Technical Report

NREL/TP-6A2-46581

September 2009

Green Power Marketing in the 

United States: A Status Report 

(2008 Data) 

Lori Bird, Claire Kreycik, and Barry Friedman
National Renewable Energy Laboratory

1617 Cole Boulevard, Golden, Colorado 80401-3393

303-275-3000 • www.nrel.gov

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

Office of Energy Efficiency and Renewable Energy

Operated by the Alliance for Sustainable Energy, LLC

Contract No. DE-AC36-08-GO28308

Technical Report

NREL/TP-6A2-46581

September 2009

Green Power Marketing in the 

United States: A Status Report 

(2008 Data) 

Lori Bird, Claire Kreycik, and Barry Friedman

Prepared under Task No. SAO9.3004
NOTICE

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iii

Acknowledgments

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

and Renewable Energy (EERE). The authors wish to thank Linda Silverman and the EERE 

technology programs for their support of this work. The authors also wish to thank Blaine 

Collison of the U.S. Environmental Protection Agency; Rob Harmon of the Bonneville 

Environmental Foundation; Alex Pennock and Jane Valentino of the Center for Resource 

Solutions; Dan Lieberman and Gabe Petlin of 3Degrees Inc.; and Jim Newcomb, Gian Porro, and 

Jenny Sumner of NREL for their thoughtful review of the document; as well as Michelle Kubik 

of NREL for her 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 U.S. DOE’s Green 

Power Network Web site at http://greenpower.energy.gov.
iv

List of Acronyms

aMW average megawatt

DOE Department of Energy

EEPS energy efficiency portfolio standards

EIA Energy Information Administration

EPA Environmental Protection Agency

ESC energy savings certificate

FCA fuel-cost adjustment

kWh kilowatt-hour

M&V measurement and verification

MW megawatt

MWh megawatt-hour

NREL National Renewable Energy Laboratory

NYSERDA New York State Energy Research and Development Authority

OG&E Oklahoma Gas & Electric

PG&E Pacific Gas & Electric

REC renewable energy certificate

RGGI Regional Greenhouse Gas Initiative

RPS renewable portfolio standard

TRC tradable renewable certificates
v

Table of Contents

List of Figures................................................................................................................................. v

List of Tables ................................................................................................................................. vi

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

Green Power Market Summary and Trends.................................................................................... 3

Green Power Sales...................................................................................................................... 3

Customer Participation................................................................................................................ 5

Comparison of Voluntary and Compliance Markets.................................................................. 6

Utility Green Pricing....................................................................................................................... 8

Green Pricing Products and Premiums....................................................................................... 8

Green Pricing Customer Participation ...................................................................................... 10

Green Pricing Renewable Energy Sales ................................................................................... 11

Competitive Green Power and REC Markets............................................................................... 14

REC and Competitive-Market Products and Pricing................................................................ 15

REC and Competitive-Market Customer Participation ............................................................ 16

REC and Competitive-Market Green Power Sales................................................................... 18

The Voluntary Carbon Offsets Market ......................................................................................... 20

Voluntary Green Power Market Trends and Issues...................................................................... 22

Program Marketing Expenditures: Finding the Right Balance................................................. 22

Renewable Energy Certificate Prices........................................................................................ 27

Regional REC Supply and Demand Balances.......................................................................... 30

Conclusions and Observations...................................................................................................... 32

References..................................................................................................................................... 33

Appendix A. Estimates of Renewable Energy Capacity Serving Green Power Markets, 

2000-2004................................................................................................................................. 35

Appendix B. Top 25 Purchasers in the U.S. EPA Green Power Partnership, July 2008.............. 36

Appendix C. Estimated U.S. Green Pricing Customers by State and Customer Class, 

2005 and 2006 .......................................................................................................................... 37

Appendix D. Utilities Offering Green Pricing Programs in Regulated Markets, 2007 ................ 39

Appendix E. Links to Utility Green Pricing Programs and REC and Competitive-Market 

Green Power Offerings ............................................................................................................ 41

Appendix F. Top Ten Utility Green Pricing Programs ................................................................ 42

List of Figures

Figure 1. Estimated Green Power Sales By Renewable Energy Source, 2008............................... 3

Figure 2. Comparison of Voluntary and Compliance Markets for Renewable Energy, 2004-2008 . 7

Figure 3. Trends in Utility Green Pricing Premiums, 2000-2008................................................... 9

Figure 4. Annual Sales of Renewable Energy Through Utility Green Pricing Programs 

