1

King, Melanie

From: King, Melanie

Sent: Friday, October 17, 2014 2:26 PM

To: Higgins, Cortney

Cc: Elman, Barry; Wayland, Robertj; Schreifels, Jeremy

Subject: EO 12866 review of RIN 2060-AR33 Carbon Pollution Guidelines for EGUs in Indian Country 

and Territories - draft TSD

Attachments: TribeTerritoryGoals.xlsx; TSD.DOCX

Hi Cortney,

The draft TSD for the supplemental proposal is attached.  We're still working to provide a little more detail on

how the goals change with the application of each building block (similar to Appendix 5 in the June proposal's

Goal Computation TSD) and should have an updated version early next week.

Melanie King 

Energy Strategies Group 

Sector Policies and Programs Division 

Office of Air Quality Planning and Standards 

U.S. Environmental Protection Agency 

Mail Code D243-01 

RTP, NC 27711 

Phone: (919) 541-2469 

Fax: (919) 541-5450 

king.melanie@epa.gov
Technical Support Document for 

Calculating Carbon Pollution Goals for Existing 

Power Plants in Territories and Areas of Indian 

Country 

October 1, 2014
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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CONTENTS 

Acronyms and initialisms............................................................................................................................... i

Introduction ..................................................................................................................................................1

Affected electricity generating units on tribal lands .................................................................................... 1

Overview ...................................................................................................................................................1

Data...........................................................................................................................................................2

BSER factors informing tribal lands’ emission rate goals.......................................................................... 3

Building block 1 – heat rate improvement at coal‐fired power plants................................................. 3

Building block 2 – redispatch to lower‐emitting NGCC EGUs............................................................... 3

Building block 3 – renewables .............................................................................................................. 3

Building block 4 – energy efficiency...................................................................................................... 4

Affected electricity generating units in U.S. territories................................................................................ 4

Overview ...................................................................................................................................................4

Data...........................................................................................................................................................7

BSER factors informing territories’ emission rate goals ......................................................................... 10

Building block 1 – heat rate improvement at coal‐fired power plants............................................... 10

Building block 2 – redispatch to lower‐emitting NGCC EGUs............................................................. 11

Building block 3 – renewables ............................................................................................................ 11

Building block 4 – energy efficiency.................................................................................................... 11

ACRONYMS AND INITIALISMS 

BSER best system of emission reduction

CC combined cycle

CO2 carbon dioxide

CT combustion turbine

EGU electric generating unit

GHG greenhouse gas

GPA Guam Power Authority

ICE internal combustion engine

LNG liquified natural gas

NGCC natural gas combined cycle

PREPA Puerto Rico Electric Power Authority

ST steam turbine

VIWAPA U.S. Virgin Islands Water and Power Authority
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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INTRODUCTION 

In the June 2014 Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric Utility

Generating Units (hereafter referred to as “June 2014 proposed rule”), EPA proposed to establish carbon

dioxide (CO2) emission guidelinesfor existing electricity generating units(EGUs) in the 50 states of the U.S.

The Agency also indicated that it would propose a supplemental rule that included CO2 guidelines for

existing EGUs in the territories and areas of Indian country (hereafter referred to as “tribal lands”).  

Based on the June 2014 proposed rule, the Agency identified the best system of emission reduction (BSER)

that, taking into account the cost of achieving emission reductions and non‐air quality health and

environmental impact and energy requirements, the Administrator determines has been adequately

demonstrated. Based on its evaluation of adequately‐demonstrated greenhouse gas (GHG) abatement

measures, the Agency listed four categories, or “building blocks,” that are technically viable and broadly

applicable, and can provide cost‐effective reductionsin CO2 emissionsfrom existing EGUs. These “building

blocks” include:

1. Reducing the CO2 intensity of generation at individual affected EGUs through heat rate

improvements;

2. Reducing emissions from the most CO2‐intensive affected EGUs in the amount that results from

substituting generation at those EGUs with generation from less CO2‐intenstive affected EGUs

(e.g., natural gas combined cycle (NGCC) EGUs);

3. Reducing emissions from affected EGUs in the amount that results from substituting generation

at those EGUs with expanded generation at low‐ or zero‐CO2 EGUs; and,

4. Reducing emissions from affected EGUs in the amount that results from the use of demand‐side

energy efficiency that reduces the amount of generation required.

