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Contract No. DE-AC36-08GO28308

Status and Trends in the U.S. 

Voluntary Green Power Market

(2012 Data) 

J. Heeter and T. Nicholas

National Renewable Energy Laboratory

Technical Report

NREL/TP-6A20-60210

October 2013
NREL is a national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

Operated by the Alliance for Sustainable Energy, LLC.

This report is available at no cost from the National Renewable Energy

Laboratory (NREL) at www.nrel.gov/publications.

Contract No. DE-AC36-08GO28308

National Renewable Energy Laboratory

15013 Denver West Parkway

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303-275-3000 • www.nrel.gov

Status and Trends in the U.S. 

Voluntary Green Power Market

(2012 Data) 

J. Heeter and T. Nicholas 

National Renewable Energy Laboratory

Prepared under Task Nos. SA12.0324 and SM13.1580

Technical Report

NREL/TP-6A20-60210

October 2013
NOTICE

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express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of 

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or favoring by the United States government or any agency thereof. The views and opinions of authors

expressed herein do not necessarily state or reflect those of the United States government or any agency thereof.

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Cover Photos: (left to right) photo by Pat Corkery, NREL 16416, photo from SunEdison, NREL 17423, photo by Pat Corkery, NREL 

16560, photo by Dennis Schroeder, NREL 17613, photo by Dean Armstrong, NREL 17436, photo by Pat Corkery, NREL 17721.

 Printed on paper containing at least 50% wastepaper, including 10% post consumer waste. 
iii

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Acknowledgments

This work was funded by the U.S. Department of Energy’s Office of Energy Efficiency and 

Renewable Energy. The authors thank the Strategic Programs and Solar Offices for their support 

of this work. For their thoughtful review of the document, the authors thank Stephen Capanna, 

U.S. Department of Energy; Ed Holt, Ed Holt and Associates; Ian McGowan, 3Degrees; Steve 

Mudd, Xcel Energy; and Lori Bird, Nate Blair, Elizabeth Doris, and Marguerite Kelly of the 

National Renewable Energy Laboratory (NREL), as well as Mike Meshek of NREL for his 

editorial support. Finally, the authors thank the many green power marketers and utility contacts 

who provided the information summarized in this report. 

Additional information on green power market trends and activities can be found on the 

Department of Energy’s Green Power Network website at greenpower.energy.gov. 
iv

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

List of Acronyms

EIA Energy Information Administration

EPA Environmental Protection Agency

ERCOT Electric Reliability Council of Texas 

kW kilowatt 

kWh kilowatt-hour 

M-RETS Midwest Renewable Energy Tracking System

MW megawatt

MWh megawatt-hour 

NC-RETS North Carolina Renewable Energy Tracking System 

NREL National Renewable Energy Laboratory 

PJM-GATS PJM-Generation Attribute Tracking System 

PUC public utility commission 

REC renewable energy certificate

RPS renewable portfolio standard

SREC solar renewable energy certificate

WREGIS Western Renewable Energy Generation Information 

System
v 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Executive Summary

Voluntary green power markets are those in which consumers and institutions voluntarily 

purchase renewable energy to match their electricity needs. Voluntary action provides a revenue 

stream for renewable energy projects and raises consumer awareness of the benefits of renewable 

energy. These markets continued to exhibit growth and stimulate renewable energy development 

in 2012. Based on our review of the voluntary market, we identified the following market trends:

• In 2012, total retail sales of renewable energy in voluntary purchase markets exceeded 

48 million megawatt-hours (MWh) and represented approximately 1.3% of total U.S. 

electricity sales. These figures represent a capacity equivalent of approximately 

17,000 MW. From 2010 to 2012, total green power market sales increased by 36%, a 

compound annual growth rate of 17% (Figure ES-1). 

Figure ES-1. Estimated annual voluntary sales by market sector, 2006–2012

a Voluntary sales for 2011 are estimated as the mid-point of 2010 and 2012 sales.

• Wind energy continues to provide the most renewable energy to voluntary markets, at 

80.1% of total green power sales, followed by landfill gas and biomass (12.8%), 

hydropower (6.2%), solar (0.6%), and geothermal (0.3%). The percentage of solar used in 

the voluntary market increased from 0.2% to 0.6% and represents about 2% of sales in 

utility green pricing programs. 

• Utility green pricing sales exhibited estimated growth of 5% in 2012, similar to growth in 

2010 and 2009. 

• In 2012, 10 new community solar projects were introduced, and as of July 2013, an 

additional 6 programs had begun. The capacity of existing community solar projects 

totals more than 14 MW, with an additional 13 MW of projects under development. 

• Competitive markets saw slower growth than in previous years, increasing at a compound 

annual growth rate of 6% from 2010 to 2012. Some of the downturn may be due to 

0

10

20

30

40

50

60

2006 2007 2008 2009 2010 2011a 2012

Millions of MWh

Unbundled Renewable Energy

Cerficiate (REC) Markets

Competitive Markets

Utility Green Pricing

a 
vi 

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at www.nrel.gov/publications.

declining voluntary sales in Texas. In 2012, the renewable portfolio standard requirement 

in Texas increased. Renewable energy certificate (REC) prices in Texas also increased, 

indicating a potential shortage of supply for the voluntary market. 

• REC markets were the fastest growing and largest market segment, increasing at a 

compound annual growth rate of 25% from 2010 to 2012. The REC market appears to 

have rebounded from 2010 when it only grew 6% compared to 2009. 

• Nearly 1.9 million customers purchased green power in 2012. The number of customers 

purchasing unbundled RECs nearly doubled, driven primarily by residential customers. 

• Wholesale RECs used in voluntary markets declined from around $5/MWh in 2009 to 

less than $1/MWh in 2010 through mid-2013. In July 2013, nationally sourced voluntary 

RECs increased to more than $1/MWh, as the market in Texas began to tighten. 

• Overall, the voluntary green power market continues to grow, exceeding 48 million MWh 

in 2012, with nearly 1.9 million customers participating. 
vii 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table of Contents

Acknowledgments ..................................................................................................................................... iii

List of Acronyms........................................................................................................................................ iv

Executive Summary.................................................................................................................................... v

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

2 Voluntary Green Power Market ........................................................................................................... 6

2.1 Voluntary Market Sales ................................................................................................................... 6

2.1.1 Utility Green Pricing Sales ............................................................................................. 10

2.1.2 REC and Competitive Market Sales ............................................................................... 11

2.1.3 Residential and Nonresidential Customer Sales ............................................................. 12

2.1.4 Capacity Equivalent of Green Power Sales .................................................................... 13

2.2 Voluntary Market Customer Participation..................................................................................... 14

2.2.1 Utility Green Pricing Participation.................................................................................. 16

2.2.2 Competitive Market Participation................................................................................... 16

2.2.3 Unbundled Voluntary REC Market Participation ........................................................... 17

2.3 Voluntary Market Products and Premiums.................................................................................... 17

2.3.1 Utility Green Pricing Products and Premiums................................................................ 17

2.3.2 Unbundled REC and Competitive Market Products and Pricing.................................... 19

2.4 Green Pricing Marketing and Administrative Expenses................................................................ 21

3 REC Tracking Systems ...................................................................................................................... 25

4 REC Pricing in Voluntary and Compliance Markets ....................................................................... 30

5 Community and Crowdfunded Solar................................................................................................ 35

5.1 Intersection of Community Solar, Net Metering, and Green Pricing Programs ............................ 37

5.2 Crowdfunding Solar....................................................................................................................... 39

6 Interest of Large Consumers in New Voluntary Options ............................................................... 40

7 Lessons from Large Green Pricing Programs................................................................................. 43

7.1 Product History .............................................................................................................................. 43

7.2 Pricing............................................................................................................................................ 44

7.3 Customers ...................................................................................................................................... 45

8 Conclusions and Observations......................................................................................................... 47

References................................................................................................................................................. 48

Appendix A. Leading Purchasers in the EPA Green Power Partnership............................................ 50

Appendix B. Estimated U.S. Green Pricing Customers and Sales by State ....................................... 52

Appendix C. Top 10 Utility Green Pricing Programs............................................................................. 56
viii

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List of Figures

Figure ES-1. Estimated annual voluntary sales by market sector, 2006–2012............................................ v

Figure 1. Comparison of compliance and voluntary markets for new renewable energy, 2005–2012......... 4

Figure 2. Estimated annual voluntary sales by market sector, 2006–2012.................................................. 8

Figure 3. Utility green power and competitive market sales by purchaser’s state, 2011.............................. 9

Figure 4. Estimated green power sales by renewable energy source, 2012.............................................. 10

Figure 5. Residential and nonresidential voluntary sales, 2006–2012 ....................................................... 13

Figure 6. Trends in utility green pricing premiums, 2002–2012.................................................................. 19

Figure 7. Total retail sales of Green-e Energy certified renewable energy, 1998–2012 ............................ 20

Figure 8. Estimated average marketing and administrative expenses ....................................................... 21

Figure 9. Participation rate compared to marketing and administrative expenses ..................................... 22

Figure 10. Participation rate compared to marketing and administrative expenses per customer............. 23

Figure 11. Median marketing and administrative expenses as a percentage of green power premium 

revenue................................................................................................................................................. 24

Figure 12. Renewable energy tracking systems in North America............................................................. 26

Figure 13. Green-e eligible retirements in tracking systems....................................................................... 28

Figure 14. Compliance and voluntary retirements in ERCOT, 2007–2013 ................................................ 29

Figure 15. Voluntary REC prices, January 2008–July 2013....................................................................... 30

Figure 16. Compliance market (Tier 1) REC prices, January 2008–July 2013 .......................................... 32

Figure 17. Compliance market SREC spot prices, August 2009–August 2013.......................................... 33

Figure 18. Community solar program cumulative capacity (kW) ................................................................ 36

Figure 19. Non-utility off-takers of wind ...................................................................................................... 41

Figure 20. Growth in the EPA Green Power Partnership, 2006–July 2013................................................ 42

 

List of Tables

Table 1. Comparison of Voluntary Support Mechanisms ............................................................................. 3

Table 2. Estimated Annual Voluntary Sales (Millions of MWh) by Market Sector, 2006–2012a................... 7

Table 3. Location of Utility Green Power Supply, 2012 .............................................................................. 11

Table 4. Contract Length by Type of Procurement, 2012........................................................................... 11

Table 5. Estimated Cumulative Renewable Energy Capacity (MW) Supplying Green Power Markets, 

2008–2012............................................................................................................................................ 14

Table 6. Estimated Cumulative Green Power Customers by Market Segment, 2006–2012...................... 15

Table 7. Export/Import Capability of REC Tracking Systems ..................................................................... 27

Table 8. Utilities Reporting to EIA with Most PV Net Metering Customers, 2011....................................... 38

Table 9. Net Metering Customers at Utilities Reporting to EIA with Most Green Power Customers, 2011 38

Table A-1. Top 25 Purchasers in the EPA Green Power Partnership Program, July 3, 2013.................... 50

Table B-1. Estimated U.S. Green Pricing Customers and Programs by State, 2010 and 2011................. 52

Table B-2. Estimated U.S. Green Pricing Customers by Customer Class, 2002–2011 ............................. 54

Table B-3. EIA Estimated U.S. Green Pricing Sales (MWh) by State, 2011 .............................................. 55

Table C-1. Green Pricing Program Renewable Energy Sales, December 2012........................................ 56

Table C-2. Green Pricing Program Total Number of Customer Participants, December 2012 .................. 56

Table C-3. Green Power Sales as a Percentage of Total Retail Electricity Sales (kWh), December 2012 57

Table C-4. Price Premium Charged for New, Residential Customer-Driven Renewable Power, December 

2012...................................................................................................................................................... 57

Table C-5. Customer Participation Rate, December 2012 ......................................................................... 58
1 

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at www.nrel.gov/publications.

1 Introduction

“Voluntary” markets for renewable energy, or “green power” markets, are those in which 

consumers and institutions voluntarily purchase renewable energy to match their 

electricity needs. Entities can voluntarily purchase renewable energy through utility green 

power programs and green power marketing activities in competitive electricity markets, 

as well as in unbundled renewable energy certificate (REC) markets. RECs are present in 

all of these types of products, but in some cases the RECs are bundled at the wholesale 

level with electricity and provided to the consumer, while in others, entities may purchase 

RECs at retail separate from electricity. All of these approaches are covered in this 

report: 

• Utility green pricing (regulated utility markets)—Utility green pricing 

programs began in the early 1990s when a few utilities offered options to their 

customers. These programs continue to be offered by utilities in traditionally 

regulated electricity markets. Today, more than 860 utilities offer green power 

programs to their customers. As a result, more than half of all U.S. electricity 

customers have an option to purchase some type of green power product directly 

from a retail electricity provider. In utility green pricing programs, RECs are 

obtained by the utility and offered to customers. Utilities differ in how they 

procure RECs for their green pricing programs but often enter into power 

purchase agreements for the energy and RECs. In other cases, they may procure 

unbundled RECs. 