(Regulated Electricity Markets Only), Millions of Kwh ........................................................ 12

Figure 5. Growth in Retail Sales and Customer Participation for Utility/Marketer Partnerships

in Competitive Markets, 2005-2008 ....................................................................................... 17

Figure 6. Average Program Marketing and Administration Expenditures By Utility Size, 2008... 22

Figure 7. Compliance Market (Primary Tier) REC Prices, 2006 to Mid-2009 ............................ 27

Figure 8. Voluntary REC Prices, 2006 to Mid-2009 .................................................................... 29

Figure 9. Snapshot of Regional Demand and Supply Under The Two Cases in 2015 (GWh)..... 31
vi

List of Tables 

Table 1. Estimated Annual Green Power Sales by Market Sector, 2005-2008 .............................. 4 

Table 2. Estimated Annual Green Power Sales by Customer Segment, 2005-2008 ...................... 4 

Table 3. Estimated Annual Green Power Sales by Customer Segment and Market Sector, 2008 . 5 

Table 4. Estimated Cumulative Renewable Energy Capacity Supplying Green Power Markets, 

2005-2008 ................................................................................................................................. 5 

Table 5. Estimated Cumulative Green Power Customers by Market Segment, 2002-2008 ........... 6 

Table 6. Residential Price Premiums of Utility Green Power Products (¢/kWh), 2001-2008 ....... 9 

Table 7. Estimated Cumulative Number of Customers Participating in Utility Green Pricing 

Programs (Regulated Electricity Markets Only), 2001-2008 ................................................. 10 

Table 8. Customer Participation Rates in Utility Green Pricing Programs, 2002-2008. .............. 11 

Table 9. Annual Sales of Renewable Energy through Utility Green Pricing Programs 

(Regulated Electricity Markets Only), Millions of kWh, 2002-2008 ..................................... 12 

Table 10. Average Purchases of Renewable Energy per Customer (kWh per Year), 2002-2008 12 

Table 11. Renewable Energy Generation and Capacity Supplying Green Pricing 

Programs, 2008 ....................................................................................................................... 13 

Table 12. Renewable Energy Sales as a Percent of Utility Electricity Sales, 2007-2008 ............ 13

Table 13. Total Retail Sales of Green-e Energy Certified Renewable Energy, 2007 and 2008, 

Millions of kWh ...................................................................................................................... 16

Table 14. Estimated Cumulative Number of Customers Buying RECs or Green Power 

from Competitive Marketers, 2003-2008 ............................................................................... 17

Table 15. Retail Sales of Renewable Energy in Competitive Markets and RECs, 

Millions of kWh, 2004-2008 ................................................................................................... 18

Table 16. Renewable Energy Sources Supplying Competitive and REC Markets, 2008 ............. 19 

Table 17. GHG Offsets Sources from U.S.-Based Renewable Energy Sources, 2008 ................. 21 

Table 18. Compliance Market SREC Prices, 2009 ....................................................................... 28 

Table 19. Range of Voluntary REC Prices in 2008 for Different Vintages ($/MWh) ................. 29 

Table A-1. Estimate Cumulative New Renewable Energy Capacity Supplying Green Power 

Markets, 2000-2004 ................................................................................................................ 35 

Table B-1. Top 25 Purchasers in the U.S. EPA Green Power Partnership ................................... 36 

Table C-1. Estimated U.S. Green Pricing Customers by State and Customer Class, 2006 and 

2007......................................................................................................................................... 37 

Table C-2. Estimated U.S. Green Pricing Customers by Customer Class, 2002-2007 ................ 38 

Table D-1. Utilities Offering Green Pricing Programs in Regulated Markets, 2008 ................... 39 

Table D-2. Utility/Marketer Green Power Programs in Restructured Electricity Markets, 2008 ... 40 

Table F-1. Green Pricing Program Renewable Energy Sales (as of December 2008) ................. 42 

Table F-2. Total Number of Customer Participants (as of December 2008) ................................ 43 

Table F-3. Customer Participation Rate (as of December 2008). ................................................. 44 

Table F-4. Green Power Sales as Percentage of Total Retail Electricity Sales 

(as of December 2008). ........................................................................................................... 45 

Table F-5. Price Premium Charged for New, Customer-Driven Renewable Power 

(as of December 2008). ........................................................................................................... 46
1

Introduction

Voluntary consumer decisions to buy electricity supplied from renewable energy sources 

represent a powerful 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.1

Since then, these products have become more prevalent, both from traditional utilities and from 

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

electricity markets or offering renewable energy certificates (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.