The Agency believes that for purposes of Clean Air Act section 111(d), as applied to the power sector, the

BSER encompasses all four “building blocks.”

This Technical Support Document (TSD) describes how the Agency applied the BSER from the June 2014

proposal to affected EGUs on tribal lands and in territories.  

AFFECTED ELECTRICITY GENERATING UNITS ON TRIBAL LANDS 

Overview 

There are four power plants with 12 affected EGUs on tribal lands (see Table 1). Three plants combust

coal and one plant has two NGCC EGUs. The EGUs on tribal lands operate as part of an integrated

electricity grid and supply the majority of their electricity generation to customers outside the tribal lands.  

The Agency did not find any information about grid‐connected renewable energy existing in 2012 on tribal

lands with affected EGUs and, therefore, assumed no existing renewable energy sources.

Table 1: Potentially affected EGUs on tribal lands

Tribe ORIS Plant name Unit   Fuel Unit type Capacity

(MW)

Navajo 2442 Four Corners 1 coal steam turbine 190

Navajo 2442 Four Corners 2 coal steam turbine 190

Navajo 2442 Four Corners 3 coal steam turbine 253
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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Navajo 2442 Four Corners 4 coal steam turbine 818

Navajo 2442 Four Corners 5 coal steam turbine 818

Navajo 4941 Navajo Generating Station NAV1 coal steam turbine 803

Navajo 4941 Navajo Generating Station NAV2 coal steam turbine 803

Navajo 4941 Navajo Generating Station NAV3 coal steam turbine 803

Ute 7790 Bonanza 1 coal steam turbine 500

Fort Mojave 55177 South Point Energy Center A gas NGCC 236

Fort Mojave 55177 South Point Energy Center B gas NGCC 236

Fort Mojave 55177 South Point Energy Center ST1 gas NGCC 236

Data 

The 2012 CO2 emissions and electricity generation data for the EGUs listed in Table 1 are taken from the

document titled, 2012 Unit‐level Data Using the eGRID Methodology.

1 Information about the source of

these data and the methodologies used to compile the data set is described in Description of 2012 Unit‐

Level Data Using the eGRID Methodology.

2

  

The information available to the Agency indicates there was no generation from utility‐scale, grid‐

connected renewable energy in 2012 in the three tribal lands with affected EGUs. This was based on a

review of information from EIA, DOE’s Office of Indian Energy, and tribal utility authorities serving tribal

lands with affected EGUs.

Data required for the calculation of building block 4 goals for tribal lands and their sources are:

1. 2012 electricity sales (MWh): Form EIA‐8613

  

2. 2012 energy efficiency incremental effects – total (MWh): Form EIA‐8614

  

3. Projected annual electricity sales by region (2012‐2040): AEO2013 Reference Case5

  

These data are inputs to the supporting technical files to this TSD [reference EE spreadsheet files].

Table 2 summarizes data on 2012 electricity sales for tribal lands by state and utility. None of the tribes

reported energy efficiency data on their Form EIA‐861 submittals for 2012.  Projected annual electricity

sales by region are included in the supporting technical files to this TSD.

Table 2: 2012 total electricity sales for tribal lands

Tribe Utility number Utility name State Total sales

(MWh)

Ute 12866 Moon Lake Electric Assn Inc UT 470,007

Navajo 13314 Navajo Tribal Utility Authority AZ 548,934

Navajo 13314 Navajo Tribal Utility Authority NM 117,010

Navajo 13314 Navajo Tribal Utility Authority UT 10,070

Fort Mojave 58123 Aha Macav Power Service AZ 47,788

                                                            

1 Available in the docket EPA‐HQ‐OAR‐2013‐0602 at http://www.regulations.gov/#!documentDetail;D=EPA‐HQ‐

OAR‐2013‐0602‐0254. 2 2 Available in the docket EPA‐HQ‐OAR‐2013‐0602 at http://www.regulations.gov/#!documentDetail;D=EPA‐HQ‐

OAR‐2013‐0602‐0257. 3 Available at http://www.eia.gov/electricity/data/eia861/ (see “retail sales” workbook). 4 Available at http://www.eia.gov/electricity/data/eia861/ (see “dsm” workbook). 5 Available at http://www.eia.gov/forecasts/archive/aeo13/.  
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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BSER factors informing tribal lands’ emission rate goals 

The methodology for calculating tribal lands’ emission rate goals generally applies the same approach to

determining BSER as described in the Goal Computation TSD from the June 2014 proposed rule.

