – Annual Growth Rate 8%
Arkansas 1,660,370

65,005,678
3%
7%
Kansas 5,252,653

44,424,691
12%
20%
Louisiana 2,430,042

103,407,706
2%
7%
Nebraska 1,346,762

34,217,293
4%
11%
Oklahoma 8,520,724

77,896,588
11%
20%
Texas 34,016,697

429,812,510
8%
20%
Region: Southeast – Target 10% – Annual Growth Rate 13%
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2012 RE Generation
2012 Total Electricity
Percent of RE
Percent of RE
State
(MWh)
Generation (MWh)
Generation in 2012
Generation in 2030
Alabama 2,776,554

152,878,688
2%
9%
Florida 4,523,798

221,096,136
2%
10%
Georgia 3,278,536

122,306,364
3%
10%
Kentucky 332,879

89,949,689
0.4%
2%
Mississippi 1,509,190

54,584,295
3%
10%
North Carolina
2,703,919
116,681,763
2%
10%
South Carolina
2,143,473
96,755,682
2%
10%
Tennessee 836,458

77,724,264
1%
6%
Region: West – Target 21% – Annual Growth Rate 6%
Arizona 1,697,652

95,016,925
2%
4%
California 29,966,846

199,518,567
15%
21%
Colorado 6,192,082

52,556,701
12%
21%
Idaho 2,514,502

15,499,089
16%
21%
Montana 1,261,752

27,804,784
5%
10%
Nevada 2,968,630

35,173,263
8%
18%
New Mexico
2,573,851
22,894,524
11%
21%
Oregon 7,207,229

60,932,715
12%
21%
Utah 1,099,724

36,312,527
3%
7%
Washington 8,214,350

116,835,474
7%
15%
Wyoming 4,369,107
49,588,606
9%
19%





Alaska 39,958
6,946,419
1%
2%
Hawai 924,815
10,469,269
9%
10%
Source: Prepared by CRS; data from EPA, Technical Support Document, Greenhouse Gas Abatement
Measures, which uses data from EIA, “Net Generation by State by Type of Producer by Energy,” at
http://www.eia.gov/electricity/data/state/.
Notes: RE generation includes solar, wind, geothermal, wood and wood-derived fuels, other biomass, but not
hydroelectric power. The “total electricity generation” data include generation from multiple sources, including
both affected and non-affected fossil-fired EGUs, the above renewable energy sources and hydroelectric power.
The column labeled “Percent of RE Generation in 2030” measures the projected RE generation (MWh) in 2030
compared to the total MWh of electricity generated in 2012.
Although Vermont does not have an emission rate goal, EPA included Vermont’s RE generation when the agency
determined the annual growth rate for the Northeast region. If Vermont’s RE generation is excluded, the annual
growth rate increases slightly, but remains at 13%.
Nuclear Energy
The second part of building block 3 involves nuclear power generation. EPA includes both “at-
risk” and “under construction” nuclear power in the denominator of the emission rate equation
(see Table 5 at the end of this section). As discussed above, the “at-risk” nuclear power, which
exists in 30 states, was factored into the state 2012 baseline emission rates. Thus, its inclusion in
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the emission rate goal equation has no effect on the emission rate compared to the 2012
baseline.34 However, its inclusion in the 2012 baseline equation was unique: it was the only part
of the baseline equation that projected future activity (i.e., loss of nuclear power capacity). Thus,
if states do not maintain their existing nuclear generation, their emission rates will increase (all
else being equal). Including at-risk nuclear generation in the baseline equation denominator was
one of EPA’s “adjustments.” The at-risk nuclear generations lowered the (unadjusted) baselines in
some states by as much as 7%, thus having a stronger impact that building block 1.
In addition to the “at-risk” nuclear power, EPA added projected electricity generation from
nuclear power units that are currently under construction. EPA identified five under-construction
nuclear units at three facilities in Georgia, South Carolina, and Tennessee. The estimated electric
generation from these units and their percentage contribution to the state’s total electricity
generation in 2012 are listed below:
• Georgia: approximately 17 million MWh (14% of total electric generation in
2012)
• South Carolina: approximately 17 million MWh (18% of total electric generation
in 2012);
• Tennessee: approximately 9 million MWh (11% of total electric generation in
2012).
Including the estimated generation from these anticipated units in the emission rate equation
substantially lowers the emission rates of these three states (Table 6). If these anticipated units do
not complete construction and enter service, these states would likely have more difficulty
achieving their emission rate goals.
Building Block 4—Energy Efficiency Improvements
The fourth building block reduces state emission rates by including avoided electricity generation
that results from projected energy efficiency (EE) improvements. These EE improvements are
described as “demand-side,” because they would seek to reduce the demand for electricity from
end-users, such as factories, office buildings, and homes. EPA estimated the amount of decreased
electricity generation in each state that would result from EE activities and added the avoided
MWh to the denominator of the emission rate equation (Table 5).
Demand-side EE activities can involve a range of practices in the residential, commercial, and
industrial sectors. According to EPA, “every state has established demand-side energy efficiency
policies.”35 However, these policies cover a wide range of activities, and, as discussed below,
their effectiveness varies. EPA states that the “most prominent and impactful” EE policies in most
states are those that the drive development and funding of EE programs and building codes.36
To estimate the avoided electricity generation, EPA first determined the “best practices”
performance target for all states. Using data from EIA,37 EPA calculated each state’s incremental