More than 850 utilities, or about 25% of utilities nationally, offer green power programs to 

customers. These programs allow customers to purchase some portion of their power supply as 

renewable energy—almost always at a higher price—or to contribute funds for the utility to 

invest in renewable energy development. The term “green pricing” is typically used to refer to 

these utility programs offered in regulated or noncompetitive electricity 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.2

Nearly a dozen states that have opened their markets to retail competition have experienced some 

green power marketing activity. 

Finally, regardless of whether they have access to a green power product from their retail power 

provider, any consumer can purchase green power through renewable energy certificates (RECs), 

which represent the “environmental attributes” of electricity generated from renewable energybased projects. Consumers can also support renewable energy development through REC 

purchases without having to switch to an alternative electricity supplier. Today, several dozen 

companies actively market RECs to residential or business customers throughout the United 

States. Many REC marketers also sell greenhouse gas emissions offsets sourced from renewable 

energy projects.

This report documents green power marketing activities and trends in the United States. First, we 

present aggregate green power sales data for all voluntary purchase markets across the United 

States. The next three sections provide summary data on 1) utility green pricing programs 

offered in regulated electricity markets; 2) green power marketing activity in competitive 

electricity markets, as well as green power sold to voluntary purchasers in the form of RECs; and 

3) renewable energy sold as greenhouse gas offsets in the United States. These sections are 

 1 The term "green power" generally refers to electricity supplied in whole or in part from renewable energy sources, 

such as wind and solar power, geothermal, hydropower (typically low-impact or small hydro), and various forms of 

biomass. 

2 Under these programs, consumers can buy renewable energy from independent renewable energy marketing 

companies without switching their electricity service from the default or standard-offer service provider. 
2

followed by a discussion of key market trends and issues. The final section offers conclusions 

and observations. The data presented in this report are based on figures provided to NREL by 

utilities and independent renewable energy marketers.3

 3 Green power market data for previous years are available in Bird et al. (2008), Bird et al. (2007), Bird and Swezey 

(2006), Bird and Swezey (2005a), Bird and Swezey (2004), Bird and Swezey (2003), Swezey and Bird (2000), and 

Swezey and Bird (1999). 
3

Green Power Market Summary and Trends

Green Power Sales

Overall, retail sales of renewable energy in voluntary purchase markets exceeded 24 billion 

kilowatt-hours (kWh) in 2008, or about 0.6% of total U.S. electricity sales.

4 This includes sales 

of renewable energy derived from both “new” and “existing” renewable energy sources, 

consistent with the generally accepted market definition,5 with most sales supplied from new 

sources. In 2008, renewable energy sources supplied about 85% of renewable energy sold into

voluntary purchase markets.

6 In addition, greenhouse gas offsets sourced from new renewable 

energy resources—totaling nearly 250,000 tons of CO2 equivalent—were sold to U.S. voluntary 

purchasers in 2008.

Wind energy represented 71% of total green power sales; followed by biomass energy sources, 

including landfill gas (17%); hydropower (primarily low impact or small hydro) (9%);

geothermal (2%); solar (<1%); and unknown sources (1%) (Figure 1). Based on the sales data 

presented in this report, we estimate the market value of green power sales in 2008 to be between 

$110 million and $190 million.

LFG/Biomass

17%

Geothermal

2%

Hydro

9%

Solar

0.1%

Wind

71%

Unreported

1%

Figure 1. Estimated green power sales by renewable energy source, 2008

 4 U.S. electricity sales totaled 3,765 billion kWh in 2007 (2008 data are not yet available), according to the U.S. 

Energy Information Administration (EIA). See http://www.eia.doe.gov/cneaf/electricity/epa/epat7p2.html. The 

remaining renewable energy generation is rate-based by utilities or used to meet renewable portfolio standards. 5With green power, a distinction is often made based on the vintage of the renewable energy generator. The green 

power industry generally follows the Green-e Energy National Standard, which defines a “new” renewable 

generation facility as one placed in operation or repowered on or after January 1, 1997. Therefore, an “existing” 

generation facility is one placed in service before January 1, 1997. For more information on the Green-e Energy

National Standard, see http://www.green-e.org/getcert_re_stan.shtml. 6 Estimates presented in this report are primarily based on data provided by utilities and marketers and supplemented 

with other available data. Because we are unable to obtain data from all market participants, the estimates presented 

here likely underestimate the size of the entire market.
4

Green power sales (in kilowatt-hours) increased by 34% in 2008, with annual average growth of 