Information about the BSER measures can be found in the GHG Abatement Measures TSD.6 The GHG

Abatement Measures TSD describes the categories of emission reduction measures (building blocks) used

in determining the emission rate goals.  

Building block 1 – heat rate improvement at coal‐fired power plants

Using the data discussed above, the Agency applied a 6% heat rate improvement to the EGUs at the Four

Corners, Navajo Generating Station, and Bonanza coal‐fired power plants. To calculate the alternative goal,

the Agency applied a 4% heat rate improvement to the EGUs. The results from building block 1 are

presented in Table 3.

Table 3: Adjusted average coal CO2 emission rate for coal‐fired EGUs

Tribe 6% HRI

Coal CO2 rate

(lbs/MWh)

4% HRI

Coal CO2 rate

(lbs/MWh)

Navajo 1,993 2,036

Ute 2,016 2,059

Building block 2 – redispatch to lower‐emitting NGCC EGUs

Because none of the tribal lands have both coal‐fired EGUs and NGCC EGUs, the analysis does not include

redispatch to less CO2‐intenstive affected EGUs.

Building block 3 – renewables

The analysis of renewable energy for building block 3 used the proposed methodology from the June 2014

proposed rule. Because EPA did not find any information about utility‐scale, grid‐connected renewable

energy net generation on tribal lands with affected EGUs in 2012, the renewables targets are zero, and,

therefore, result in no change to the goals for these areas.

EPA did not propose renewable energy targets for goal calculations based on the co‐proposed

methodology for the U.S. territories or the alternative approach used in the June 2014 proposed rule as

discussed in the preamble. However, EPA considered using the renewable energy technical potential

estimates for tribal lands7,8 as well as using the lowest renewable energy percentage target (as derived in

the alternative approach upon which EPA solicited comment for states) of any state in which that area of

Indian country is located. Because these co‐proposed methodology and alternative approach are based

on a state or territory’s total net electricity generation and not retail sales (i.e., consumption), applying

                                                            

6 Available in the docket EPA‐HQ‐OAR‐2013‐0602 at http://www.regulations.gov/#!documentDetail;D=EPA‐HQ‐

OAR‐2013‐0602‐0437. 7 Doris et al (DOE), 2013. Geospatial Analysis of Renewable Energy Technical Potential on Tribal Lands. Available at

http://www.nrel.gov/docs/fy13osti/56641.pdf.    8 Lopez et al (NREL), 2012. U.S. Renewable Energy Technical Potentials: A GIS‐Based Analysis. Available at

http://www.nrel.gov/docs/fy12osti/51946.pdf.  
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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these methodologiesto tribal lands – where sales are only 2% ‐ 16% of generation –  yieldslarge renewable

energy goals relative to retail sales.

Building block 4 – energy efficiency

The analysis of energy efficiency for building block 4 used the proposed methodology from the June 2014

proposed rule.

AFFECTED ELECTRICITY GENERATING UNITS IN U.S. TERRITORIES 

Overview 

The territories or Guam, Puerto Rico, and the US Virgin Islands have coal‐, oil‐, and/or gas‐fired EGUs that

may be affected by this proposal. Data from these EGUs were analyzed to establish territorial goals using

the BSER described above.  

The Guam Power Authority (GPA) owns and manages the territory’s electricity grid. The majority of

electricity on Guam is generated from No. 6 heavy fuel oil with a small amount from No. 2 distillate oil,

both of which are shipped to the territory by tanker. 9 There are nine fossil‐fired EGUs in Guam greater

than 25 MW nameplate capacity (see Table 4). Excluding Guam’s internal combustion engines (ICEs) and

oil‐fired combustion turbines(CTs),10 there are four EGU heavy fuel oil‐fired steam turbine (STs) EGUsthat

may be affected sources under the rule.  