• Competitive green power (competitive utility markets)—In states with 

competitive (or restructured) retail electricity markets, electricity customers can 

often buy electricity generated from renewable sources by switching to an 

alternative electricity supplier that offers green power. In some of these states, 

default utility electricity suppliers offer green power options to their customers in 

conjunction with competitive green power marketers so that switching is not 

required. More than a dozen states that have opened their markets to retail 

competition have experienced some green power marketing activity.1

• Voluntary unbundled REC market (separate from electricity)—Whether or 

not customers have access to a green power product from their retail power 

provider, they can purchase green power through unbundled RECs. More than 25 

companies offer unbundled RECs to retail customers via the Internet, and a 

number of other companies market RECs solely to commercial and wholesale 

customers.2

 

1 States with competitive offerings include Connecticut, Delaware, Illinois, Maine, Maryland, 

Massachusetts, Michigan, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, and Texas. 

Washington, D.C. also has green power marketing activity.

2 For a current list of companies offering voluntary REC products, see the Department of Energy’s Green 

Power Network website: http://apps3.eere.energy.gov/greenpower/markets/certificates.shtml?page=2. 
2 

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at www.nrel.gov/publications.

In addition to these voluntary market segments, numerous additional means of 

procurement are emerging. In some cases, new models are providing a hedge against 

future electricity prices or other benefits, but they do not provide the environmental 

benefit to the customer (i.e., the REC is transferred to another party). Emerging models 

include: 

• Community solar. Community solar programs allow utility customers to 

purchase a portion of a larger solar project. Customers then receive the benefits of 

the energy that is produced by their share. Structures differ, but a common model 

is for the RECs to be transferred to the utility to meet compliance with a 

renewable portfolio standard (RPS). More than 40 community solar projects 

totaling approximately 14 MW exist in the United States. 

• Large direct project investment and “crowdfunding.” Large organizations, 

such as Google, have made direct investments in renewable projects. Google’s 

investments have supported more than 1,000 MW of wind and solar in the United 

States. On a smaller scale, crowdfunding, which allows individuals to contribute 

to project financing, has supported solar development. Mosaic, a crowdfunding 

platform for solar, has invested in around 4 MW of solar. Project investments, 

whether large or small, typically do not convey the RECs to the investors. 

Investors also do not receive the power produced by the project. 

• Direct power purchase agreements and large commercial customer green 

power rates. A number of corporations, universities, and others have negotiated 

power purchase agreements for renewable energy. Importantly, not all states 

allow for power purchase agreements. In addition, a few utilities have proposed 

new tariffs that would allow large utility customers to purchase renewable energy 

from a specific facility in the utility service territory, instead of negotiating a 

power purchase agreement directly. 

• On-site solar/solar leasing. On-site solar systems, which in some states are 

primarily owned by third parties, allow customers to provide a location for a solar 

system and potentially see savings on electricity expenditures. In most cases 

outside of California, the RECs from on-site solar systems are used by the electric 

utility to meet RPS compliance.

Table 1 outlines these emerging models and highlights the relative market sizes compared 

to utility green power, competitive suppliers, and unbundled RECs. While the emerging 

methods have seen large growth in recent years, the capacity they support as of 2012 was 

much less than is supported by utility green pricing, competitive suppliers, and unbundled 

REC market. In some cases, markets do overlap, making it difficult to compare true 

market sizes.
3 

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Table 1. Comparison of Voluntary Support Mechanisms

Support Mechanism REC Ownership Value Proposition Market Size (2012)

Utility green power or 

competitive supplier

With customer Match electricity use with renewables; 

corporate sustainability goals

2,400 MW

Unbundled RECs With customer Match electricity use with renewables; 

corporate sustainability goals

14,900 MW

On-site photovoltaics (PV) Outside of California, 

typically goes to utility

Support renewables development by 

providing a host site; potentially lower 

electricity bill

1,416 MW residential, 2,897 MW nonresidentiala

Community solar Varies, currently nearly 

always to utility

Support local solar development; 

potentially lower electricity bill 

14 MW 

Power purchase 

agreements/

large commercial customer 

green power rates

Varies Corporate sustainability goals; support 

new renewables; potential financial 

returns

Unknown; likely to be captured in estimate of utility 

green power, competitive supplier, or unbundled 

REC segment.

Direct project investment Typically with project 

developer 

Support new renewables; potential 

financial return 

1,115 MW (Google)b

Crowdfunding (small-scale 

direct project investment)

Varies Support new solar development; 

potential financial return

4 MW (Mosaic)c

 

a SEIA and GTM (2013)

b As of October 2013. Google (2013)

c As of October 2013. Mosaic (2013)
4 

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Through 2009, the voluntary market exceeded or nearly equaled the compliance market 

for new renewables (Figure 1). However, the compliance market increased dramatically 

in 2010 because many states set significant targets for 2010.3

 By 2015, compliance 

demand for new renewable energy due to existing state RPS policies is expected to be 

about 140 million megawatt-hour (MWh) (Barbose 2013). 

Figure 1. Comparison of compliance and voluntary markets for new renewable energy, 

2005–2012 

a Voluntary sales for 2011 are estimated as the mid-point of 2010 and 2012 sales.

Estimates of compliance market demand assume that RPS targets are fully met.

Source: Barbose (2013)

The data on voluntary market trends presented in this report were formerly reported in

Market Brief: Status of the Voluntary Renewable Energy Certificate Market (2011 Data)

(Heeter et al. 2012) and Status and Trends in U.S. Compliance and Voluntary Renewable 

Energy Certificate Markets (2010 Data) (Heeter and Bird 2011).4

 Voluntary market data 

are based on figures provided to the National Renewable Energy Laboratory (NREL) by 

utilities and independent renewable energy marketers. NREL also supplements this data 

with information from the Energy Information Administration (EIA), REC certifiers, 

REC tracking systems, and press releases describing large voluntary green power 

 

3 Although RPS policies generally allow pre-existing renewable energy generation sources (i.e., those 

installed before the adoption of the RPS) to meet their targets, the estimates presented here reflect only the 

amount of new renewable energy generation that these policies are expected to stimulate. These figures are 

compared to the voluntary market estimates because voluntary markets primarily support generation from 

new renewable energy projects (i.e., those installed after voluntary green power markets were established). 

Estimates of compliance market demand assume that RPS targets are fully met. 

4 Voluntary market data from previous years are captured in earlier versions of this report, including Heeter 

et al. (2012), Heeter and Bird (2011), Bird and Sumner (2010), Bird et al. (2009), and Bird et al. (2008).

 -

 10

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 30

 40

 50

 60

 70

 80

 90

2006 2007 2008 2009 2010 2011a 2012

Millions of MWh

Voluntary

Compliance (new

renewables)

a 
5 

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at www.nrel.gov/publications.

purchases. Because data cannot be obtained from all market participants, the estimates 

presented here likely underestimate the market size. Because obtaining data on 

competitive markets is particularly challenging due to market sensitivity and rapid 

changes in offerings, estimates of the competitive market are more uncertain.

This report documents REC activities and trends in the United States, presenting data and 

analysis on voluntary market sales and customer participation, products and premiums, 

green pricing marketing, and administrative expenses. The report also details REC 

tracking systems, REC pricing in voluntary and compliance markets, community and 

crowd-funded solar, large consumer interest in voluntary options, and lessons from 

successful green pricing programs. 
6 

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at www.nrel.gov/publications.

2 Voluntary Green Power Market Voluntary consumer purchases of renewable energy represent a market support 

mechanism for renewable energy development. In the early 1990s, a small number of 

U.S. utilities began offering “green power” options to their customers. Since then, these 

products have become more prevalent, offered by traditional utilities and renewable 

energy marketers operating in states that have introduced competition into their retail 

electricity markets or offering RECs online. Today, more than half of all U.S. electricity 

customers have an option to purchase some type of green power product directly from a 

retail electricity provider, while all consumers have the option to purchase RECs. 

2.1 Voluntary Market Sales

Overall, retail sales of renewable energy in voluntary green power markets exceeded 48

million MWh and represented approximately 1.3% of total U.S. electricity sales in 2012.5

Based on the sales data we present in this report, we estimate the market value of green 

power sales (the above-market cost of the green power) in 2012 to be between $208 

million and $366 million.6

Green power sales (in megawatt-hours) increased by 37% between 2010 and 2012, with a 

compound annual growth rate of 26% since 2006 (see Table 2 and Figure 2). A market 

estimate for 2011 was not made, thus, data here are presented as changes between 2010 

and 2012 or as compound annual growth rates between 2010 and 2012. The unbundled 

REC markets represent 64% of all green power sales.

7 The unbundled REC market 

rebounded strongly in 2012 from 2010, after growing only 6% from 2009 to 2010. The 

competitive market sector growth has slowed, likely due to slow growth in Texas as a 

result of increased RPS retirements in that state. Annual growth rates in the utility green 

pricing sector continued to decline in 2012. 

 

5 U.S. electricity sales totaled 3,750 million MWh in 2011 (EIA 2013). The remaining renewable energy 

generation is rate-based by utilities or used to meet RPS policies. 6 Estimates of the above-market value of green power sales are determined by multiplying green power 

sales in megawatt-hours in three subsectors (utility green pricing programs, residential competitive 

markets, and nonresidential competitive and REC market) by a low and high estimate of prices in each of 

the sectors.

7 The REC sales figures reflect sales to end-use customers separate from electricity. RECs bundled with 

electricity and sold to end-use customers through utility green pricing programs or in competitive 

electricity markets are counted in other categories. 
7 

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at www.nrel.gov/publications.

Table 2. Estimated Annual Voluntary Sales (Millions of MWh) by Market Sector, 2006–2012a 

Market Sector 2006 2007 2008 2009 2010 2012

Utility Green Pricing 3.4 4.2 4.8 5.2 5.4 6.0

% Change from previous year 39% 23% 15% 7% 5% 5%f

% Nonresidential 38% 38% 45% 45% 46% 48%

Competitive Markets 1.7b 3.2 5.3c 8.3c 10.4 11.6

% Change from previous year -20%d 88% 64%c 56%c 25% 6%f

% Nonresidential 41% 44% 32% 40% 35% 38%

Unbundled REC Marketse 6.8 10.6 15.6 18.7 19.8 31.0

% Change from previous year 75% 55% 49% 20% 6% 25%f

% Nonresidential 99% 98% 99% 99% 99.8% 98%

Retail Total 11.9 18.0 25.7c 32.2c 35.6 48.6

% Change from previous year 40% 51% 43%c 25%c 11% 17%f

% Nonresidential 73% 75% 75% 76% 73% 78%

a Includes sales of new and existing renewable energy; totals and growth rates may not compute 

due to rounding. b

 Sales figures for 2006 may be underestimated because of data gaps. c

 Competitive market sales for 2008 and 2009 were revised upward in this report to reflect data 

on green power markets in Texas published by the Texas public utility commission (PUC) in 2010 

and 2011. For historical reports, see https://www.texasrenewables.com/reports.asp (Accessed 

October 14, 2013.

d 2006 number is likely underestimated because of data gaps. e Includes only RECs sold to end-use customers separate from electricity (unbundled) f

Compound annual growth rate for 2010–2012; Changes from 2010 to 2012 were 11% for utility 

green pricing, 12% for competitive markets, 56% for unbundled REC markets, and 37% total.
8 

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at www.nrel.gov/publications.

Figure 2. Estimated annual voluntary sales by market sector, 2006–2012 

a Voluntary sales for 2011 are estimated as the mid-point of 2010 and 2012 sales.

Utility green power and competitive market sales are predominant in certain states.8 State 

data on utility and competitive market sales for 2011 are publically available from the 

EIA (Figure 3). EIA collects data directly from utilities and marketers as part of its Form 

861; however, it should be noted that because not all competitive retailers report to EIA, 

these data underestimate sales, particularly in states with competitive retail markets.9 The 

top states in terms of total sales include Texas, Oregon, New York, California, and 

Washington.

 

8 Data on the geographic location of purchasers of unbundled RECs is not available from EIA. 9 According to EIA, Form EIA-861 is completed by “electric utilities, wholesale power marketers 

(registered with the Federal Energy Regulatory Commission), energy service providers (registered with the 

States), and electric power producers. Responses are collected at the business level (not at the holding 

company level).” (EIA 2011a).

0

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20

30

40

50

60

2006 2007 2008 2009 2010 2011a 2012

Millions of MWh

Unbundled Renewable Energy

Cerficiate (REC) Markets

Competitive Markets

Utility Green Pricing

a 
9 

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at www.nrel.gov/publications.

Figure 3. Utility green power and competitive market sales by purchaser’s state, 2011

Source: EIA 2012 

> 500,000

200,000–500,000

100,000–200,000

10,000–100,000

1,000–10,000

100–1,000

< 100

2011 Green Power 

Sales by 

Purchaser’s State 
10 

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National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

In terms of resources used, wind energy represented 80.1% of the total green power sales 

reported here, followed by biomass energy sources, including landfill gas (12.8%), 

hydropower (primarily low impact or small hydropower, 6.2%), solar (0.6%), and 

geothermal (0.3%) (Figure 4). Solar surpassed geothermal in 2012 and provided about 

2% of the supply for utility green pricing programs.