34 The same MWh value is added to the denominator in both equations, having no impact on the emission rate goals.
35 EPA Proposed Rule, p. 34871.
36 EPA, Technical Support Document, Greenhouse Gas Abatement Measures.
37 EPA used data from EIA Form 861, which includes retail electricity sales and incremental electricity savings from
(continued...)
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EE savings as a percentage of retail electricity sales. According to EPA, “incremental savings
(also known as first-year savings) represent the reduction in electricity use in a given year
associated with new EE activities in that same year.” As Figure 3 illustrates, the states’ 2012
incremental EE savings ranged from 0% to 2.19%.
In addition to the three states—Vermont, Maine, and Arizona—that achieved EE savings greater
than 1.5% (Figure 3), EPA concluded that nine other states are expected to reach this annual level
of performance by 2020.38 Based on these observed and expected achievements, EPA determined
that the “best practices” performance target for all states should be 1.5%. Figure 3 depicts this
performance target as a red line. EPA explained:
[The best practices scenario] does not represent an EPA forecast of business-as-usual
impacts of state energy efficiency policies or an EPA estimate of the full potential of end-use
energy efficiency available to the power system, but rather represents a feasible policy
scenario showing the reductions in fossil fuel-fired electricity generation resulting from
accelerated use of energy efficiency policies in all states consistent with a level of
performance that has already been achieved or required by policies (e.g., energy efficiency
resource standards) of the leading states.39
Similar to the RE methodology described above, EPA’s calculations assume that the EE
component of the rate equation begins in 2017, and states would start that year at the EE
incremental saving levels achieved in 2012 (Figure 3). EPA points out that EE improvements
made between 2012 and 2017 would count toward achieving a state’s emission rate target.
However, if a state were to decrease its actual EE performance prior to 2017, the state would face
a more difficult effort (all else being equal) in achieving its emission rate goal, as its 2017 EE
starting point would be based on its (higher) 2012 EE performance level.


(...continued)
energy efficiency, available at http://www.eia.gov/electricity/data/eia861/index.html.
38 EPA, Technical Support Document, Greenhouse Gas Abatement Measures.
39 EPA Proposed Rule, p. 34872.
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Figure 3. Incremental Energy Efficiency Savings in 2012 by State
Compared to EPA’s Best Practices Level
Vermont
Maine
Arizona
California
Minnesota
Oregon
Pennsylvania
Wisconsin
Iowa
Connecticut
Michigan
Massachusetts
Washington
New York
Illinois
Maryland
Ohio
Colorado
Idaho
Rhode Island
Utah
Montana
New Mexico
Indiana
Nevada
EPA Best
New Hampshire
North Carolina
South Carolina
Practices Level
Tennessee
Nebraska
Florida
Kentucky
Oklahoma
Texas
West Virginia
Georgia
Wyoming
South Dakota
Missouri
Arkansas
Mississippi
North Dakota
Alabama
Hawaii
Virginia
New Jersey
Kansas
Alaska
Louisiana
Delaware
0.00%
0.50%
1.00%
1.50%
2.00%
2.50%
Incremental Energy Efficiency Savings as a
Percentage of Electricity Sales