Guam is also pursuing renewable energy and energy efficiency. In 2008, Guam’s legislature established a

renewable energy goal of 8% of net electricity sales by December 31, 2020; 10% of net electricity sales by

December 31, 2025; and 15% of net electricity sales by December 31, 2030.11

Table 4: Guam fossil‐fired EGUs greater than 25 MW capacity

Plant name (location) Unit   Fuel Unit type Capacity

(MW)

Cabras 1 No. 6 oil ST 60 *

Cabras 2 No. 6 oil ST 60 *

Cabras   3 No. 6 oil ICE 38

Cabras 4 No. 6 oil ICE 38   

Tanguisson 1 No. 6 oil ST 25 *

Tanguisson 2 No. 6 oil ST 25 *

PITI 7 distillate oil CT 40

PITI 8 No. 6 oil ICE 40   

PITI 9 No. 6 oil ICE 40

Note: EGUs with asterisks were included in the goal calculation for Guam

                                                            

9 EIA, 2013. Guam – Territory Energy Profile Analysis. Available at http://www.eia.gov/state/analysis.cfm?sid=gq.   10 The June 2014 proposed rule does not include ICEs as affected sources, and CTs must combust natural gas for

more than 90% of the CT’s heat input. Since available data indicate Guam’s CT did not combust natural gas, it has

been excluded from the list of potentially affected units for purposes of this goal‐setting analysis. 11 NCSU, 2014. Guam – Renewable Energy Portfolio Goal. Available at

http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=GU03R&ee=1
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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The Puerto Rico Electric Power Authority (PREPA) owns and manages the territory’s electricity grid. In

2012, approximately 65% of the electricity was generated from No. 6 heavy fuel oil and No. 2 distillate oil,

18% from liquified natural gas (LNG), 16% from coal, and 1% from hydro.12 There are several fossil‐fired

EGUs in Puerto Rico greater than 25 MW nameplate capacity (see Table 5). Excluding oil‐fired CTs and

combined cycles (CCs),13 there are 2 coal‐fired ST EGUs, 2 NGCC EGUs, and 14 oil‐fired ST EGUs that may

be affected sources under the rule.  

Puerto Rico is also pursuing renewable energy and energy efficiency. In 2010, Puerto Rico enacted a

renewable energy portfolio standard of 15% of retail electricity sales in 2020, rising to 20% in 2035.14

Table 5: Puerto Rico fossil‐fired EGUs greater than 25 MW capacity

Plant name (location) Unit   Fuel Unit type Capacity

(MW)

AES (Guayama) 1 coal ST 227 *

AES (Guayama) 2 coal ST 227 *

Eco‐electrica (Penuelas) CT1 gas NGCC 568 *

Eco‐electrica (Penuelas) CT2 gas NGCC 568 *

PREPA Aguirre (Aguirre) AG1 No. 6 oil   ST 450 *

PREPA Aguirre (Aguirre) AG2 No. 6 oil ST 450 *

PREPA Aguirre (Aguirre) CC1 distillate oil CC 296

PREPA Aguirre (Aguirre) CC2 distillate oil CC 296   

PREPA Aguirre (Aguirre) T1‐1 distillate oil CT 30

PREPA Aguirre (Aguirre) T1‐2 distillate oil CT 30   

PREPA Cambalache (Arecibo) C1 distillate oil CT 83

PREPA Cambalache (Arecibo) C2 distillate oil CT 83   

PREPA Cambalache (Arecibo) C3 distillate oil CT 83

PREPA Daguao (Ceiba) T1‐1 distillate oil CT 30   

PREPA Daguao (Ceiba) T1‐2 distillate oil CT 30

PREPA Jobos (Guayama) T1‐1 distillate oil CT 227   

PREPA Jobos (Guayama) T1‐2 distillate oil CT 227

PREPA Mayaquez GT5 distillate oil CT 28   

PREPA Mayaquez GT6 distillate oil CT 28

PREPA Mayaquez GT7 distillate oil CT 28   

PREPA Mayaquez GT8 distillate oil CT 28

PREPA Palo Seco (Toa Baja) PS1 No. 6 oil   ST 85 *

PREPA Palo Seco (Toa Baja) PS2 No. 6 oil ST 85 *

PREPA Palo Seco (Toa Baja) PS3 No. 6 oil   ST 216 *

PREPA Palo Seco (Toa Baja) PS4 No. 6 oil ST 216 *

PREPA Palo Seco (Toa Baja) GT1‐1 distillate oil CT 30   

                                                            