Figure 4. Estimated green power sales by renewable energy source, 2012

 

2.1.1 Utility Green Pricing Sales

Utility green pricing sales continue to exhibit some growth, but growth has slowed in 

recent years. Collectively, utilities in regulated electricity markets sold about 6.0 million 

MWh of green power to customers in 2010 (Table 2). Green pricing program sales to all 

customer classes grew by a compound annual growth rate of 5% between 2010 and 2012, 

exhibiting growth that was similar to what was seen between 2009 and 2010 and which 

was markedly slower than growth from previous years, when rates ranged from 15% to 

39% (Table 2). While some programs continue to grow robustly, the slower growth in 

this sector may be a result of many factors, such as the decline in new utility program 

development, decline in the economy, decreased emphasis on marketing programs, 

switching by nonresidential participants from utility green pricing to unbundled REC 

purchasing, or increased focus by nonresidential participants on on-site projects. 

In utility green pricing programs, the average residential purchase in 2012—

approximately 5,800 kilowatt-hours per year (kWh/year)—surpassed the high seen in 

2008 of approximately 5,500 kWh/year, increasing about 7% from 2010. The average 

nonresidential purchase increased nearly 60% from 2010, rising to about 

227,000 kWh/year in 2012. 

In 2012, green pricing sales represented a small proportion of a utility company’s overall 

energy sales. On average, renewable energy sold through green pricing programs in 2012 

represented 1.2% of total utility electricity sales of the utilities offering green pricing 

Wind

80.10%

Landfill gas and 

biomass

12.79%

Hydropower 

6.19%

Solar 

0.62%

Geothermal

0.30%
11 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

programs (on a megawatt-hour basis). Top performing programs saw rates ranging from 

2.8% to 23.9%. Due to a large nonresidential purchase, one small utility reported that 

23.9% of its total retail electricity sales were green power sales (see Appendix C). 

In 2012, utility green power supply typically came from within a utility’s region (81%)

(Table 3).

10 About half of utility procurement (56%) came from unbundled RECs, in 

contracts of fewer than five years (Table 4). The second largest supply came from RECs 

bundled with electricity (40%), of which the vast majority was contracted for 11 or more 

years (92%). Smaller portions of utility green power supply came from systems owned by 

the utility (3%) or was purchased from utility customers (e.g., from on-site solar systems) 

(1%). 

Table 3. Location of Utility Green Power Supply, 2012

Within Service Territory Within State Within Region

24% 53% 81%

Table 4. Contract Length by Type of Procurement, 2012

Contract Length Unbundled 

RECs

RECs Bundled 

with Electricity

Owned by 

Utility

RECs Produced by 

Utility Consumers 

≤1 year 39.30% 0% 0% 0%

2–5 years 43.20% 0% 0% 41%

6–10 years 0.20% 8% 1% 45%

11+ Years 0.30% 92% 99% 15%

Percent of total 

procurement 56% 40% 3% 1%

2.1.2 REC and Competitive Market Sales

In REC markets and competitive green power markets (i.e., in states with retail 

competition), an estimated 42.6 million MWh of renewable energy was sold to retail 

customers in 2012 (Table 2). Overall, 2012 was again a mixed year for both REC 

marketers and competitive marketers; some saw large gains in sales, while others saw 

sales remain flat or even down compared to 2010. 

In competitive electricity markets, an estimated 11.6 million MWh were sold as a 

bundled green power product in competitive electricity markets—a 12% increase from 

2010. Due to the challenges of obtaining data from competitive marketers and the lack of 

current data on the Texas market, which has seen a dramatic increase in the number of 

 

10 Utilities were asked to self-define region. Typically the region was considered to be the regional 

transmission organization or independent system operator boundary, or in the Western U.S., the Western 

Electricity Coordinating Council.
12 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

companies offering renewable energy products in recent years, the sales figures for the 

competitive market are underestimated. 

In previous years, voluntary retirements in the Electric Reliability Council of Texas

(ERCOT) surpassed compliance retirements, and they were increasing year to year. 

However, in 2012, voluntary retirements in ERCOT declined from 15.3 million MWh to 

9.5 million MWh.11 

Retail REC sales (unbundled RECs) increased by 56%, reaching 31 million MWh in 

2012. This represents a substantially greater growth than in 2010, which saw only 6% 

annual growth, compared to a compound annual growth rate for 2010–2012 of 25% 

(Table 2). The Environmental Protection Agency’s Green Power Partnership, which 

tracks how participants purchase renewable energy, saw those purchases increase by 17% 

between 2011 and 2012. Unbundled REC purchases account for 76% of all purchases 

made by partners in the Green Power Partnership. 

2.1.3 Residential and Nonresidential Customer Sales

Sales to nonresidential customers continued to outpace those to residential customers, 

with 78% of all sales by volume to the nonresidential sector in 2012, slightly greater than 

in previous years (Table 2). Figure 5 delineates green power sales by customer segment. 

Residential customers played a larger role in green pricing programs and competitive 

markets than in REC markets in 2012. Residential customers accounted for 52% of green 

pricing sales and 62% of competitive market sales but only 2% of unbundled REC sales 

(Table 2). 

Nearly all unbundled REC sales on a megawatt-hour basis were to business and 

institutional customers. Generally, nonresidential customers find REC-only products 

attractive because of their flexibility and the greater potential for cost savings they offer 

because they can be sourced from renewable energy projects in more favorable resource 

locations; also, transaction costs may be lower because the marketer and purchaser don't 

have to negotiate electricity supply. For commercial and institutional customers that 

operate facilities in multiple locations across the country, RECs may also provide a more 

efficient green power sourcing solution than working with utilities in each individual 

utility territory.12 On the other hand, residential customers may not be aware that RECs 

are available or may not understand what they convey. 

 

11 A retirement occurs when a REC is used for voluntary purposes and will no longer be traded or claimed. 

This issue is discussed further in Section 2.3.

12 For example, the EPA Green Power Partnership reports that the majority of its Top 25 partners purchase 

RECs. For more information, see www.epa.gov/greenpower. 
13 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 5. Residential and nonresidential voluntary sales, 2006–2012

a Voluntary sales in 2011 are estimated as the mid-point of 2010 and 2012 sales.

2.1.4 Capacity Equivalent of Green Power Sales

At the end of 2012, megawatt-hour sales of renewable energy in voluntary markets 

represented a generating capacity equivalent of approximately 17,300 MW, with nearly 

all of that capacity coming from new renewable energy sources (see Table 5).13,14 Since 

2007, when total renewable capacity supplying the green power market was 5,100 MW, 

the amount of renewable energy capacity serving green power markets increased more 

than three-fold.

 

13 Capacity estimates are calculated based on reported green power kilowatt-hour sales, assuming capacity 

factors for each renewable resource type. For wind, a capacity factor of 26% was assumed, 85% for landfill 

gas, 83% for biomass, 65% for geothermal, 42% for hydroelectric, and 14% for solar electric. These figures 

are based on industry data and the average capacity factors of operating plants. 14 “New” renewable energy capacity is defined here as capacity that was sourced from renewable energy 

systems that were built or repowered after January 1, 1997.

0

10

20

30

40

50

60

2006 2007 2008 2009 2010 2011* 2012

Millions of MWh

Nonresidential sales

Residential sales

73% 

75% 

75% 

76% 

73% 

75%* 

78% 

a
14 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table 5. Estimated Cumulative Renewable Energy Capacity (MW) Supplying Green Power 

Markets, 2008–2012 

2009 2010 2012

Market Total 

Capacity

New 

Capacity

Total 

Capacity

New 

Capacity

Total 

Capacity

New 

Capacity

Utility Green Pricing 1,700 1,600 1,700 1,600 2,400 2,200

Competitive Markets 

and Unbundled RECs

7,700 6,400 9,400 6,800 14,900 14,900

Total 9,400 8,000 11,200 9,400 17,300 17,200

“New” renewable energy capacity is a subset of total renewable energy capacity 

supplying green power markets. Totals may not sum due to rounding.

2.2 Voluntary Market Customer Participation 

In 2012, nearly 1.9 million electricity customers nationwide purchased green power 

products through regulated utility companies, from green power marketers in a 

competitive-market setting, or in the form of RECs (Table 6).15 This represents nearly 

flat growth from 2010, though growth varied by sector. Participation in utility green 

pricing programs and competitive markets was essentially flat, while REC market 

participation nearly doubled. Utility green pricing programs remained nearly flat over all, 

but saw a 13% decline in nonresidential participation.

 

15 It is important to note that there is greater uncertainty in our customer estimates for competitive and REC 

markets because of data limitations. For more detailed estimates by state for 2009 and 2010, see data from 

EIA 2011 in Appendix B. Generally, our estimates are consistent with the EIA estimates when adjusted for 

customers in Ohio who participated in community aggregations in 2005 and earlier. We excluded these 

customers from our estimates because they purchase products with very low renewable energy content 

(1%–2%). 
15 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table 6. Estimated Cumulative Green Power Customers by Market Segment, 2006–2012 

2006 2007 2008 2009 2010 2012

Utility Green Pricing 490,000 550,000 550,000 550,000 570,000 570,000

Residential 470,800 526,700 519,700 526,300 544,700 549,600

Nonresidential 15,500 20,200 26,100 26,000 22,900 17,200

% Residential Growth 23% 12% -1% 1% 4% 0.4%a

% Nonresidential Growth 37% 30% 29% -1% -12% -13%a

Competitive Market ~ 210,000 300,000 390,000 830,000 ~ 1,200,000 ~ 1,200,000

Voluntary REC Market ~ 10,000 > 10,000 30,000 < 20,000 > 60,000 ~110,000

Retail Total ~ 710,000 ~ 860,000 ~ 970,000 ~ 1,400,000 ~ 1,830,000 ~1,870,000

% Change ~ 22% ~ 21% ~ 13% ~ 44% ~ 25% ~2%

In some cases, estimates have been revised from those reported in previous NREL reports as updated data have become available. 

Totals may not add due to rounding. 

a

 Compound annual growth rate for 2010–2012
16 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

2.2.1 Utility Green Pricing Participation

The number of green pricing customers was nearly flat between 2010 and 2012 (Table 6), 

with residential customers increasing slightly (0.4%) and nonresidential customers 

declining by 13%.16 As in the past, a small number of green pricing programs account for 

the majority of customers, with just 10 utilities accounting for 76% of all participants (see 

Appendix C).17 From 2010 to 2012, residential participation increased by less than 1%, 

while nonresidential participation declined by nearly 25%. Nonresidential growth has 

been slowing in recent years, and absolute numbers of nonresidential participants has 

continued to decline since 2008. 

At the end of 2012, the average participation rate in utility green pricing programs among 

eligible utility customers was 2.8% with a median of 1.5%. These industry-wide rates 

have shown little change in recent years. Participation rates in top-performing programs 

have remained relatively unchanged since 2007, thought they have improved compared to 

the ranges in early years: Top-performing participation rates ranging from 6.5% to 18.2% 

in 2012, compared to a range of 3.9% to 11.1% in 2003. 

For 2012, utilities reported that an average of 8.5% and a median of 7.2% of customers 

dropped out of green pricing programs. These figures represent an increase from 2010 

when utilities reported an average of 7.0% and a median of 4.7%, but the figures are 

consistent with 2009 when utilities reported an average of 7.8% and a median of 6.3%. 

2.2.2 Competitive Market Participation

In the competitive green power market, participation was essentially flat between 2010 

and 2012. In 2012, approximately 1.2 million customers (primarily residential customers) 

participated. Because obtaining data about the competitive market is particularly

challenging, these figures likely underestimate the number of participants in competitive 

market programs. 

The Texas market saw dramatic growth in customer numbers in 2009 and 2010, but since 

then, growth has dropped off. The largest gains in 2009 and 2010 were due to one 

marketer. According to the most recent published EIA data (for 2011), the number of 

green power customers in Texas increased to 465,000 in 2011 from 412,000 in 2010 and 

316,000 in 2009 (see Appendix B).18

 

16 NREL attempted to contact all utility green pricing programs and received data directly from 

approximately 40% of programs in 2012, including all major programs. Supplemental data from EIA were 

used for the remaining programs, which are smaller and do not have a large impact on overall participant 

numbers. When possible, other sources and previously reported data were used to estimate data for gaps. 17 NREL issues five different Top 10 lists based on total sales of renewable energy to program participants, 

total number of customer participants, customer participation rates, green power sales as a fraction of total 

utility sales, and the premium charged to support new renewable energy development. These lists can be 

found in Appendix C or at http://apps3.eere.energy.gov/greenpower/markets/pricing.shtml?page=3. 18 The EIA figures include customers in both utility green pricing programs and competitive market 

programs, but they do not include all competitive retailers; therefore, these estimates underestimate the 

total number of customers but serve to show at a minimum the level of growth in Texas.
17 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

While the number of green power purchasers has expanded during the past few years in 

markets with retail competition, participation has been less consistent over time, as some 

markets have grown and then contracted. In the last few years, growth in competitive 

markets has been concentrated in Texas and a few programs in the Northeast. Data from 

EIA show that Massachusetts, Oregon and Maryland gained more than 3,000 customers 

in 2011 than they did in 2010 (see Appendix B). 