41% since 2004 (Table 1). REC sales have been driving much of the growth, increasing 47% in 

2008. Overall, REC markets represent nearly two-thirds of industry sales.7 Sales in competitive 

markets and green pricing program grew moderately in 2008; green pricing sales were dampened 

by the termination of one of the largest programs (Florida Power and Light Sunshine Energy 

Program). 8 

Sales to nonresidential customers continued to outpace those to residential consumers, with more 

than three-quarters of all sales by volume to the nonresidential sector in 2008 (Table 2). Nearly 

all REC sales were to business and institutional customers, while residential customers played a 

larger role in green pricing programs and competitive markets, where they accounted for more 

than 50% of renewable energy sales (Table 3). 

Table 1. Estimated Annual Green Power Sales by Market Sector, 2005-2008* 

(Millions of kWh)

Market Sector 2005 2006 2007 2008

% Change 

2004/2005

% Change 

2005/2006

% Change 

2006/2007

% Change 

2007/2008

Utility Green Pricing 2,500 3,400 4,300 4,800 33% 39% 25% 12%

Competitive Markets 2,200 1,700** 3,200 3,900 -19% -20%** 88%** 22%

REC Markets*** 3,900 6,800 10,600 15,600 126% 75% 55% 47%

Retail Total 8,500 11,900 18,100 24,300 37% 41% 53% 34%

*Includes sales of new and existing renewable energy. Totals and growth rates may not calculate due to rounding. 

**2006 sales figures may be underestimated because of data gaps. 

***Includes only RECs sold to end-use customers separate from electricity. 

Table 2. Estimated Annual Green Power Sales by Customer Segment, 2005-2008* 

(Millions of kWh)

Customer Segment 2005 2006 2007 2008

% Change 

2005/2006

% Change 

2006/2007

% Change 

2007/2008

Residential 3,000 3,200 4,500 5,500 8% 39% 22%

Nonresidential 5,500 8,700 13,600 18,800 58% 56% 38%

Total 8,500 11,900 18,100 24,300 41% 53% 34%

% Nonresidential 65% 73% 75% 77% -- -- --

 *Totals and growth rates may not compute due to rounding. 

 

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 these other categories. 8 The Florida Public Service Commission (PSC) initially acted to discontinue the program as a result of concerns 

over the amount of program revenues spent on marketing compared to expenditures on the renewable energy 

resources used to supply the program, as well as its support for out-of-state resources. However, the final basis for 

the decision to terminate the program, after a subsequent program audit, was related to the commission’s assessment 

that a voluntary program was not needed after the Florida Legislature mandated an RPS. By Order No. PSC-08-

0600-PAA-EI, issued September 16, 2008, in Docket No. 070626-EI, the commission terminated the program. 

http://www.floridapsc.com/library/filings/08/08720-08/08-0600.ord.doc
5

At the end of 2008, kilowatt-hour sales of renewable energy in voluntary markets represented a 

generating capacity equivalent of about 7,300 MW, with about 6,300 MW of that from “new” 

renewable energy sources (Table 4).9 Since 2000, the amount of renewable energy capacity 

serving green power markets has increased more than 40-fold (see Appendix A).

Table 3. Estimated Annual Green Power Sales by Customer Segment and Market Sector, 2008

(Millions of kWh)

Customer Segment

Green 

Pricing

Competitive 

Markets

REC 

Markets Total

Residential 2,600 2,700 200 5,500

Nonresidential 2,100 1,200 15,400 18,700

Total 4,700 3,900 15,600 24,300

% Residential 55% 69% 1% 23%

Note: Totals may not add due to rounding.

Table 4. Estimated Cumulative Renewable Energy Capacity Supplying Green Power Markets, 

2005-2008 (Megawatts)

Market

2005 Total 

Renewables 

Capacity

2005 *New* 

Renewables 

Capacity

2006 Total 

Renewables 

Capacity

2006 “New” 

Renewables 

Capacity

2007 Total 

Renewables 

Capacity

2007 “New” 

Renewables 

Capacity

2008 Total 

Renewables 

Capacity

2008 *New” 

Renewables 

Capacity

Utility Green Pricing 800 700 1,100 1,000 1,400 1,300 1,500 1,400

Competitive 

Markets/RECs 1,700 1,300 2,400 2,100 3,700 3,000 5,800 4,900

Total 2500 2000 3,500 3,100 5,100 4,300 7,300 6,300

Note: “New” renewables capacity is a subset of total renewables capacity supplying green power markets. 