12 EIA, 2014. Puerto Rico Territory Energy Profile. Available at http://www.eia.gov/state/print.cfm?sid=RQ 13 In the June 2014 proposed rule, affected CTs are defined as those that combust natural gas for more than 90% of

the CT’s heat input. Since available data indicate Puerto Rico’s CTs did not combust natural gas, those units have

been excluded from the list of potentially affected units. 14 NCSU, 2014. Puerto Rico – Renewable Energy Portfolio Standard. Available at

http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=PR07R&ee=1
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PREPA Palo Seco (Toa Baja) GT1‐2 distillate oil CT 30

PREPA Palo Seco (Toa Baja) GT2‐1 distillate oil CT 30   

PREPA Palo Seco (Toa Baja) GT2‐2 distillate oil CT 30

PREPA Palo Seco (Toa Baja) GT3‐1 distillate oil CT 30   

PREPA Palo Seco (Toa Baja) GT3‐2 distillate oil CT 30

PREPA San Juan (San Juan) SJ7 No. 6 oil   ST 100 *

PREPA San Juan (San Juan) SJ8 No. 6 oil ST 100 *

PREPA San Juan (San Juan) SJ9 No. 6 oil   ST 100 *

PREPA San Juan (San Juan) SJ10 No. 6 oil ST 100 *

PREPA San Juan (San Juan) CC5 distillate oil CC 232   

PREPA San Juan (San Juan) CC6 distillate oil CC 232

PREPA South Coast (Guiyanilla) SC3 No. 6 oil   ST 85 *

PREPA South Coast (Guiyanilla) SC4 No. 6 oil ST 85 *

PREPA South Coast (Guiyanilla) SC5 No. 6 oil   ST 410 *

PREPA South Coast (Guiyanilla) SC6 No. 6 oil ST 410 *

PREPA South Coast (Guiyanilla) GT1 distillate oil CT 45   

PREPA South Coast (Guiyanilla) GT2 distillate oil CT 45

PREPA Vega Baja GT1‐1 distillate oil CT 30   

PREPA Vega Baja GT1‐2 distillate oil CT 30

PREPA Yabucoa (Humacao) GT1‐1 distillate oil CT 30   

PREPA Yabucoa (Humacao) GT1‐2 distillate oil CT 30

Note: EGUs with asterisks were included in the goal calculation for Puerto Rico

The U.S. Virgin Islands Water and Power Authority (VIWAPA), an independent government agency,

manages the territory’s two separate electricity grids. There are several fossil‐fired EGUs in the U.S. Virgin

Islands, but most are less than 25 MW nameplate capacity. The Agency found information about 3 fossil‐

fired EGUs greater than 25 MW (see Table 6). Excluding the oil‐fired combustion turbine (CT) EGU,15 there

is 1 coal‐fired ST EGU that has not operated in more than 20 years and 1 oil‐fired ST EGU that has not

operated since 2011. Because there are not 2012 data for the analysis and because there is no indication

that VIWAPA will return these units to operation, the analysis does not include a goal calculation for the

U.S. Virgin Islands.

Table 6: Virgin Island fossil‐fired EGUs greater than 25 MW capacity

Plant name (location) Unit   Fuel Unit type Capacity

(MW)

Krum Bay 13 No. 6 oil ST 35

Krum Bay 23 Distillate oil CT 39   

St. Croix Renaissance 10 Coal ST 25

                                                            

15 In the June 2014 proposed rule, affected CTs are defined as those that combust natural gas for more than 90% of

the CT’s heat input. Since available data indicate the U.S. Virgin Island’s CT did not combust natural gas, that unit has

been excluded from the list of potentially affected units.
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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Data 

Potentially‐affected EGUs in the U.S. territories do not report comprehensive information to the Agency

or the Energy Information Administration (EIA). Therefore, the Agency compiled data from a variety of

sources, including:

 EPA’s Greenhouse Gas Reporting Program16  

 Puerto Rico Electric Power Authority (PREPA)

 U.S. Virgin Islands Power and Water Authority (VIWAPA)

 Guam Power Authority (GPA)

 EIA’s form EIA‐861

The territory goals are described as a CO2 emission rate (lb of CO2 per MWh of net electricity generation).