Data from EIA also show that participation in states varies greatly. According to 2011 

EIA data, more than 4% of customers in Texas are green power customers.

19 Several 

other competitive market states (Connecticut, New York, and Vermont) have seen 

participation greater than 1%. Over time, participation has generally been more volatile in 

competitive markets than in traditionally regulated markets. 

2.2.3 Unbundled Voluntary REC Market Participation

The number of REC-only buyers nearly doubled between 2010 and 2012, after seeing 

large growth in 2010. In 2012, nearly 110,000 customers were purchasing unbundled 

RECs, an increase from more than 60,000 customers in 2010. In 2012, approximately 

80% of the unbundled customers were residential customers. The large increase in 

residential unbundled REC customers in 2010 and 2012 could be a result of REC 

marketers more specifically targeting the residential sector. Often residential customers 

may not be aware of the option to purchase RECs via the Internet. The Natural Marketing 

Institute found that in 2010 only 14% of the general population was aware they could buy 

renewable power from their electric or another company, even though all consumers have 

the option to buy RECs (NMI 2011). 

While most REC buyers are residential customers, the majority of REC sales on a 

megawatt-hour basis are made to nonresidential customers due to the much larger 

purchase sizes. As a result of large nonresidential REC purchases, REC sales represent 

64% of total green power megawatt-hour sales (Table 2) and have grown dramatically in 

recent years (see Appendix A for a list of top green power purchasers). 

2.3 Voluntary Market Products and Premiums

2.3.1 Utility Green Pricing Products and Premiums

Typically, green pricing programs are structured so that customers can either purchase 

green power for a certain percentage of their electricity use (often called “percent-of-use 

products”) or in discrete amounts or blocks at a fixed price (“block products”), such as a 

100-kWh block. Most utilities offer block products but may also allow customers to buy 

green power for their entire monthly electricity use. Utilities that offer percent-of-use 

products generally allow residential customers to elect to purchase 25%, 50%, or 100% 

of their electricity use as renewable energy, while a few offer fractions as small as 10%. 

Under these types of programs, larger purchasers, such as businesses, can often purchase 

green power for some fraction of their electricity use as well. 

 

19 EIA data also include participant in utility green pricing programs. 
18 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

More recently, the concept of community solar has emerged. In community solar 

programs, customers purchase a share of a community solar system. In return, they obtain 

a proportionate share of the system output, which is credited to them on their utility bills. 

These programs are offered by utilities or third parties operating in conjunction with 

utilities. Community solar programs differ in terms of the upfront cost and return 

payment received by participants. One program, the Holy Cross Energy solar project, 

sells upfront shares for $3.15 per watt (W) and credits participants at a rate of $0.11/kWh

for producing their shares.

20 Community solar programs are addressed in depth in 

Section 5. 

In 2012, the price of green power for residential customers in utility programs ranged 

from 0.87¢/kWh below standard electricity rates to 4.61¢/kWh above standard electricity 

rates, with an average premium of 1.58¢/kWh and a median premium of 1.40¢/kWh. 

These premiums have been adjusted to account for any fuel-cost exemptions granted to 

green power program participants.21 In 2012, the 10 utility programs with the lowest 

premiums for energy derived from new renewable sources had premiums ranging from 

0.87¢/kWh (a savings) to 0.86¢/kWh. On average, residential consumers spent about 

$6.97 per month above standard electricity rates for green power through utility 

programs, which is slightly higher than expenditures in previous years of around $6.30 

(2010) and $5.40 (2009). 

Since 2002, the average price premium has dropped at a compound annual rate of 6% 

(see Figure 6). Some of this reduction can be attributed to lower market costs for 

renewable energy supplies or increased competitiveness with conventional generation 

sources. The competitiveness of wind and other renewables with conventional generation, 

as well as regional demand from state renewable energy standards, will affect premiums 

in coming years. 

 

20 For more information, see “Holy Cross Energy Launches 80 kW Community Solar Program” at 

http://apps3.eere.energy.gov/greenpower/news/news_template.shtml?id=1564 (accessed October 3, 2011). 21 For example, a small number of utilities exempt green pricing customers from monthly or periodic fuel 

charges imposed to pay higher-than-expected fossil fuel costs. For a detailed discussion of this topic, see 

Bird et al. (2008). 
19 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 6. Trends in utility green pricing premiums, 2002–2012 

2.3.2 Unbundled REC and Competitive Market Products and Pricing

Green power products offered in electricity markets with retail competition tend to differ 

from those offered by utilities in regulated markets, as they are more likely to be sourced 

from RECs because suppliers may be less able to enter into long-term contracts with 

generators. In addition, price premiums may fluctuate more frequently. 

Initially, green power marketers in competitive markets were often forced to offer 

existing renewable energy sources because of a lack of new renewable energy supplies, 

but most marketers now offer primarily new renewable energy. This movement toward 

increased reliance on new sources has also been encouraged by green power product 

certification programs, which set standards for product quality and have required 

increasing amounts of new renewable energy. Both Green-e Energy22 and the EPA Green 

Power Partnership23 currently operate on a 15-year rolling window for defining a “new” 

facility, meaning that projects must have come online within 15 years prior to the sale of 

the green power in order to be classified as new. 

The price premium charged for competitive-market products depends on several factors, 

including the price of default service and the cost of renewable energy generation 

available in the regional market. In recent years, some marketers (e.g., in Texas) have 

charged prices close to or even below the prevailing cost for system power; others have 

offered fixed-price products, providing customers with protection against increasing 

prices for a specified period of time—usually one year. 

Competitively marketed green power products generally carry a price premium between 

1¢/kWh and 2.5¢/kWh for residential and small commercial customers, although 

 

22 Administered by the Center for Resource Solutions, the Green-e Energy program certifies retail and 

wholesale green power products that meet its environmental standards, product content, and marketing 

standards. For details on the Green-e Energy National Standard, see the Green-e website at green-e.org. 23 See the EPA’s Green Power website at epa.gov/greenpower. 

1.0

1.5

2.0

2.5

3.0

Residential premium (cents/kWh)

Average

Median
20 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

offerings have ranged from small discounts to a premium of about 10¢/kWh in recent 

years. For utility/marketer programs offered in states with retail competition, the average 

price premium for green power was about 2.3¢/kWh in 2012. In addition, price premiums 

can change frequently with changes in market conditions. Higher-priced products often 

contain a larger fraction of new renewable energy content or resources that are more 

desirable to consumers, such as new wind and solar.

Retail prices charged for REC products typically range from about 0.5¢/kWh to 

2.5¢/kWh for residential and small commercial customers. In most cases, large 

commercial customers are able to negotiate lower prices. Nearly all REC products are 

sourced from “new” renewable energy generation projects as a result of product 

certification requirements.

Because RECs are generally not subject to the same regulatory scrutiny as electricity and 

mandatory renewable requirements, REC buyers often seek certification out of concerns 

about double counting and to ensure a level of oversight and auditing. Buyers may also 

be interested in using the Green-e Energy label in communication materials. 

Figure 7 shows Green-e Energy certified retail transactions from 1998 to 2012. Green-e 

Energy certified 35.9 million MWh of retail transactions in 2012 (Terada 2013). This 

represents an increase of 29% from 2011. 

Figure 7. Total retail sales of Green-e Energy certified renewable energy, 1998–2012 

Source: Terada 2013 

The Green-e Energy program also certifies wholesale renewable energy transactions, 

which totaled 15.7 million MWh in 2012. It is important to note that 6.5 million MWh 

sold in certified wholesale transactions were resold in Green-e Energy certified retail 

transactions. The remaining 9.1 million MWh were sold in non-Green-e Energy certified 

transactions, most likely to utilities and electric service providers, power marketers, or 

0

5

10

15

20

25

30

35

40

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Millions of MWh of Green-e Energy 

Certified Retail Sales

Green Pricing

Competitive Electricity

RECs
21 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

retail customers. In total, Green-e Energy certified 42.4 million MWh of unique 

transactions in 2012.

2.4 Green Pricing Marketing and Administrative Expenses

Retail product pricing typically reflects the costs involved in attracting and servicing 

retail customers to some degree, though data on marketing and administrative expenses 

are challenging to obtain. This section highlights marketing and administrative expenses 

for utility green pricing programs and examines their relationship to utility size, 

participation rate, and green power premium revenue. While these figures help illustrate 

trends in marketing and administrative expenses, each utility program will face unique 

circumstances when deciding how much to spend on marketing and administration. For a 

more detailed look at marketing and administrative expenses, see Friedman and Miller 

(2009). 

Utilities in some cases are working with third parties to market their programs. In 2012, 

33% of programs that reported to NREL indicated that they were working with a 

third party. 

Marketing and administrative expenses increase with the size of the utility (measured as 

the number of eligible green power customers in their service territory) (Figure 8). 

Figure 8. Estimated average marketing and administrative expenses

While Figure 8 shows that larger utilities spend more on marketing and administration, 

these increased expenses do not necessarily correlate to increased green power program 

participation. Large utilities may spend more on marketing in dollar terms because they 

have a larger territory to reach out to. Also, in some cases, for example, a new program 

operating in a large service territory may spend heavily on marketing and administration 

and see large increases in customer participation, but may not see large increases in the 

participation rate for a number of years. Figure 9 shows that a majority of surveyed 

utilities (59%) spent less than a combined $50,000 on marketing and administration; yet, 

$4,999 

$28,845 

$69,090 

$147,499 

$233,999 

$7,082 $14,374 

$51,666 

$155,999 

$197,999 

 $-

 $50,000

 $100,000

 $150,000

 $200,000

 $250,000

<25

(n=14)

25-100

(n=16)

100-500

(n=13)

500-1000

(n=6)

>1000

(n=10)

Eligible Residential Customer Base (thousands)

Marketing Expenditures

Administrative Expenditures
22 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

the participation rate among these utilities varies from .03% to more than 5% (some data 

points suppressed to preserve confidentiality). The disconnection between participation 

and expenses is further highlighted by examining companies with less than 1% 

participation (52% of all companies surveyed); these companies had expenses ranging 

from $4,999 to more than $500,000,24 yet had no significant difference in participation 

rate. 

Figure 9. Participation rate compared to marketing and administrative expenses

Programs indicating $500,000+ in their response for either marketing or administrative 

expenses are captured here as $500,000.

Some data points were suppressed to preserve confidentiality. 

Figure 10 shows the participation rate based on marketing and administrative expenses 

per green power customer. This allows participation rates to be compared with less 

weight placed on company size. As shown in Figure 7, total marketing and administrative 

expenses increase as the total customer base increases; however, Figure 10 shows that no 

trend has been established linking increased expenses per customer to increased 

participation rate. 

 

24 NREL’s questionnaire asked participants how much was spent on marketing expenses, and then 

separately, how much was spent on administrative expenses. Answer options for both questions were $0; 

$1-$9,999; $10,000-$49,999; $50,000-$99,999; $100,000-$199,999; $200,000-$299,999; $300,000-

$399,999; $400,000-$499,999; and $500,000+. Because of the $500,000+ option, it is not certain exactly 

what some participants spent, only that it is was greater than $500,000.

$0

$100,000

$200,000

$300,000

$400,000

$500,000

$600,000

$700,000

$800,000

$900,000

0% 1% 2% 3% 4% 5%

Combined Marketing and Administrative 

Expenses

Participation Rate
23 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 10. Participation rate compared to marketing and administrative expenses 

per customer

This figure excludes seven outlier data points. Those outliers show expenses per 

customer ranging between $833 and $2,500; all with participation rates of 1% or less. 

Programs indicating $500,000+ in their response for either marketing or administrative 

expenses are captured here as $500,000.

Some data points were suppressed to preserve confidentiality. 

Figure 11 shows marketing and administrative expenses as a percentage of green power 

premium revenues. Although it is among the most common metrics, expressing 

expenditures as a percentage of revenues is somewhat problematic, because it is easy to 

overlook the fact that a lower expenditure percentage may be as much a function of a 

relatively high premium and high program revenues (the denominator in the equation) as 

the marketing expenditure itself (the numerator in the equation) (Friedman and Miller 

2009). 

$0

$50

$100

$150

$200

$250

$300

$350

$400

$450

$500

0% 1% 2% 3% 4% 5%

Combined Marketing and Administrative 

Expenses per Customer

Participation Rate
24 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 11. Median marketing and administrative expenses as a percentage of green power 

premium revenue

Percentages calculated based on green power premium, not total electricity rate.

48%

12% 6%

15%

5%

135%

21%

10% 12% 7%

0.00%

20.00%

40.00%

60.00%

80.00%

100.00%

120.00%

140.00%

160.00%

<25

(n=14)

25-100

(n=16)

100-500

(n=13)

500-1000

(n=6)

>1000

(n=10)

Eligible Residential Customer Base (thousands)

Marketing Expense

Administrative Expense
25 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

3 REC Tracking Systems

States and others have created REC tracking systems to verify compliance with RPS 

targets. These electronic tracking systems ensure that RECs are only “retired” (used to 

meet compliance) once by assigning a unique serial number to each megawatt-hour of 

renewable energy generation, which constitutes a REC. The systems also track the 

attributes of RECs, such as the type of renewable energy facility (e.g., wind or biomass), 

the project location, and the generation date. 