Customer Participation 

Based on our estimates, nearly one million electricity customers nationwide purchased green 

power products in 2008 through regulated utility companies, from green power marketers in a

competitive-market setting, or in the form of RECs (Table 5).10 Utility green pricing programs 

have shown continued customer growth as the number of utility programs has increased and as 

existing programs have grown; however, in 2008, customer numbers did not grow in aggregate. 

This is largely due to the cancellation of the Florida Power and Light (FPL) Sunshine Energy 

Program, a large program with more than 35,000 participants prior to its termination.

Competitive-market green power participation has expanded during the past few years but has

been less consistent over time, as some markets have grown and then contracted (such as in 

 9 Capacity estimates are calculated based on reported green power kilowatt-hours sales assuming capacity factors 

for each renewable resource type. For wind, a capacity factor of 33% was assumed, 90% for landfill gas, 80% for 

biomass, 96% for geothermal, 40% for hydroelectric, and 15% for solar electric.

10 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 2006 and 2007, see data from U.S. EIA 2008 in 

Appendix C. 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% to 2%).
6

California and Pennsylvania). The most recent growth in competitive markets has been 

concentrated in Texas and northeastern states. In 2008, the number of customers buying RECs 

increased from more than 10,000 to about 30,000, but it still represents a small fraction of the 

total green power market on a customer basis (but not a kilowatt-hour basis). Despite the limited 

number of residential customers purchasing RECs, REC sales represent nearly two-thirds of all 

green power kilowatt-hour sales and have grown dramatically in recent years as a result of 

several very large purchases (see Appendix B for a list of top green power purchasers).

Table 5. Estimated Cumulative Green Power Customers by Market Segment, 2002-2008 

2002 2003 2004 2005 2006 2007 2008

Utility Green Pricing 230,000 270,000 330,000 390,000 490,000 550,000 550,000

Competitive Markets ~150,000 >170,000 >140,000 >180,000 ~210,000 300,000 390,000

REC Markets* < 10,000 < 10,000 < 10,000 < 10,000 ~10,000 >10,000 30,000

Retail Total ~390,000 ~450,000 ~480,000 ~580,000 ~710,000 ~860,000 ~970,000

% Change ~39% ~15% ~7% ~21% ~22% ~21% 13%

Note: 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. 

*Includes only end-use customers purchasing RECs separate from electricity. 

Average participation rates among utility green pricing programs increased slightly from 2.0% to 

2.2% in 2008, with a median value of 1.2%; top performing programs have achieved rates 

ranging from 5% to 21%. Competitive markets have experienced green power customer 

penetration rates ranging from 1% to 2% in the states with the most active markets; however, 

participation in competitive markets has been subject to market conditions and rules, and has 

been more volatile than in traditionally regulated markets.

Comparison of Voluntary and Compliance Markets

In 29 states and the District of Columbia, renewable portfolio standard (RPS) policies require 

that utilities or load-serving entities include a certain percentage of renewable energy within their 

power generation mix; the percentages required and eligibility requirements vary among the

states. Eligible renewable energy may either be purchased by load-serving entities to meet their 

RPS requirements, or may be bought by consumers or businesses wanting to buy renewable 

energy on a voluntary basis. However, green power certification programs and state RPS policy 

rules generally ensure that there is no double counting between the two markets (i.e., that the 

same kilowatt-hour is not used for more than one purpose).

11 Ensuring the absence of doublecounting is important to the integrity of the market in that consumers who pay a premium for 

green power want to support renewable energy that would not have been otherwise supported 

through regulatory requirements. 

In 2008, state RPS policies collectively called for utilities to procure about 23 billion kWh of 

“new” renewable energy generation (Barbose 2009), compared to about 24 billion kWh sold into 

 11 For additional detail on the treatment of voluntary green power purchases in state RPS policies, see Holt and 

Wiser 2007. 
7

the voluntary green power market.

12 Figure 2 shows that between 2004 and 2008, voluntary 

market demand for renewables slightly exceeded compliance market demand for new 

renewables. However, renewable energy demand to meet RPS policies is expected to grow 

rapidly in coming years. By 2010, RPS policies collectively call for utilities to obtain more than 

60 billion kWh of new renewables, increasing to about 100 billion kWh in 2012; voluntary 

market growth rates would have to increase to keep pace.