Source: Prepared by CRS; data from EPA, Technical Support Document, Greenhouse Gas Abatement
Measures. EPA used data from EIA Form 861, which includes retail electricity sales and incremental electricity
savings from energy efficiency, available at http://www.eia.gov/electricity/data/eia861/index.html.
Notes: Although Vermont does not have an emission rate goal, EPA included its EE performance in its best
practice analysis.
The next determination made by EPA was the pace at which states, starting in 2017, would
annually increase their EE incremental performance. Based on its analysis of historical EE
performance increases and future requirements for some states, EPA chose an annual increase of
0.2%, which it deemed as a “conservative” value.
EPA assumed that each state would increase its incremental EE performance by 0.2% each year,
starting in 2018, until it reached the best practices, incremental target of 1.5%. EPA projects that a
small number of states would achieve this level in 2017, with the rest of the states reaching this
level by 2025. Once this level is achieved, EPA assumed the states could sustain that incremental
performance level through 2030.
Next, EPA estimated the cumulative savings that each state would achieve through its annual,
incremental EE efforts. In contrast to incremental savings, which measure EE improvements
made in one specific year, cumulative savings include the aggregate impacts of EE improvements
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made in prior years. This raises the question: how many years are counted in the cumulative
savings tally? For instance, the installation of a high-efficiency appliance may yield EE savings
for the life of the appliance (e.g., 10-15 years), referred to as its “measure life.” Other
improvements (e.g., home insulation, building codes) may provide savings for twenty years or
more. Based on its analysis of various studies, EPA determined the average measure life for an
EE portfolio would be 10 years. However, in its EE methodology, EPA distributed the decline in
EE savings over 20 years, instead of having 10 years of savings and then dropping to zero at year
11. Both approaches lead to the same overall EE savings, but EPA’s approach spreads the savings
over a longer period of time.
EPA used the above inputs to estimate cumulative EE savings, as a percentage of retail sales, for
each state for each year between 2020 and 2030. This calculation combined the above state-
specific inputs with business-as-usual regional estimates of electricity retail sales.40 Based on
EPA’s estimates, the EE improvements would yield cumulative reductions in electricity
generation in the range of 9% to 12% by 2030, depending on the state’s EE starting point.
EPA applied each state’s annual (2020-2029) cumulative reductions (as a percentage of sales) to
the amount of total electricity (including hydropower) sold to in-state consumers in 2012. EPA
adjusted this value to account for states that are net importers or exporters of electricity. Some
states (e.g., Idaho and Delaware) import close to 50% of the electricity sold in their state. Other
states (e.g., North Dakota, Wyoming, and West Virginia) generate more than twice the amount of
electricity they use in-state, exporting the additional electricity to neighboring states.
For net importers, EPA adjusted the cumulative reductions by applying the cumulative reduction
percentage to in-state sales, multiplied by the in-state generation as a percentage of sales. For
example, Delaware’s in-state generation as a percentage of sales equaled 45%, meaning it
imported 55% of its total electricity in 2012. To calculate Delaware’s cumulative EE reductions,
EPA multiplied Delaware’s electricity sales (12 million MWh) by its generation as a percentage
of sales (0.45) by its cumulative EE reduction percentage (9.5% in 2029).
For net exporters, the EE cumulative reduction percentages only apply to in-state electricity sales,
not the total amount of electricity generated. The resulting avoided electricity generation values
for each state are added to the denominator in the emission rate equation (Table 5).
The impacts of applying building block 4 to the emission rate equation vary by state. In general,
the effects appear to be more pronounced in states that generate a large percentage of their
electricity from sources that are not already included in the emission rate equation. This primarily
involves hydroelectric power, and to some extent, nuclear power generation. For example,
building block 4 appears to have a greater effect in Washington (77% of total power generation
from hydropower), Idaho (71% from hydropower), and Oregon (65% from hydropower).
Building block 4 includes hydroelectric power generation as part of the total generation subject to
EE reductions, but this is the only instance in which MWh from hydroelectric power generation
are part of the emission rate equation.
In addition, the EE methodology appears to have a greater effect in states with relatively high
percentages of nuclear power generation, such as South Carolina (53% nuclear power) and New