In compliance markets, tracking systems are used by obligated utilities and by public 

utility commissions (PUCs) that oversee compliance. Utilities use the systems to manage 

all or portions of their REC portfolios, transfer RECs to others, and ultimately to 

demonstrate compliance with the RPS by transferring RECs into retirement accounts. 

RECs deposited into retirement accounts can no longer be traded. PUCs use retirement 

accounts to verify the number of RECs a utility is using to comply with RPS 

requirements. Tracking systems are also used in voluntary markets, though their use is 

not as predominant as in compliance markets. The Green-e Energy certification program, 

a leading certifier and auditor of RECs in the voluntary market, allows green power 

suppliers to use tracking systems to simplify some parts of the Green-e audit process. In 

2012, more than half of Green-e Energy sales used a REC tracking system (Terada 2013). 

In the United States, there are currently nine different tracking systems. REC tracking 

systems in some cases follow the same boundaries as local regional transmission 

organizations or independent system operators (Figure 12). 
26 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 12. Renewable energy tracking systems in North America

The North American Renewables Registry (NAR)

25 covers states and provinces not 

covered by an APX, Inc. tracking system.

Source: Updated from ETNNA 2011

The ability of tracking systems to transfer RECs in and out of their system (exporting or 

importing of RECs) has increased over the past few years (see Table 7). Transfer 

capability is important because some states allow RECs from other states to be used to 

meet state RPS targets. For example, in North Carolina, 25% of compliance can be met 

with out-of-state RECs (i.e., anywhere in the United States). REC import/export 

capability may also be important for the voluntary market. This additional functionality 

has been improved through bi-lateral agreements between tracking systems and in part 

due to the fact that one service provider, APX, Inc., developed most of the regional REC 

tracking systems. 

 

25 For more information, see the “Registries” Web page at http://narecs.com/resources/registries.htm

(accessed September 18, 2013). 
27 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table 7. Export/Import Capability of REC Tracking Systems

Exporting From Exporting To

NAR NC-RETSa

NC-RETS NAR

NAR MIRECS

MIRECS NAR

M-RETSb NAR

M-RETS NC-RETS

M-RETS MIRECS

PJM-GATSc MIRECS

WREGISd NAR

WREGIS NC-RETS

ERCOT NC-RETS

Source: NAR 2013 a North Carolina Renewable Energy Tracking System b Midwest Renewable Energy Tracking System

c PJM-Generation Attribute Tracking System d Western Renewable Energy Generation Information System

Tracking systems can be important providers of public market information. They can 

provide information on the number of RECs retired in a given year. The Texas PUC has 

encouraged public access to REC market data by requiring ERCOT to report annually the 

aggregate quantity of RECs retired for voluntary and compliance purposes. In the current 

reporting year, confidentiality is ensured to account holders, which may be retiring 

compliance or voluntary RECs, but after one year, confidentiality is expired, and ERCOT 

documents how many RECs were retired by each account holder.26 

PJM-EIS has developed a public report on voluntary retirements, and other tracking 

systems are publishing the retirements of Green-e Energy eligible (not necessarily 

retired) RECs. 27 It should be noted that data presented here only represent that a Green-e 

Energy eligible REC was retired; Green-e Energy eligible RECs may also be eligible to 

be retired to meet RPS compliance and ultimately retired for that purpose. Data from 

these sources show that retirements declined in 2012, primarily due to decreases in 

ERCOT and WREGIS (Figure 13). 

 

26 ERCOT’s Annual Report on the Texas Renewable Energy Credit Trading Program can be found at 

www.texasrenewables.com/reports.asp. 27 PJM-GATS public reports can be found at pjm-eis.com/reports-and-news/public-reports.aspx. In addition 

to voluntary retirements, PJM-EIS provides publicly available data on the RECs retired to meet RPS 

compliance in PJM states.
28 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 13. Green-e eligible retirements in tracking systems

In WREGIS, the increase in voluntary eligible retirements in 2011 and a subsequent 

decline in 2012 may have been due to utilities in Washington State increasing their 

compliance retirements; if generators were no longer going to be selling into the 

voluntary market, they may not have continued their Green-e registration, making the 

RECs generated from their projects no longer Green-e eligible (Coon 2013). 

According to ERCOT, the decline in voluntary retirements in 2012 in ERCOT was due to 

increased compliance retirements.28 The compliance retirement increased from 4,264 

MW to 5,256 MW. The MW requirements are then translated to MWh targets through the 

use of a capacity conversion factor (32.2% in 2012). Thus, compliance REC retirements 

increased from about 9 million MWh to about 12 million MWh (Figure 14). Voluntary 

retirements fell from more than 15 million MWh to less than 10 million MWh, not 

including retirements from previous years. 

 

28 For more information, see “Renewable Energy Generation in Texas Continues to Grow, up 7 Percent 

from 2011” at http://www.ercot.com/news/press_releases/show/26445 (accessed October 11, 2013).

 -

 5

 10

 15

 20

 25

 30

 35

2007 2008 2009 2010 2011 2012

Millions of MWh

PJM-EIS

NC-RETS

NEPOOL

M-RETS

WREGIS

ERCOT
29 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 14. Compliance and voluntary retirements in ERCOT, 2007–2013

0

5

10

15

20

25

2007 2008 2009 2010 2011 2012

Millions of MWh Annually

ERCOT Voluntary Retirements

from Previous Years

ERCOT Voluntary Retirements

from Current Year

ERCOT RPS Retirements
30 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

4 REC Pricing in Voluntary and Compliance 

Markets 

Pricing for voluntary RECs differs from compliance REC pricing and from pricing 

offered by utility green pricing programs. Unlike compliance RECs, which generally 

must be sourced from within some geographic region to be eligible for RPS compliance, 

voluntary RECs can be sourced either regionally or nationally. 

This overview of wholesale REC prices presented in this section is based on indicative 

data available from brokers and third-party data providers. With a few exceptions, there 

is little price transparency in REC markets. Most transactions are conducted as bilateral 

contracts between parties, and prices are not reported. In addition, prices can vary widely 

by region. Therefore, data presented here are only indicative and should be used 

with caution. 

In general, REC values depend on several factors, including the technology, the vintage 

(year in which it was generated), the volume purchased, program eligibility (e.g. Green-e 

Energy), the region in which the generator is located, and the market supply/demand 

balance. Natural gas prices can also affect the cost competitiveness of renewable energy 

generation, which is reflected in REC prices. 

Figure 15. Voluntary REC prices, January 2008–July 2013

Source: Marex Spectron 2013 

$0

$1

$2

$3

$4

$5

$6

$7

$8

$9

Voluntary REC Price ($/MWh)

West Wind

National Wind

National Any

Technology
31 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

As shown in Figure 15, wholesale RECs used in voluntary markets have traded at less 

than $2/MWh since 2009. In July 2013, voluntary nationally sourced RECs increased 

above the $1/MWh level for first time since mid-2010. Nationally sourced voluntary 

wind REC prices have been comparable to nationally sourced voluntary RECs for any 

technology, while wind from the western United States has earned higher prices, 

particularly in the 2009–2012 timeframe. 

REC Pricing in Compliance Markets

In the second half of 2011, REC prices began to increase in the Northeast, and through 

early 2013 stabilized at near alternative compliance payment (ACP) levels in 

Connecticut, Massachusetts, New Hampshire, and Rhode Island, while declining to 

around $20/MWh in Maine (Figure 16). ACP levels in the region are generally between 

$55/MWh and $65/MWh, meaning that if REC prices were to increase above that level, 

compliance entities would likely pay the ACP instead of buying RECs. 

In other regions, RECs traded at less than $5/MWh in 2012, though some markets began 

to increase in 2013. REC trades in the mid-Atlantic were closing above $10/MWh in July 

2013 in Delaware, Maryland, New Jersey, and Pennsylvania. In Texas, REC prices have 

doubled from early 2011 through July 2013, but remain at around $2/MWh (Figure 16). 
32 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 16. Compliance market (Tier 1) REC prices, January 2008–July 2013

Plotted values are the last trade (if available) or the mid-point of bid and offer prices for 

the current or nearest compliance year for various state compliance RECs.

Source: Marex Spectron 2013

$0

$10

$20

$30

$40

$50

$60

$70

Compliance REC Price in Northeast 

States ($/MWh)

CT

MA

ME

NH

RI

$0

$5

$10

$15

$20

$25

Compliance REC Price ($/MWh)

DC

DE

IL Wind

MD

NJ

PA

TX
33 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Solar renewable energy certificates have higher values than RECs from other resource 

types in compliance markets. This is true for several reasons. First, 16 states and 

Washington, D.C., have specific provisions to encourage solar or customer-sited 

generation (DSIRE 2011), which creates a different supply and demand dynamic than for 

REC markets. Second, the alternative compliance payment level is often set higher for 

solar/distributed generation tiers than for standard RPS compliance because of the higher 

cost of solar relative to other renewables that may be used to meet the main RPS targets. 

For example, solar alternative compliance payments generally range from about $350 to 

$650/MWh compared to about $55/MWh for the main RPS (Tier 1). 

Spot pricing for solar renewable energy certificate (SRECs) is publically available via

platforms like SRECTrade and FlettExchange.29 SRECTrade hosts a monthly auction, 

while Flett Exchange is an online exchange. Both platforms cover markets in PJM states, 

Massachusetts, and Ohio, and similar price trends can be seen in reported data from both 

companies. Figure 17 shows SREC prices for the current or nearest compliance year. 

Figure 17. Compliance market SREC spot prices, August 2009–August 2013

Source: SRECTrade

For more information, see “SREC Market Prices” at http://srectrade.com/srec_prices.php 

(accessed September 18, 2013) 

In New Jersey, spot market prices for SRECs have been in the $50–$150 range in recent 

years, after declining dramatically from highs of more than $600/MWh into mid-2011. In 

Pennsylvania, a similar, though not as dramatic, decline was seen in mid-2011. Spot 

prices for Pennsylvania SRECs dropped to less than $50/MWh in mid-2011, from around 

$300/MWh in mid-2010 (Figure 17), presumably due to oversupply in the market. By 

2012, Pennsylvania SRECs were down to $50, and have declined to less than $15 in

mid-2013. 

 

29 For more information, see www.srectrade.com and www.flettexchange.com. 

 $-

 $100

 $200

 $300

 $400

 $500

 $600

 $700

Aug-09

Dec-09

Apr-10

Aug-10

Dec-10

Apr-11

Aug-11

Dec-11

Apr-12

Aug-12

Dec-12

Apr-13

Aug-13

Auction Price per SREC

NJ

PA

MD

DC

DE

MA

OH In-state

OH Out-State
34 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

In Washington, D.C., SREC spot prices have increased in recent years, due to policy 

modifications. In 2011, the Council of the District of Columbia closed the door to new 

out-of-district resources ( out-of-district systems approved before January 31, 2011 were 

grandfathered in) and increased the ultimate solar requirement from 0.4% to 2.5% by 

2023. In 2012, SREC prices ranged from $270 to $310, increasing in 2013 to nearly 

$490. 

SREC pricing data are also available from PJM-GATS.

30 PJM-GATS reports solar 

weighted average prices for transactions in the PJM market that differ from spot prices 

reported by SRECTrade and Flett Exchange because PJM-GATS pricing can include 

pricing from long- or mid-term contracts as well as spot prices. PJM-GATS reports prices 

on a monthly basis, based on when the SREC was issued, traded, or retired, not on when 

the generation occurred. For example, if a company contracted for SRECs that were 

generated in January 2013 at a given price but did not retire those SRECs until August of 

2013, the January 2013 price would be reflected in PJM-GATS’s August 2013 solar 

weighted average price report.

 

30 For pricing data and other public reports, see http://pjm-eis.com/reports-and-news/public-reports.aspx. 
35 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

5 Community and Crowdfunded Solar

Increasingly, utilities and third parties are developing community solar programs that 

allow customers to purchase a share of a renewable system developed in the local 

community. Under community solar programs, customers receive the benefits of the 

energy that is produced by their share. For example, the Holy Cross Energy solar project 

in El Jebel, Colorado, is an 80kW photovoltaic system supported by 18 community 

participants who purchase shares at an upfront cost of $3.15/W ($3,150/kW) and then 

receive a credit on their bill each month at a rate of $0.11/kWh (see Footnote 20). 

Typically, community solar programs require an upfront investment in a “share” or 

“panel” of the project, which can cost hundreds of dollars. However, that is not always 

the case. Delta-Montrose Electric Association’s Community Solar Array program, also in 

Colorado, sells shares in $10 increments.31

Unlike green pricing programs or unbundled REC purchases, the RECs produced by a 

community solar program are typically, though not always, retained by the host utility. 