However, the Agency did not have comprehensive unit‐level data available on both CO2 emissions and net

electricity generation. For Guam, the Agency received unit‐level net generation and fuel consumption

data from GPA. For Puerto Rico, the Agency had unit‐level CO2 emission data reported by the power

companies to the EPA’s Greenhouse Gas Reporting Program. Therefore, two different methodologies

were used to calculate CO2 emissions (Guam) and net electricity generation (Puerto Rico).

For Guam, GPA provided information about unit‐level net generation and fuel consumption. The Agency

used the information to calculate unit‐level CO2 emissions using the following formula:

ܥܱ2ଶ଴ଵଶ ൌ ܱܮܫଶ଴ଵଶ 	ൈ ܨܧ	

Where:

CO22012 is the 2012 annual CO2 emissions in metric tons;

OIL2012 is the 2012 annual oil consumption in gallons; and

EF is an emission factor of 0.01127 metric tons of CO2/gallon of No. 6 oil.17

For Puerto Rico, CO2 emission data for 2012 were available at the unit level, but information was not

available for unit‐level net electricity generation in 2012. The Agency estimated 2012 net electricity

generation by multiplying each unit’s ratio of maximum net electricity generation to maximum CO2

emissions by the unit’s reported CO2 emissions in 2012. The calculation is:

ܯܹ݄ଶ଴ଵଶ ൌ ൬

௫௠௔ܹ݄ܯ

௫௠௔ܱ2ܥ

൰ ൈ ܥܱ2ଶ଴ଵଶ

Where:

MWh2012 is the annual net electricity output produced by the EGU in MWh;

                                                            

16 Information about EPA’s Greenhouse Gas Reporting Program is available on the program’s website at

http://ghgdata.epa.gov/ghgp. 17 Emission factors from 40CFR Part 98 Subpart C, Table C‐1. Available at http://www.ecfr.gov/cgi‐bin/text‐

idx?SID=0769576af3d3e7d0e7c4556a2611dc4c&node=ap40.21.98_138.1&rgn=div9.  
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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MWhmax is the maximum potential annual net electricity output produced by the EGU in MWh –

calculated as nameplate capacity in MW X 8,784 hours18 X a gross‐to‐net conversion factor (see

Table 7);

CO22012 is the 2012 annual CO2 emissions in metric tons reported to the EPA’s Greenhouse Gas

Reporting Program; and

CO2max is the maximum potential CO2 emissions in metric tons – calculated as:

ܥܱ2௔௠௫ 	ൌ	

൫ܨ		 ௖ൈ 	ܷ௙ 	ൈ ܯܹ஼ைଶ 	ൈ 	ܫܪ௔௠௫		൯

2205

Where:

Fc is a carbon‐based F‐factor in standard cubic feet (scf) CO2/mmBtu (see Table 8);

Uf is a conversion factor equal to 1/385 scf CO2/lb‐mole at 14.7 psia and 68° F;

MWCO2 is the molecular weight of CO2, 44 lb/lb‐mol; and

HImax is the maximum potential annual heat input in mmBtu – calculated as:

ܫܪ௔௠௫ 	ൌ ܥ 	ൈ	

1

௠௣ߟ

	ൈ 8,784݄	 ൈ 	ܭ

Where:

C is the nameplate capacity of the unit in MW;

ηpm is the electricity generating efficiency of the prime mover‐fuel combination in

percent19 – calculated as 3.412 mmBtu/MWh20 ÷ heat rate in mmBtu/MWh for

the prime mover‐fuel combination (see Table 9)21; and

K is a constant equal to 3.412 mmBtu/MWh, the energy value of 1 MWh.