40 EPA generated these projections by using the 2012 retail sales data and average annual growth rates for different
regions provided in EIA’s 2013 Annual Energy Outlook.
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Jersey (51% nuclear power). Although existing nuclear power is captured in the emission rate
equation, it only accounts for the at-risk (5.8%) component.
By comparison, the effects of building block 4 are less pronounced in states that export a
substantial amount of the electricity they generate, such as Wyoming, North Dakota, and West
Virginia. These states generate more than twice as much electricity as they consume. The total
generation from affected EGUs is captured in the equation’s numerator, but only the avoided
generation from in-state sales is captured in the denominator, resulting in a lesser impact from
building block 4.
What do the different effects of the EE building block mean for states? The states that generate a
considerable percentage of electricity from either hydroelectric power or nuclear power may have
more limited options to find emission rate reductions than other states. The inclusion of avoided
generation from all electricity generating sources may compel these states to focus on EE
improvements to reach their emission rate targets. This potential outcome assumes these states
cannot find rate reductions from their existing hydroelectric or nuclear power sources.
Concluding Observations
As Table 6 indicates, the building blocks affect each state’s emission rate baseline in different
ways, depending on each state’s specific electricity generation circumstances. Table 6 presents an
incremental analysis of the impacts of applying the building blocks in a stepwise fashion (or all at
once), ultimately reaching the 2030 emission rate goal.
As another measure of a state-by-state comparison, CRS used EPA’s emission rate methodology
to calculate the impacts of each building block in isolation. The results are listed in Table 7.
These calculations illustrate the relative impacts of the four building blocks for each state. For
example in Idaho, building blocks 1, 2, and 3 (nuclear) have no impact on the 2012 emission rate,
because Idaho has no coal-fired EGUs, no room to improve its NGCC utilization, and no nuclear
generation. Therefore, the only impacts to its 2012 baseline rate are due to the renewable
component of building block 3 and EE improvements from building block 4.
As Table 7 indicates, on average, building block 1 has the smallest impact (4%), decreasing state
emission rate goals (compared to 2012 baselines) by a range of 0% to 6%. The emission rates in
states (e.g., Rhode Island, Maine, and Idaho) without coal-fired, steam EGUs are unaffected by
this block; states that employ coal-fired units to generate a significant percentage of their
electricity (e.g., Kentucky, West Virginia, and Wyoming) see a greater impact to their emission
rates.
Building block 2, on average, generates the largest (tied with block 4 below) incremental impact
(13%), ranging from a 0% to 38% change (compared to baseline). The largest changes are seen in
states that have both coal-fired EGUs and under-utilized NGCC plants. The smallest impacts are
in states without any NGCC and states that already have relatively high NGCC utilization rates.
Although the nuclear component of building block 3 only affects three states, its impacts are
considerable in those states.
The RE component of building block 3, on average, reduces emission rate baselines by 9% (10%
if the negative values are omitted). The impacts from the RE block application range from 2% to
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33%. Multiple factors explain this range of impacts. For example, this block has a considerable
effect in Washington (33%), because it increases the state’s RE generation by 116% and RE
accounts for a substantial percentage of the state’s total generation (not counting hydroelectric
power): 30% in 2012 and 65% in 2030. Although Kentucky’s RE generation increases by 415%
between 2012 and 2030 (from 0.4% to 2%), the RE block has a relatively small impact, because
RE continues to account for a small percentage of the state’s total generation.
Building block 4 has the largest impact (tied with block 2) on emission rate baselines, reducing
them, on average, by 13%, but the range of impacts is between 4% and 37%. This range is a
result of several factors, including (1) the contribution of in-state electricity generation that comes
from hydroelectric power or nuclear power; and (2) whether the state is a net importer or net
exporter of electricity.
Although the isolated building block application (in Table 7) provides a comparison of the
relative magnitude of potential effects in each state, states have the flexibility to combine the
building blocks (and/or other potential activities) to meet their emission rate targets. EPA’s
building blocks were meant to establish the emission rate goals, not predict a particular outcome
in a state’s electricity generation profile.
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Table 5. Equation for CO2 Emission Rate Goals
Building Block (BB) Adjustments
coal
generation
OG generation
NGCC generation
(BB2)
(BB2)
(BB2)
“Other”
X
+ X
+ X
+
CO2