The utility may use the RECs to comply with a renewable portfolio standard or to meet a 

voluntary renewable energy target. Without REC ownership, consumers cannot claim the 

environmental benefits of the solar project.

However, community solar programs provide choice to consumers, and they provide 

potential cost savings on electricity bills. Consumers participating in community solar 

programs may also pay less per watt compared to an on-site installation if they installed 

solar on their roofs, due to economies of scale. Community solar programs typically also 

allow consumers to keep their shares if they move within the utility’s service territory. 

For more on these issues, see Heeter and McLaren (2012).

Due to these advantages and other reasons, the community solar market is growing. In 

2012, 10 programs were introduced, and as of July 2013, 6 programs had begun in 2013, 

with 9 projects under development. U.S. community solar programs had a combined 

capacity of more than 14,066 kW as of June 2013, and that capacity has been growing 

(Figure 18). In 2011, the Salt River Project (Arizona) began a 2,000-kW program for 

residential participants. Two additional large (greater than 1,000 kW) programs were 

developed in Arizona: Tucson Electric Power’s 1,600-kW program in 2011 and 

UniSource Energy Service’s 1,720-kW program in 2012. San Miguel Power Association, 

working with the Clean Energy Collective (Colorado) also developed a large system 

(1,000 kW) in 2012. 

 

31 For more information, see “Delta-Montrose Electric Association (Colo.) Launches Community Solar” at 

http://apps3.eere.energy.gov/greenpower/news/news_template.shtml?id=1620 (accessed October 3, 2011). 
36 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Figure 18. Community solar program cumulative capacity (kW)

In Colorado, legislation was passed in June 2010 requiring that investor-owned utilities

develop plans to acquire RECs from community solar gardens. The bill required the PUC 

to set a minimum and a maximum purchase of electrical output for each utility. To 

comply, the state’s largest utility, Xcel Energy, offers an incentive under the 

Solar*Rewards Community program. During 2012 Xcel Energy accepted 4.5 MW of 

customer owned community solar electricity; it will pay $0.14 per kWh for small 

programs (10–50 kW), and $0.11 per kWh for medium programs (50–500 kW), then 

scale down the payments over time after 3 MW of capacity has been installed. An 

additional 4.5 MW was made available to community solar developers on August 15, 

2012, and Xcel closed the application process after 30 minutes, as three times the 2012 

capacity allotment had been submitted; 10 solar garden applications were approved, 

ranging from 108 kW to 1,997 kW. In 2013, Xcel added 4.5 MW of projects under its 

Standard Offer Program (for systems between 10 kW and 500 kW), and began accepting

bids for its Large RFP Program (for systems between 500.1 kW and 2 MW) on August 1, 

2013. The Large RFP Program will accept up to 4.5 MW as well, for a total of 9 MW 

added to the Solar*Rewards Community program this year. 

Outside of Colorado, other states have also passed legislation, either requirements or 

incentives, to support community solar. In May 2009, the state of Washington passed SB 

6170, which enables community solar participants to qualify for the state’s production 

incentive program (DSIRE 2012). Projects up to 75 kW are eligible. The production 

incentive can range between $0.12/kWh and $0.54/kWh, depending on whether the 

project qualifies for certain local content multipliers, and each participant in a community 

solar project is eligible to receive the incentive, which is capped at $5,000 per year per 

participant (DSIRE 2012).

In Maine, net metering regulations allow for shared ownership of facilities up to 660 kW 

located in the service territory of an investor-owned transmission and distribution utility. 

(CMR 65-407-313) also allows group net metering. 

0

5,000

10,000

15,000

20,000

25,000

Cumulative Capacity (kW)
37 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

In Vermont, the Public Service Commission approved group billing, which allows for net 

metering to be shared among multiple customers. Group billing can be applied to 

technologies other than solar, including wind, small hydro, and biomethane. (Vermont 

PSC 2009) 

In 2013, Minnesota passed a law requiring Xcel Energy to set up and operate a 

community solar gardens program. Other investor-owned utilities in Minnesota are not 

required to, but may, offer community solar. 

In California, a community solar bill (SB 43) was signed into law in September 2013. 

The bill creates a community solar pilot program for California’s three investor-owned 

utilities (PG&E, SCE, and SDG&E), with a cap of 600 MW. PG&E expects that its 

current proposal for a green pricing program would be similar to that required by SB 43 

(Hoyt 2013). 

In Washington, D.C., the Community Renewables Energy Act of 2013 (Bill No. 20-

0057) was approved by the City Council in October 2013. The Act enables community 

solar and other aggregated net metering arrangements. Projects can be up to 3 MW in size 

and must have at least two subscribers. 

5.1 Intersection of On-Site Solar and Green Pricing Programs

Utilities offering green pricing programs may also be providing customers with 

opportunities to install on-site solar or participate in a community solar garden. Given 

these potentially competing programs, how are utilities handling the potential overlap? 

This section provides lessons learned from top green power programs after a series of 

interviews (see Section 7 for details on the interview process and other lessons learned). 

Green pricing managers anecdotally think there is overlap between customers who 

participate in green pricing and other offers, but data supporting this assumption are hard 

to find; data may not be readily available because programs are often run by different 

department within the utility, and some programs may be run by third parties. Xcel 

Energy has found that it is losing about 2,000 MWh annually from its Windsource 

program in Colorado due to net metering customers either leaving Windsource entirely or 

decreasing the size of their Windsource purchase (Mudd 2013). 

A few utilities mentioned that their customers with on-site solar are signing up for the 

green pricing program to match the electricity not covered by their photovoltaic (PV) 

system. 

One reason that utilities may not see a large impact of customers choosing on-site solar 

on their green pricing program is that for most leading utilities, the number of customers 

installing on-site solar is far fewer than the number of green pricing customers. In fact, 

the top three utilities in terms of PV net metering customers (listed in EIA) do not even 

have a green pricing program, though PG&E is seeking approval of a green pricing 

program (Tables 8 and 9). The number of PV net metering customers is used here as a 

proxy for the number of PV systems installed. 
38 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table 8. Utilities Reporting to EIA with Most PV Net Metering Customers, 2011

Utility or Electric Supplier State Total PV Net Metering Customers

Pacific Gas & Electric CA 59,597

Southern California Edison CA 28,058

San Diego Gas & Electric CA 14,941

Public Service Company of Colorado CO 9,633

Jersey Central Power & Light NJ 5,779

Hawaiian Electric Company HI 5,556

Long Island Power Authority NY 4,807

Public Service Electric & Gas NJ 4,725

Los Angeles Department of Water and Power CA 4,672

Arizona Public Service Co. AZ 3,814

Source: EIA 861

Table 9. Net Metering Customers at Utilities Reporting to EIA with Most Green 

Power Customers, 2011

Utility or Electric Supplier State Total Green 

Power Customers

Total PV Net 

Metering 

Customersa

Green Mountain Energy Company TX 296,101 n/a

Portland General Electric Co OR 79,776 2,112

Just Energy TX 54,232 n/a

Sacramento Municipal Utility District CA 51,509 3,180

First Choice Power TX 42,555 n/a

PacifiCorp OR 39,446 1,981

Public Service Co. of Colorado CO 33,774 9,633

PacifiCorp UT 32,550 1,057

Puget Sound Energy Inc. WA 32,459 1,010

Just Energy New York Corp. NY 31,640 n/a

PECO Energy Co. PA 24,629 1,956

Detroit Edison Co. MI 22,689 591

Wisconsin Electric Power Co. WI 20,927 239

Northern States Power Co - Minnesota MN 20,347 305

Source: EIA 861

a

 Net metering only applies to regulated distribution companies. 

Some programs do not see overlap in customers because of the way they are structured. 

For example, Indianapolis Power & Light offers a feed-in tariff, but that program is 

dominated by large renewable energy developers. However, they recently offered an 
39 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

electric tariff for electric vehicles and have had some inquires about whether electric 

vehicle meters can be enrolled in the green pricing program. 

5.2 Crowdfunding Solar 

“Crowdfunding” is used to finance many types of projects, not just renewable energy. 

Kiva and Kickstarter, for example, are two platforms through which individuals can 

support a wide variety of crowd-funded projects. Crowdfunding renewable projects 

differs slightly from community solar in that crowdfunding participants provide upfront 

capital (as a loan) to support the development of the project rather than purchase shares 

of the project. Crowd-funded programs allow anyone, regardless of utility territory, to 

invest in the development of a renewable project. 

Mosaic32 is a crowdfunding program based in California, specifically for solar 

development. Crowdfunding program give anyone (regardless of utility territory) the 

opportunity to invest in the development of a solar facility, which is typically hosted by a 

non-profit organization, though access may be restricted to certain states or accredited 

investors. To date, Mosaic has financed 15 solar facilities totaling more than 3 MW. The 

majority of projects (nine) are located in California; other projects are located in Arizona, 

New Jersey, and Colorado. The first five projects were funded by more than 400 people 

for a total of more than $350,000 in zero-interest loans. Mosaic now offers projects with 

an annual return ranging from 4.5% to 5.4%. 

The JOBS Act, signed in April 2012 by President Obama, grants crowd-funded projects 

raising up to $1 million annually an exemption from the U.S. Securities and Exchange 

Commission’s securities regulation, allowing them to provide a return on investment, 

provided they file initial and periodic disclosures to the SEC. The SEC is now developing 

the regulations required to implement the JOBS Act.

 

32 For more information, see joinmosaic.com. 
40 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

6 Interest of Large Consumers in New Voluntary 

Options

The number of companies involved with green power is increasing, and the range of 

methods they use to procure renewables is expanding. Large consumers are interested in 

individual tariffs for renewable energy in their service territories, entering into power 

purchase agreements directly, or buying RECs. 

Large customers are sometimes excluded from utility green pricing programs, but some 

large customers are interested in purchasing renewables from projects located in their 

service territory. An emerging voluntary purchase option is targeted at large commercial 

or industrial customers. Three utilities are in the initial stages of developing this type of 

tariff. 

In April 2013, Google announced its support for an approach that would allow them to 

subscribe to a separate tariff for renewable energy. Google’s proposed “renewable energy 

tariff” would be a voluntary tariff that would pass the cost of the renewable power 

directly to the consumers who want it.33 This type of arrangement would allow Google to 

focus on its core business, instead of developing expertise in power purchase agreements 

or other contract mechanisms. Duke Energy is expected to file a similar plan in 2013.34 

Sierra Pacific Power Company (SPPC) proposed a tariff designed to allow large 

customers to enter into a contract with them to procure renewable energy from a specific 

source.35 The Commission ruled in Docket 12-11023 that the merits of any tariff should 

be addressed once a specific contract is presented to the Commission for approval. 

Apple is partnering with SPPC through the new tariff, working with SunPower for 

engineering and construction of an 18-MW to 20-MW solar farm near its data center in 

Reno, Nevada.36

Dominion Virginia Power has proposed a renewable generation pilot program (“RG Pilot 

Program” or Rate Schedule RG – Renewable Energy Supply Service).37 The program 

would allow large customers to purchase renewable energy from renewable facilities 

located within PJM, at a negotiated term length. The proposed pilot is capped at 

240,000,000 kWh or 100 customers. Participants would reduce their energy billing but 

 

33 For more information, see “Expanding Renewable Energy Options for Companies Through UtilityOffered ‘Renewable Energy Tariffs’ at http://static.googleusercontent.com/external_content/

untrusted_dlcp/www.google.com/en/us/green/pdf/renewable-energy-options.pdf (accessed October 14, 

2013). 34 For more information, see “Expanding Options for Companies to Buy Renewable Energy” at 

http://googleblog.blogspot.com/2013/04/expanding-options-for-companies-to-buy.html (accessed October 

14, 2013). 35 Sierra Pacific Power Company also proposed a traditional green power tariff, which allows customers to 

purchase either 50% or 100% renewable energy. That tariff was approved. 

36 For more information, see “Apple is Planning a Solar Panel Farm for its Data Center in Reno” at 

http://gigaom.com/2013/07/01/apple-is-planning-a-solar-panel-farm-for-its-data-center-in-reno/ (accessed 

September 26, 2013). 37 Case No. PUE-2012-00142
41 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

continue to pay demand charges on 100% of their demand. Customers would not pay fuel 

rider costs on the renewable portion. The Virginia State Corporation Commission has not 

yet ruled on the matter.

As large customer utility green tariffs are emerging as an option, the number of 

organizations obtaining renewables through power purchase agreements is increasing. 

Figure 19 shows non-utility off-takers of wind, ranging from corporations such as 

Walmart to universities such as Ohio State. 

Figure 19. Non-utility off-takers of wind

Source: Di Capua (2013) 
42 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

These and other purchasing options are recognized by the EPA’s Green Power 

Partnership. Although the Partnership is not new, it continues to recognize efforts of large 

purchasers, and has continued to grow over time. The number of organizations in 

Partnership has increased over time (Figure 20). As of July 2013, there were 1,512 

Partners, an increase of 10% since the end of 2012. The level of green power sales 

supported by Partners increased 13% from 2011 to 2012, and it was up 18% in July 2013 

compared to year-end 2012. Partners are primarily purchasing unbundled RECs (75%). 