Table 7: Gross‐to‐net electricity generation factor (2012)

EGU type Net:gross

ratio

Coal ST .9360

Oil ST .9352

Natural gas CC .9728

Source: EIA, Frequently Asked Questions: What is the efficiency of different types of power plants? Available at  

Table 8: Carbon‐based F‐factors (scf/mmBtu)

                                                            

18 The number of possible operating hours in 2012.   19 For information about calculating power plant efficiency, see EIA, Frequently Asked Questions: What is the

efficiency of different types of power plants? Available at http://www.eia.gov/tools/faqs/faq.cfm?id=107&t=3. 20 One MWh of electricity is equal to 3.412 mmBtu of energy.   21 Heat rates are based on 2012 data from EIA, Electric Power Annual, Table 8.2: Average tested heat rates by prime

mover and energy source 2007‐2012. Available at http://www.eia.gov/electricity/annual/html/epa_08_02.html.  
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

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Fuel type Fc

Coal (bituminous) 1800

Oil 1420

Natural gas 1040

Source: 40CFR Part 75 App. G §2.3

Table 9: Electric generating efficiency by prime mover type and fuel (2012)

EGU type Heat rate

(mmBtu/MWh)

Coal ST 10.107

Oil ST 10.359

Natural gas 7.615

Source: EIA, Electric Power Annual, Table 8.2: Average tested heat rates by prime mover and energy source 2007‐

2012. Available at http://www.eia.gov/electricity/annual/html/epa_08_02.html.

The unit‐level data for Guam and Puerto Rico are in the supporting technical files to this TSD [reference

to goal setting worksheet files].

For renewable energy, the available information indicate that generation from utility‐scale, grid‐

connected renewable energy on Guam and Puerto Rico in 2012 was limited to hydroelectric energy on

Puerto Rico (see Table 10). The total estimated annual technical potential (MWh) for solar PV and wind

on Puerto Rico were developed using datasets for 40 km solar22 and 70m wind23 and methodologies

generally consistent with the NREL report, “U.S. Renewable Energy Technical Potentials: A GIS‐Based

Analysis.” 24 More specific information related to the methodologies for developing the datasets are

available for 40 km solar25 and 70m wind.26 Other data sources include:

1. Net generation by utility: Form EIA‐86127  

2. Existing generation: EIA territorial profiles28   

Table 10: Renewable energy net generation (MWh)

Territory Renewables 2011

(MWh)

2012  

(MWh)

Guam Hydro 0 0

Non‐hydro 0 NA

                                                            

22 National Renewable Energy Lab (NREL), 2003. Caribbean 40km Tilt Equals Latitude. Available at

www.nrel.gov/gis/data/GIS_Data_Technology_Specific/International/Solar/Low_Resolution/Caribbean_40km_Tilt

_Equals_Latitude.zip.   23 National Renewable Energy Lab (NREL), 2009. Annual average modeled wind speed (m/s) for Puerto Rico and the

Virgin Islands at a 70 meter hub height. Available at http://en.openei.org/datasets/dataset/annual‐average‐

modeled‐wind‐speed‐m‐s‐for‐puerto‐rico‐and‐the‐virgin‐islands‐at‐a‐70‐meter‐hub‐hei.   24 Lopez, et al, 2012. U.S. Renewable Energy Technical Potentials: A GIS‐Based Analysis. Available at

http://www.nrel.gov/docs/fy12osti/51946.pdf.   25 Campbell‐Howe & Wilkins‐Crowder (eds), 1999. Proceedings of the Solar 99 Conference. Available at

http://www.nrel.gov/gis/pdfs/proceedings_solar99.pdf.   26 Elliot & Schwartz, 2005. Development and Validation of High‐Resolution State Wind Resource Maps for the United

States. Available at http://www.nrel.gov/docs/fy05osti/38127.pdf.   27 Available at http://www.eia.gov/electricity/data/eia861/ (see "operational data" workbook) 28 Available at xxxxxxxxxx
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Puerto Rico Hydro 149,000 148,000

Non‐hydro 0 NA

Source: EIA, International Energy Statistics, Total Renewable Electricity Net Generation.

Data required for the calculation of building block 4 goals for territories and their sources are:

1. 2012 electricity sales (MWh): Form EIA‐86129

2. 2012 energy efficiency incremental effects – total (MWh): Form EIA‐86130

These data are inputs to the supporting technical files to this TSD [reference EE spreadsheet files].