emissions
2030
coal
OG emission
NGCC emission
Emission
emission
rate
rate
Rate
= rate (BB1)
Goal
“At-risk”
and under
Renewable
Avoided
coal
OG generation
NGCC generation
“Other”
construction
energy
generation
generation
+ (BB2)
+ (BB2)
+ generation +
nuclear
+
generation
+ from energy
(BB2)
generation
(BB3)
efficiency
(BB4)
(BB3)
Source: Prepared by CRS; additional information in EPA, Goal Computation Technical Support Document, at http://www2.epa.gov/carbon-pol ution-standards/clean-power-
plan-proposed-rule-technical-documents.
Notes: OG = oil and gas; NGCC = natural gas combined cycle; “other” generation includes fossil fuel EGUs, such as integrated gasification combined cycle (IGCC) units,
high utilization combustion turbine units, and applicable thermal output at cogeneration units; “at-risk” nuclear includes 5.8% of a state’s nuclear power capacity;
renewable energy includes solar, wind, geothermal, wood and wood-derived fuels, other biomass, but not hydroelectric power.

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Table 6. 2012 State Emission Rate Baselines and Building Block Applications
Emission rate baselines in pounds of CO2 emissions per MWh
Blocks 1-4
State
2012 Emission
Percent Reduction
Rate Baseline
Block 1
Blocks 1-2 Blocks 1-3 (2030 Emissions
from 2012 Baseline
Rate Goal)
Alabama 1,444
1,385
1,264
1,139
1,059
27%
Alaska 1,351
1,340
1,237
1,191
1,003
26%
Arizona 1,453
1,394
843
814
702
52%
Arkansas 1,634
1,554
1,058
996
910
44%
California 698
697
662
615
537
23%
Colorado 1,714
1,621
1,334
1,222
1,108 35%
Connecticut 765
764
733
643
540 29%
Delaware 1,234
1,211
996
892
841 32%
Florida 1,199
1,169
882
812
740
38%
Georgia 1,500
1,433
1,216
926
834
44%
Hawai 1,540
1,512
1,512
1,485
1,306
15%
Idaho 339
339
339
291
228
33%
Illinois 1,894
1,784
1,614
1,476
1,271
33%
Indiana 1,924
1,817
1,772
1,707
1,531
20%
Iowa 1,552
1,461
1,304
1,472
1,301
16%
Kansas 1,940
1,828
1,828
1,658
1,499
23%
Kentucky 2,158
2,028
1,978
1,947
1,763
18%
Louisiana 1,455
1,404
1,043
978
883
39%
Maine 437
437
425
451
378
14%
Maryland 1,870
1,772
1,722
1,394
1,187
37%
Massachusetts 925
915
819
661
576 38%
Michigan 1,690
1,603
1,408
1,339
1,161
31%
Minnesota 1,470
1,389
999
1,042
873 41%
Mississippi 1,093
1,071
809
752
692 37%
Missouri 1,963
1,849
1,742
1,711
1,544
21%
Montana 2,246
2,114
2,114
1,936
1,771
21%
Nebraska 2,009
1,889
1,803
1,652
1,479 26%
Nevada 988
970
799
720
647
35%
New Hampshire
905
887
710
532
486
46%
New Jersey
928
916
811
616
531
43%
New Mexico
1,586
1,513
1,277
1,163
1,048
34%
New York
978
970
828
652
549
44%
North Carolina
1,647
1,560
1,248
1,125
992
40%
Congressional Research Service
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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