Figure 20. Growth in the EPA Green Power Partnership, 2006–July 2013

 -

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2006 2007 2008 2009 2010 2011 2012 2013

(July)

Number of Green Power Partners

Annual Generation by Category

(Millions of MWh)

Onsite

Competitive Markets

Utility Green Pricing

Unknown

Unbundled REC Markets

Number of Partners
43 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

7 Lessons from Large Green Pricing Programs 

In 2012, NREL reached out to 15 utilities with green pricing programs deemed leading 

programs both in terms of green power sales (according EIA data38) and in terms of data 

previously collected by NREL. We interviewed or gathered detailed responses by email 

from 11 of the 15 utilities. Utilities were asked about a variety of topics. This section 

summarizes their responses and additional information obtained from publically available 

resources. The experiences highlighted here are not intended to provide a representative 

sample of the utility green pricing market. 

7.1 Product History

Energy Mix

Nearly all of the programs included in the interviews were providing green products that 

were mostly supplied by wind. This is consistent with national green pricing trends, 

where wind has historically provided 75%–85% of green pricing supply. One product has 

historically been approximately 40% landfill gas and continues to be so. Most programs 

reported having not significantly changed their energy mixes over time, though one 

program has moved to a higher percentage of wind; originally it consisted of 

approximately one-third wind and it is consists of more than 95% wind. A few programs 

have added more solar over time, primarily from local facilities, though the total 

percentage supplied by solar in those programs remains small (less than 5%). One utility 

has continued to add more dairy digester projects in recent years, citing the popularity of 

the program.

Competition from REC Marketers

Utility green pricing programs with prices higher than unbundled RECs may see 

challenges retaining large, nonresidential customers. The vast majority of utility green 

pricing programs interviewed noticed the appearance of unbundled RECs around 2009, 

though one program noted a shift in 2002–2003. Green pricing managers noted that some 

large nonresidential customers had dropped their program in favor of lower-priced 

products. One green pricing manager noted that his utility used to be invited to 

conversations with large companies about their renewable procurement, but that has since 

waned. 

To retain or continue to attract large nonresidential green pricing customers, some 

utilities emphasize the local nature of their product and the marketing benefit of 

partnering with the utility (when the utility has a good reputation). One program manager 

indicated that if his product were only twice as much as unbundled RECs, he could 

possible make a compelling case to a large nonresidential customer, but when his 

products was 10 times more expensive, this was not possible. Another program indicated 

that it had revised procedures to allow for greater use of their product to get LEED 

(Leadership in Energy and Environmental Design) points, though only a few customers 

used the new procedure. 

 

38 EIA’s Annual Electric Power Industry Report collects data on utility green pricing programs. See 

www.eia.gov/electricity/data/eia861/. 
44 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

One utility program that offered a low price, comparable to unbundled RECs, indicated 

that it had not seen a shift in nonresidential participation. 

7.2 Pricing

Pricing Methodology

Top green pricing programs interviewed use different methodologies to set the price of 

their products. Some of this variation is due to how the product supply is procured. In 

nearly all cases, utilities were either prevented from earning a profit on their green 

product by their regulator or chose not to profit from the program for other reasons. One 

exception is a program that indicated it tries to be slightly revenue positive, in case 

revenue fluctuates from year to year. Another program indicated that if net revenues are 

positive, it will invest the revenue in more RECs and local solar projects. The primary 

methods for setting the price are: 

• REC cost. The majority of programs interviewed determined the price by adding 

the cost of the renewable supply to any marketing and administrative expenses. In 

some cases, determining the renewable supply costs is relatively easy (e.g., if the 

cost is from purchasing unbundled RECs). 

• Incremental cost of renewable energy. In markets where renewable energy is 

being procured in a bundled manner, the cost of the renewable supply can be 

determined by subtracting the average cost of procuring non-renewables to the 

average cost of procuring renewables. In its recent rate case, WE Energies set the 

price of its green pricing product by comparing the average cost of procuring 

renewables to the average cost of procuring non-renewables, and then added 

marketing and administrative expenses. The cost for renewables was determined 

to be $0.10186/kWh, compared to the non-renewable cost of $0.07971/kWh, 

leaving a renewable premium of $0.02401. WE Energies added administrative 

costs of $0.00185/kWh for the “mass market” program and $0.0005/kWh for the 

“bulk market” program.39 Madison Gas and Electric uses a similar approach.40 

• Based on proposals. Some programs are not administered directly by utilities. In 

those cases, the green power price is typically established through a bidding 

process. For example, in Connecticut, energy suppliers bid on the opportunity to 

supply the CTCleanEnergyOptions program. Energy suppliers bid an “all-in” 

price that includes supply, administration, and marketing expenses. 

 

39 See Docket 5-UR-106, Exhibit-WEPCO/WG-Rogers-10, Schedule 6. 40 For more information, see “Green Power Tomorrow—Frequently Asked Questions” at 

http://www.mge.com/Images/PDF/CleanPower/GS1381_GPTFreqAskedQuestions.pdf (accessed October 

14, 2013. 
45 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Administrative Expenses

Programs may be criticized for spending what can be perceived as a large amount of the 

price on marketing and administration; however, most programs recognized that 

marketing expenses are essential to getting new customers to participate, although data is 

sensitive. Marketing and administrative expenses can also be challenging to compare 

across utility programs, as utilities may classify expenses differently. 

For the utilities willing to discuss administrative expenses, a wide range of expenses was 

reported. Two programs reported expenses less than 1% of the total cost to the product. 

One program reported around one-sixth of the gross revenue for the product, while 

another reported about 50% of the total cost of the product. 

7.3 Customers

Customer Segmentation and Research

Utilities regularly engage in customer segmentation and research, though none wanted to 

share that research publically. Most programs interviewed reported conducting research 

every few years and before introducing a new or modified product or marketing 

campaign. Some utilities conduct research on their green pricing program as part of larger 

effort to survey customer satisfaction. Examples of customer segmentation and research 

include: 

• One utility that already procures a large amount of non-fossil fuel conducted 

research to determine important program goals and relevant marketing messages 

for their green product. 

• Another utility includes its green pricing program in its regular customer 

perception studies, and it tracks results quarterly.

• Utility programs run in part or whole by third-party suppliers often rely on those 

suppliers to conduct customer segmentation and research. 

• One program reported not conducting extensive market research, but it did track 

its large commercial and industrial customers that have national or international 

operations with some kind of environmental or sustainability policy. 

Customer Recognition

Nearly all programs interviewed currently or historically have provided some form of 

customer recognition for their large purchasers. Customer recognition most commonly 

takes the form of a listing on a website, but some programs recognize large purchasers in 

a newspaper or other publication. A few considerations for publicizing large purchasers

include: 

• Making sure the customer approves of being publically recognized 

• Ensuring that the customer name published is one that is recognizable, not 

necessarily using the name on the electric account
46 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Success Factors 

Overall, program managers cited several broader reasons for the success of their green 

pricing programs, including: 

• Providing an open, transparent, personable, highly visible program 

• Having the support of the management team 

• Working with an experienced, third-party contractor

• Engaging the community, particularly through community challenges 

• Focusing on including local, independent renewable projects in the green pricing 

supply mix 

• Providing an advertising benefit to large customers 

• Being responsive to market needs (e.g., changing a residential offer to something 

that can be easily understood). 

Future Program Changes

Moving forward, utility green pricing programs face challenges, particularly because 

their green pricing offers are usually more expensive than unbundled RECs. To address 

this and other issues, several utilities indicated they are planning to modify their green 

pricing programs: 

• One utility is pursuing a new lower price for bulk purchases, and it has hired a 

third-party marketing firm to investigate this option. 

• Another utility recently increased its price and will be examining the impact on 

customer participation. This utility uses some of its own generation to supply the 

green pricing program, so if sales decrease substantially, it will investigate how to 

make up the lost revenues. 

• Three utilities are planning to revisit their marketing approach.

• One utility program is considering a major revision to its program. The proposal 

would offer a 3–5 year portfolio-based product at a fixed price. The utility did not 

want to make public the details of the program at this time.

• One utility is looking to introduce a community solar option, similar to the 

Sacramento Municipal Utility District’s program except that it would involve 

selling the RECs from the community solar array to customers. The utility is 

hoping to launch this option in 2014. 
47 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

8 Conclusions and Observations

Voluntary green power markets provide a way for individuals and institutions to support 

renewable energy. Emerging methods for support include community solar programs, 

crowdsourced solar, power-purchase agreements. Based on these emerging methods as 

well as data from green power programs, competitive markets, and unbundled REC 

purchases, we have identified the following market trends: 

• In 2012, total retail sales of renewable energy in voluntary purchase markets 

exceeded 48 million MWh and represented approximately 1.3% of total U.S. 

electricity sales. The figures represent a capacity equivalent of approximately 

17,000 MW. Total green power market sales increased by 36% from 2010 to 

2012, which translates to a compound annual growth rate of 17%. 

• Wind energy continues to provide the most renewable energy to voluntary 

markets, at 80.1% of total green power sales, followed by landfill gas and biomass 

(12.8%), hydropower (6.2%), solar (0.6%), and geothermal (0.3%). The 

percentage of solar used in the voluntary market increased from 0.2% to 0.6% and 

represents about 2% of sales in utility green pricing programs. 

• Utility green pricing sales exhibited growth of 5% in 2012, which is similar to the 

growth seen in 2010 and 2009. 

• Utilities and third parties are developing community solar programs. These 

programs enable utility customers to purchase a share of a system and receive the 

benefits of the energy produced by their share. In 2012, 10 new community solar 

projects were introduced, and as of July 2013, an additional 6 programs had 

begun. The capacity of existing community solar projects totals more than 14 

MW, and an additional 13 MW of projects are under development. 

• Competitive markets saw slower growth than in previous years, increasing at a 

compound annual growth rate of 6% from 2010 to 2012. Some of the downturn 

may be due to declining voluntary sales in Texas. 

• REC markets were the fastest growing and largest market segment, increasing at a 

compound annual growth rate of 25% from 2010 to 2012. The REC market 

appears to have rebounded from 2010, when it only grew 6% compared to 2009. 

• Nearly 1.9 million customers purchased green power in 2012. The number of 

customers purchasing unbundled RECs nearly doubled in 2012, driven primarily 

by residential customers. 

• Wholesale RECs used in voluntary markets declined from around $5/MWh in 

2009 to less than $1/MWh in 2010 through mid-2013. In July 2013, nationally 

sourced voluntary RECs increased to more than $1/MWh, as the market in Texas 

began to tighten. 
48 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

References

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Laboratory. 

Bird, L.; Kreycik, C.; Friedman, B. (2008). Green Power Marketing in the United States: 

A Status Report (Eleventh Edition). NREL/TP-6A2-44094. Golden, CO: National 

Renewable Energy Laboratory. Accessed September 2010: http://www.nrel.gov/ 

docs/fy09osti/44094.pdf. 

Bird, L.; C. Kreycik; Friedman, B. (2009). Green Power Marketing in the United States: 

A Status Report (2008 Data). NREL/TP-6A2-46581. Golden, CO: National Renewable 

Energy Laboratory. Accessed October 4, 2011: http://www.nrel.gov/docs/fy09osti/ 

46581.pdf. 

Bird, L.; Sumner, J. (2010). Green Power Marketing in the United States: A Status 

Report (2009 Data). NREL/TP-6A20-4940. Golden, CO: National Renewable Energy 

Laboratory. Accessed September 2011: http://www.nrel.gov/docs/fy11osti/49403.pdf. 

“Database of State Incentives for Renewables & Efficiency (DSIRE).” (2013). North 

Carolina State University. Accessed September 19, 2013: http://www.dsireusa.org/. 

Di Capua, M. (May 23 2013). Email. New York, NY: Bloomberg New Energy Finance. 

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by Provider.” Accessed September 13, 2013: http://www.eia.gov/electricity/annual/html/

epa_02_02.html. 

Environmental Protection Agency (EPA). (July 11, 2013). Green power partners and 

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EPA. (2013). “National Top 50.” Green Power Partnership. Accessed September 18, 

2013: http://www.epa.gov/greenpower/toplists/top50.htm. 

Environmental Tracking Network of North America (ETNNA). (2011). “Renewable 

Energy Tracking Systems.” Accessed September 20, 2011: http://www.etnna.org/ 

learn.html. 

Google. (2013). “Investing in a clean energy future.” http://www.google.com/green/ 

energy/investments/. Accessed October 14, 2013. 

Friedman, B.; Miller, M. (2009). Green Pricing Program Marketing Expenditures: 

Finding the Right Balance. NREL/TP-6A2-46449. Golden, CO: National Renewable 

Energy Laboratory. Accessed October 18, 2013: 

http://www.nrel.gov/docs/fy09osti/46449.pdf
49 

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National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Heeter, J.; Armstrong, P.; Bird, L. (2012). Market Brief: Status of the Voluntary 

Renewable Energy Certificate Market (2011 Data). NREL/TP-6A20-51904. Golden, CO: 

National Renewable Energy Laboratory. Accessed October 9, 2013: 

http://www.nrel.gov/docs/fy12osti/56128.pdf. 