Table 11 summarizes data on 2012 electricity sales for the territories. None of the territories reported

energy efficiency data on their Form EIA‐861 submittals for 2012. Unlike the tribes and states, electricity

sales projections are not available from the 2013 AEO reference case. EPA is not aware of another source

for this information and, thus, is holding sales constant at their 2012 levels through the analysis period.

Table 11: 2012 total electricity sales for territories

Territory Utility Number Utility Name Total Sales

(MWh)

Guam 40428 Guam Power Authority 1,563,475

Puerto Rico 15497 Puerto Rico Electric Power Authority 18,150,330

BSER factors informing territories’ emission rate goals 

As discussed in the section on BSER factors informing tribal lands’ emission rate goals, the methodology

for calculating emission rate goals generally applies the same approach to determining BSER as described

in the Goal Computation TSD from the June 2014 proposed rule.  

Building block 1 – heat rate improvement at coal‐fired power plants

Using the data discussed above, the Agency applied a 6% heat rate improvement to the coal‐fired EGUs

in Puerto Rico. The Agency assumes that a 6% heat rate improvement at the facility with the coal‐fired

EGUs will directly translate to a 6% reduction in the net CO2 emission rate. To calculate the alternative

goal, the Agency applied a 4% heat rate improvement to the EGUs. The results from building block 1 are

presented in Table 12.

Table 12: Adjusted average coal CO2 emission rate for coal‐fired EGUs

Territory 6% HRI

Coal CO2 rate

(lbs/MWh)

4% HRI

Coal CO2 rate

(lbs/MWh)

Puerto Rico 2,241 2,289

                                                            

29 Available at http://www.eia.gov/electricity/data/eia861/ (see “retail sales”). 30 Available at http://www.eia.gov/electricity/data/eia861/ (see “dsm”).
TSD for Calculating Carbon Pollution Goals for Existing Power Plants in Territories and Areas of Indian Country

11

Building block 2 – redispatch to lower‐emitting NGCC EGUs

In 2012, Puerto Rico had a one facility with two NGCC EGUs. Based on the Agency’s calculations described

above, the facility operated at approximately a 37% capacity factor. The GHG Abatement Measures TSD31,

suggeststhat the average availability of an NGCC issignificantly greaterthan 70%. Because the NGCC EGUs

in Puerto Rico use imported LNG, the Agency reviewed the capacity of the existing LNG port and gasifiers

to ensure they would not constrain the ability of the EGUs to achieve a 70% capacity factor. Based on data

available to the Agency, we believe the port has sufficient importing and processing capacity to supply

LNG for the NGCCs to achieve a 70% capacity factor which offsets generation at both coal‐fired ST EGUs

and oil‐fired ST EGUs.

Building block 3 – renewables

Because neither Guam nor Puerto Rico have utility‐scale, grid‐connected, non‐hydroelectric renewable

energy generation for 2012, the analysis of renewable energy using the proposed methodology from the

June 2014 proposed rule resulted in no renewable energy targets, and, therefore, no change to the goals

for these areas.  

The second co‐proposal option includes an adjustment to the proposed methodology that changes the

amount of renewable energy in 2017 to be consistent with the lowest amount among the 50 states in

2012, which is 0.37% of the 2012 total electricity generation. EPA then applies the 9% annual growth

factor through 2029. The 9% annual growth factor is based on Hawaii’s historical growth between 2002

and 2012 renewable energy generation.  

For Puerto Rico’s renewable energy target based on the alternative approach, the Agency used estimates

provided by DOE for wind and utility‐scale solar PV (urban and rural) from available wind and solar

resource data for the region. The wind resource data used are 70 hub height wind speed estimates

modeled by AWS Truepower and NREL in 2008.  The solar resource data used was produced by the NREL

Climatological Solar Radiation model in 2007.  

Consistent with the June 2014 proposed rule, the Agency also includes renewable energy targets for

Puerto Rico with the inclusion of 2012 hydroelectric generation. These data are presented in the technical

files to this TSD [reference RE spreadsheet files].

Building block 4 – energy efficiency

The analysis of energy efficiency for building block 4 used the proposed methodology from the June 2014

proposed rule.

                                                            

31 See footnote 6.