Blocks 1-4
State
2012 Emission
Percent Reduction
Rate Baseline
Block 1
Blocks 1-2 Blocks 1-3 (2030 Emissions
from 2012 Baseline
Rate Goal)
North Dakota
1,994
1,875
1,875
1,865
1,783
11%
Ohio 1,850
1,751
1,673
1,512
1,338
28%
Oklahoma 1,387
1,334
1,053
964
895 35%
Oregon 717
701
565
452
372
48%
Pennsylvania 1,531
1,458
1,393
1,157
1,052 31%
Rhode Island
907
907
907
867
782
14%
South Carolina
1,587
1,506
1,342
866
772
51%
South Dakota
1,135
1,067
732
900
741
35%
Tennessee 1,903
1,797
1,698
1,322
1,163 39%
Texas 1,284
1,235
979
861
791
38%
Utah 1,813
1,713
1,508
1,454
1,322
27%
Virginia 1,302
1,258
1,047
894
810
38%
Washington 756
728
444
298
215 72%
West Virginia
2,019
1,898
1,898
1,687
1,620
20%
Wisconsin 1,827
1,728
1,487
1,379
1,203 34%
Wyoming 2,115
1,988
1,957
1,771
1,714 19%
Source: Prepared by CRS; data from EPA, Goal Computation Technical Support Document, at
http://www2.epa.gov/carbon-pol ution-standards/clean-power-plan-proposed-rule-technical-documents.
Notes: EPA did not establish emission rate goals for Vermont and the District of Columbia because they do not
currently have affected EGUs.

Congressional Research Service
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Table 7. Application of EPA’s Building Blocks in Isolation
Percent
Percent
Percent
Percent
Percent
2012
Reduction
Reduction
Block 3
Reduction
Block 3
Reduction
Reduction
State
Emission
Block 1
from
Block 2
from
(Nuclear)
from
(Renewables)
from
Block 4
from
Rate Baseline
Baseline
Baseline
Baseline
Baseline
Baseline
Alabama 1,444
1,385
4%

1,311
9%
1,444
0%
1,301
10%
1,332
8%
Alaska
1,351
1,340 1%

1,237 8%
1,351 0% 1,301 4%
1,131 16%
Arizona
1,453
1,394 4%

843 42%
1,453 0% 1,404 3%
1,247 14%
Arkansas
1,634
1,554 5%

1,087 34%
1,634 0% 1,538 6%
1,485
9%
California
698
697 0%

662 5% 698 0%
645 7% 598 14%
Colorado
1,714
1,621 5%

1,394 19%
1,714 0% 1,567 9%
1,538 10%
Connecticut 765
764
0%

733
4%
765
0%
671
12%
629
18%
Delaware 1,234
1,211
2%

999
19%
1,234
0%
1,105
10%
1,156
6%
Florida
1,199
1,169 3%

885 26%
1,199 0% 1,101 8%
1,083 10%
Georgia
1,500
1,433 5%

1,261 16%
1,243 17% 1,355 10% 1,310
13%
Hawai
1,540
1,512 2%

1,540 0%
1,540 0% 1,512 2%
1,350 12%
Idaho 339
339
0%

339
0%
339
0%
291
14%
257
24%
Illinois
1,894
1,784 6%

1,705 10%
1,894 0% 1,732 9%
1,609 15%
Indiana
1,924
1,817 6%

1,874 3%
1,924 0% 1,853 4%
1,719 11%
Iowa 1,552
1,461
6%

1,377
11%
1,552
0%
1,752
-13%
1,390
10%
Kansas
1,940
1,828 6%

1,940 0%
1,940 0% 1,759 9%
1,738 10%
Kentucky
2,158
2,028 6%

2,093 3%
2,158 0% 2,123 2%
1,944 10%
Louisiana
1,455
1,404 3%

1,067 27%
1,455 0% 1,364 6%
1,305 10%
Maine 437
437
0%

424
3%
437
0%
465
-6%
370
16%
Maryland 1,870
1,772
5%

1,815
3%
1,870
0%
1,513
19%
1,538
18%
Massachusetts 925
915
1%

819
11%
925
0% 747
19%
781 16%
CRS-23

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Percent
Percent
Percent
Percent
Percent
2012
Reduction
Reduction
Block 3
Reduction
Block 3
Reduction
Reduction
State
Emission
Block 1
Block 2
Block 4
Rate Baseline
from
from
(Nuclear)
from
(Renewables)
from
from
Baseline
Baseline
Baseline
Baseline
Baseline
Michigan
1,690
1,603 5%