Heeter, J.; McLaren, J. (2012). "Innovations in Voluntary Renewable Energy 

Procurement: Methods for Expanding Access and Lowering Cost for Communities, 

Governments, and Businesses." NREL/TP-6A20-54991. Golden, CO: National 

Renewable Energy Laboratory. Accessed October 14, 2013: 

http://www.nrel.gov/docs/fy12osti/54991.pdf. 

Heeter, J.; Bird, L. (2011). Status and Trends in U.S. Compliance and Voluntary 

Renewable Energy Certificate Markets (2010 Data). NREL/TP-6A20-52925. Golden, 

CO: National Renewable Energy Laboratory. Accessed October 9, 2013: http://www.

nrel.gov/docs/fy12osti/52925.pdf . 

Hoyt, M. (23 September 2013). “Proposed Enhanced Green Option.” Presentation at the 

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Marex Spectron. (2013). Data accessed through Vantage database. London, UK. 

Accessed September 18, 2013: http://www.marexspectron.com/. 

Mosaic. (2013). “Browse Investments.” https://joinmosaic.com/browse-investments. 

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Mudd, S. (27 September 2013). Email. Xcel Energy, Denver, Colorado. 

Natural Marketing Institute. (2011). Consumer Attitudes About Renewable Energy: 

Trends and Regional Differences. Work performed by the Natural Marketing Institute: 

Harleysville, PA. NREL/SR-6A20-50988. Golden, CO: National Renewable Energy 

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Solar Energy Industries Association (SEIA) and GTM Research. (2013). U.S. Solar 

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Terada, R. (12 September 2013). Email. Center for Resource Solutions, San Francisco, 

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Vermont Public Service Commission (PSC). (2009). Rule 5.100 – Relating to Net 

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5100adoptedrule_2.pdf. Accessed October 14, 2013.
50 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Appendix A. Leading Purchasers in the EPA Green Power Partnership Table 

A-1. Top 25 Purchasers in the EPA Green Power Partnership Program, July 

3, 2013 

Organization Annual Green 

Power Usage 

(kWh)

Providersa Green Power 

Resources

1. Intel Corporation 3,100,850,000 Sterling Planetb, PNM, on-site generation biogas, biomass, 

small-scale 

hydropower, solar, 

wind

2. Microsoft Corporation 1,935,637,485 Sterling Planetb, on-site generation Biomass, small-scale 

hydropower, solar, 

wind

3. Kohl's Department Stores 1,536,529,000 Nexantb

, Sterling Planetb, Renewable Choice Energyb, 

3Degreesb

, on-site generation

solar

4. Whole Foods Market 800,257,623 3Degreesb

, on-site generation solar, wind

5. Walmart Stores, Inc. 751,431,792 Noble Americas Energy Solutions, Duke Energy, on-site 

generation, Green Power EMCb

, Oklahoma Gas & Electric

biogas, solar, wind

6. U.S. Department of Energy 698,489,099 Various, on-site generation biomass, geothermal, 

small-scale 

hydropower, solar, 

wind

7. Staples 635,982,674 Renewable Choice Energyb

, 3Degreesb, Sterling Planetb, 

Avista Utilities, Pacific Powerb

, Tennessee Valley Authorityb, 

on-site generation, Portland General Electric, Florida Power 

& Lightb

biogas, solar, wind

8. City of Houston, TX 622,887,000 Reliant Energyb wind

9. Starbucks Company-Owned Stores 592,462,522 3Degreesb

, Nexantb wind
51 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Organization Annual Green 

Power Usage 

(kWh)

Providersa Green Power 

Resources

10. Apple Inc. 537,393,667 3 Phases Renewablesb, TerraPass / NC GreenPowerb, 

Constellation, on-site generation, Austin Energyb

, 

Sacramento Municipal Utility Districtb

, Iberdrola 

Renewablesb

, Pacific Powerb, NV Energy, Central Electric 

Cooperative, Silicon Valley Powerb

biogas, biomass, 

geothermal, smallscale hydropower, 

solar, wind

11. District of Columbia 534,084,977 Washington Gas Energy Servicesb wind

12. Cisco Systems, Inc. 459,005,742 Sterling Planetb

, NextEra Energy Resourcesb, Austin 

Energyb

, Ameren Missourib, on-site generation

solar, wind

13. Unilever 439,105,000 Renewable Choice Energyb biomass, wind

14. Lockheed Martin Corporation 431,108,840 Sterling Planetb

, 3Degreesb, EDF Industrial Power 

Servicesb

, GDF Suez Energy Resources NAb, Champion 

Energy Servicesb

, Noble Americas Energy Solutionsb, City 

of Palo Alto Utilitiesb

, South Alabama Electric Cooperativeb

biomass, solar, wind

15. U.S. Department of Veterans Affairs 400,000,000 Renewable Choice Energy biogas

16. BD 382,462,000 Renewable Choice Energyb

, 3Degreesb, Rocky Mountain 

Powerb

, Bloom Energyb, on-site generation

solar, wind

17. City of Austin, TX 374,086,079 Austin Energyb wind

18. Hilton Worldwide 315,000,000 Renewable Choice Energyb small-scale 

hydropower, wind

19. McDonald's USA LLC 309,185,000 3Degreesb

, Sterling Planetb wind

20. City of Dallas, TX 282,961,000 TXU Energyb wind

Source: EPA 2013 a

 Listed in descending order by kWh supplied to partner

b

Indicates Provider is selling Partner a third-party certified green power product
52 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Appendix B. Estimated U.S. Green Pricing 

Customers and Sales by State

Figures reported in this appendix do not include all sales and customers from competitive 

retailers, and they therefore underestimate sales and customers in states that allow retail 

competition. 

Table B-1. Estimated U.S. Green Pricing Customers and Programs by State, 2010 and 2011 

State Customers 

(2010)

Customers 

(2011)

Electric Industry

Participants (2011)

AK - - - 

AL 1,679 1,832 27

AR 23 94 7 

AZ 7,839 5,771 4 

CA 82,848 84,520 15

CO 51,677 45,231 29

CT 23,956 26,854 12

DC 2,814 - 5 

DE 2,280 2,923 9 

FL 2,668 2,517 5 

GA 8,032 8,054 24

HI - - 0 

IA 8,391 8,207 19

ID 4,803 4,727 32

IL 5,460 8,269 6 

IN 6,908 6,873 13

KS 174 104 6 

KY 3,641 3,230 26

LA 531 - 2 

MA 15,349 19,736 12 

MD 12,495 16,154 11

ME 2,302 1,302 2 

MI 34,384 37,153 13

MN 33,981 31,476 86

MO 6,823 7,154 18

MS 1,254 174 17

MT 497 831 10

NC 12,915 11,901 32 
53 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

State Customers 

(2010)

Customers 

(2011)

Electric Industry

Participants (2011)

ND 1,526 1,622 7 

NE 160 1 4 

NH 90 480 4 

NJ 1,705 3,807 8 

NM 19,600 16,911 12

NV 26 24 2 

NY 91,532 90,167 17

OH 3,891 1,363 11

OK 16,849 16,872 14

OR 122,671 126,741 27

PA 35,397 37,621 17

RI 4,580 4,458 2 

SC 5,925 7,189 22

SD 514 498 8 

TN 9,502 10,213 72

TX 411,615 465,439 30 

UT 30,060 32,611 9 

VA 12,817 12,800 7 

VT 4,692 4,471 2 

WA 53,074 52,316 25

WI 51,361 49,970 66

WV 310 3 2 

WY 4,961 5,372 8 

Total 1,216,582 1,276,036 819 

Sources: EIA 2011, 2012
54 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table B-2. Estimated U.S. Green Pricing Customers by Customer Class, 2002–2011

Year Electric Industry 

Participants

Participating Customers

Residential Nonresidential Total 

2002 212 688,069 23,481 711,550

2003 308 819,579 57,547 877,126

2004 403 864,794 63,539 928,333

2005 442 871,774 70,998 942,772

2006a 484 606,919 35,937 642,856

2007 591 773,391 62,260 835,651

2008 643 918,284 64,711 982,995

2009 722 1,058,185 65,593 1,123,778

2010 776 1,137,047 79,535 1,216,582

2011 811 1,187,867 91,117 1,278,984

a In 2006, the single largest provider of green pricing services in the country discontinued 

service in two states. More than 297,600 customers in green pricing programs reverted to 

standard service tariffs, predominantly in Ohio and Pennsylvania. 

Nonresidential may include some customers for whom no customer class is specified. 

Sources: EIA 2010, EIA 2011, EIA 2012
55 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table B-3. EIA Estimated U.S. Green Pricing Sales (MWh) by State, 2011

State 2011 Sales

(MWh)

State 2011 Sales

(MWh)

TX 8,305,485 GA 76,246 

OR 1,206,335 MO 75,143 

NY 678,060 IA 65,304 

CA 665,943 SC 64,748 

WA 583,456 NJ 63,101 

IL 459,249 OH 40,416 

WI 451,449 WY 38,937 

OK 441,684 ID 37,914 

CO 353,549 NC 23,685 

CT 292,155 AR 23,069 

PA 269,114 FL 18,461 

MN 253,027 VT 16,595 

MD 196,889 SD 12,126 

IN 188,656 ME 8,181 

MI 182,658 ND 6,469 

AZ 178,798 MT 6,078 

UT 173,925 AL 6,049 

RI 160,558 KS 3,931 

MA 148,128 NH 2,211 

VA 124,702 MS 1,094 

NM 121,757 NE 133 

KY 95,394 NV 71 

TN 80,261 WV 19 

DE 76,300 LA - 

Total 16,277,513

Source: EIA 2012
56 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Appendix C. Top 10 Utility Green Pricing 

Programs

Table C-1. Green Pricing Program Renewable Energy Sales, December 2012 

Rank Utility Sales (MWh/year)

1 Portland General Electric 834,125

2 Austin Energy 744,443

3 PacifiCorp 604,007

4 Sacramento Municipal Utility District 416,477

5 Xcel Energy 390,056

6 Puget Sound Energy 365,796

7 Connecticut Light and Power Co. / United Illuminating 254,838

8 Dominion Virginia Power 250,364

9 Oklahoma Gas & Electric Co. 210,187

10 CPS Energy 179,786

Table C-2. Green Pricing Program Total Number of Customer Participants, December 2012 

Rank Utility Participants

1 Portland General Electric 87,987

2 PacifiCorp - Blue Sky Usage, Block, and Habitat 87,919

3 Xcel Energy 61,315

4 Sacramento Municipal Utility District 55,207

5 Puget Sound Energy 34,962

6 Connecticut Light and Power Co. / United Illuminating 27,664

7 Iberdrola: NYSEG and RG&E 21,201

8 We Energies 20,066

9 National Grid 18,302

10 Dominion Virginia Power 15,179
57 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table C-3. Green Power Sales as a Percentage of Total Retail Electricity Sales (kWh), 

December 2012 

Rank Utility % of Load

1 Waterloo Utilities 23.9%

2 Edmond Electric 10.7%

3a City of Palo Alto 8.1%

3 River Falls Municipal Utilities 7.3%

4 Austin Energy 6.0%

5 Portland General Electric 4.4%

6 Madison Gas & Electric Co. 4.1%

6 PacifiCorp - Blue Sky Usage and Habitat 4.1%

8 Sacramento Municipal Utility District 3.9%

9 Stoughton Utilities 2.9%

10 Silicon Valley Power 2.8%

a City of Palo Alto provided an updated response after the submission deadline. The 

updated ranking is provided here but the remaining rankings have been unchanged.

Table C-4. Price Premium Charged for New, Residential Customer-Driven Renewable 

Power, December 2012 

Rank Utility Net Premium

1 City of Ponca (Oklahoma) -0.87¢/kWh

2 Public Service Co. of New Mexico 0.04¢/kWh

3 Edmond Electric 0.14¢/kWh

4 Indianapolis Power & Light Co. 0.15¢/kWh

5 Avista Corp. (Washington and Idaho) 0.33¢/kWh

6 Arizona Public Service 0.40¢/kWh

7 Xcel Energy (Minnesota only) 0.66¢/kWh

8 Oklahoma Gas & Electric Co. 0.86¢/kWh

9 Connecticut Light and Power Co. / United Illuminating 0.99¢/kWh

10 CPS Energy 1.00¢/kWh

10 WPPI Energy 1.00¢/kWh

The average net premium for City of Ponca over 2012 was -0.08¢/kWh.
58 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.

Table C-5. Customer Participation Rate, December 2012 

Rank Utility Customer Participation Rate

1 City of Palo Alto (California) 18.2%

2 Portland General Electric 12.4%

3 Madison Gas & Electric Co. 9.4%

4 Sacramento Municipal Utility District 9.2%

5 City of Naperville (Illinois) 7.6%

6 Pacific Power (Oregon) 7.6%

7 Silicon Valley Power 6.9%

8 River Falls Municipal Utilities 6.1%

9 Stoughton Utilities 5.1%

10 Cuba City Light & Water 5.0%