1,476 13%
1,690 0% 1,607 5%
1,456 14%
Minnesota 1,470
1,389
5%

1,038
29%
1,470
0%
1,533
-4%
1,239
16%
Mississippi
1,093
1,071 2%

809 28%
1,130 0% 1,040 8%
1,020 10%
Missouri
1,963
1,849 6%

1,844 6%
1,963 0% 1,928 2%
1,769 10%
Montana
2,246
2,114 6%

2,246 0%
2,246 0% 2,058 8%
2,038
9%
Nebraska
2,009
1,889 6%

1,910 5%
2,009 0% 1,840 8%
1,781 11%
Nevada 988
970
2%

799
19%
988
0%
890
10%
878
11%
New
Hampshire
905 887
2%
710
22% 905
0%
678 25%
804
11%
New Jersey
928
916
1%
811
13%
928
0%
704
24%
766
17%
New Mexico
1,586
1,513
5%
1,326
16%
1,586
0%
1,444
9%
1,415
11%
New York
978
970
1%
828
15%
978
0%
771
21%
790
19%
North
Carolina
1,647 1,560
5%
1,298
21% 1,647
0%
1,463
11%
1,407
15%
North Dakota
1,994
1,875
6%
1,994
0%
1,994
0%
1,984
1%
1,907
4%
Ohio 1,850
1,751
5%

1,763
5%
1,850
0%
1,669
10%
1,613
13%
Oklahoma
1,387
1,334 4%

1,079 22%
1,387 0% 1,269 8%
1,280
8%
Oregon 717
701
2%

565
21%
717
0%
573
20%
565
21%
Pennsylvania 1,531
1,458
5%

1,458
5%
1,531
0%
1,272
17%
1,367 11%
Rhode Island
907
907
0%
907
0%
907
0%
867
4%
814
10%
South
Carolina
1,587
1,506 5%

1,406 11%
1,147 28% 1,361 14% 1,335
16%
South Dakota
1,135
1,067
6%
754
34%
1,135
0%
1,395
-23%
965
15%
Tennessee 1,903
1,797
6%

1,794
6%
1,581
17%
1,762
7%
1,618
15%
CRS-24

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Percent
Percent
Percent
Percent
Percent
2012
Reduction
Reduction
Block 3
Reduction
Block 3
Reduction
Reduction
State
Emission
Block 1
Block 2
Block 4
Rate Baseline
from
from
(Nuclear)
from
(Renewables)
from
from
Baseline
Baseline
Baseline
Baseline
Baseline
Texas 1,284
1,235
4%

1,002
22%
1,284
0%
1,129
12%
1,167
9%
Utah
1,813
1,713 6%

1,584 13%
1,813 0% 1,748 4%
1,643
9%
Virginia 1,302
1,258
3%

1,067
18%
1,302
0%
1,076
17%
1,133
13%
Washington 756
728
4%

444
41%
756
0%
506
33%
479
37%
West Virginia
2,019
1,898
6%
2,019
0%
2,019
0%
1,794
11%
1,929
4%
Wisconsin
1,827
1,728 5%

1,561 15%
1,827 0% 1,694 7%
1,577 14%
Wyoming 2,115
1,988
6%

2,075
2%
2,115
0%
1,911
10%
2,039
4%












Average
4% 13% 1%
9%
13%
Source: Prepared by CRS; data from EPA, technical support document spreadsheets, at http://www2.epa.gov/carbon-pol ution-standards/clean-power-plan-proposed-
rule-technical-documents.
Notes: Using EPA’s emission rate formula and underlying data (provided in EPA spreadsheets), CRS calculated the impacts that each building block would have on the
emission rate baselines. The building block applications examine their impacts in isolation. For example, the data in the block 2 column do not include the impacts of
applying block one methodology, only the effects of applying block 2.
EPA did not establish emission rate goals for Vermont and the District of Columbia because they do not currently have affected EGUs.
CRS-25

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State CO2 Emission Rate Goals in EPA’s Proposed Rule for Existing Power Plants

Author Contact Information
Jonathan L. Ramseur
Specialist in Environmental Policy
jramseur@crs.loc.gov, 7-7919

Congressional Research Service
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