13 

0

5,000

10,000

15,000

20,000

25,000

2004 2005 2006 2007 2008

millions of kWh annually

Voluntary

Compliance (new

renewables)

 Note: Compliance market data sourced from Lawrence Berkeley National Laboratory 

 (LBNL) (Barbose 2009)

Figure 2. Comparison of voluntary and compliance markets for renewable energy, 2004-2008

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

to 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. 

13 This figure does not include the Kansas RPS because the Kansas Corporation Commission has not yet developed 

the methodology for calculating utility’s peak demand, so the amount of renewable generation required to meet the 

RPS is not yet known.
8

Utility Green Pricing

This section provides information specific to utility green pricing programs, a subset of the 

market. The number of utilities offering green pricing has grown steadily in recent years—today, 

more than 850 investor-owned, public, and cooperative utilities in most states offer green pricing 

programs. Appendix D provides a list of utilities offering green pricing, and Appendix E

provides Web links to all green power product offerings.

14 Because a number of small municipal 

or cooperative utilities offer programs developed by their power suppliers, the number of distinct 

green pricing programs is about 160. Some states have adopted laws requiring utilities to offer 

consumers green power options, which have driven the development of new programs in some 

states.

15

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. 

In 2008, the price of green power for residential customers in utility programs ranged from 

-1.0¢/kWh (a savings compared to standard service) to 8.8¢/kWh above standard electricity 

rates, with an average premium of 1.8¢/kWh and median of 1.5¢/kWh. These premiums have 

been adjusted to account for any fuel-cost exemptions granted to green power program 

participants.16 In 2008, the utility programs with the lowest premiums for energy derived from 

new renewable sources had premiums ranging from -1.0¢/kWh (a savings) to 0.9¢/kWh. On 

average, consumers spend about $5.40 per month above standard electricity rates for green 

power through utility programs, which is consistent with previous years. 

Since 2000, the average price premium has dropped at an average annual rate of Table 6; 

Figure 3). Some of this reduction can be attributed to lower market costs for renewable energy 

supplies, although changes in market conditions since mid-2008 have made these trends less 

clear. In recent years, increases in the price of natural gas narrowed the price gap between 

renewables and gas-fired generation alternatives, leading to lower initial premiums for many new 

programs; however, since the economic downturn in mid- to late-2008, natural gas prices have 

fallen dramatically, reversing this trend. Although wind was generally competitive with 

wholesale power prices in 2008, a drop in these prices may pose additional challenges for its 

8% (

 

14 For an up-to-date list of utilities with green pricing programs, see the U.S. Department of Energy’s Green Power 

Network Web site at http://apps3.eere.energy.gov/greenpower/markets/pricing.shtml?page=1. 15 These states include Colorado, Iowa, Minnesota, Montana, New Mexico, Oregon, Vermont, and Washington. 16 For example, some utilities exempt green pricing customers from monthly or periodic fuel charges imposed to pay 

higher than expected fossil-fuel costs. For a more detailed discussion of this topic, see Bird et al. (2008). 
9

competitiveness in 2009 (Wiser and Bolinger 2009). The competitiveness of wind and other 

renewables with conventional generation, as well as regional demand from state renewable 

energy standards (and national demand if a federal standard is adopted), will affect premiums in 

coming years.

Table 6. Residential Price Premiums of Utility Green Power Products (¢/kWh), 2001-2008

2001 2002 2003 2004 2005 2006 2007* 2008*

Average 

Premium 2.93 2.82 2.62 2.45 2.36 2.12 1.85 1.8

Median Premium 2.5 2.5 2 2 2 1.78 1.5 1.5

Range of 

Premiums 0.9-17.6 0.7-17.6 0.6-17.6

0.33 - 

17.6 (0.7)-17.6 (0.1)-17.6 0.09-7.5 (-1.0)-8.8

10 Programs 

with Lowest 

Premiums** 1.0-1.5 0.7-1.5 0.6-1.3 0.33-1.0 (0.7)- 0.9 (0.1)-1.0 0.09-0.8 (-1.0)-0.9

Number of 

Programs 

Represented 60 80 91 101 104 97 71 86

*In later years, calculations of premiums w ere based on programs that responded to the questionnaire. In previous years, a larger sample 

of programs w as used to calculate the premium, as data w ere available.

**Represents the 10 utility programs w ith the low est price premiums for new customer-driven renew able energy. This includes only 

programs that have installed—or announced firm plans to install or purchase pow er from—new renew able energy sources. In 2001 the 

discrepancy betw een the low end of the range for all programs and the Top 10 programs results from the program w ith the low est 

premium (0.9¢/kWh) not being eligible for the Top 10 because it w as either selling some existing renew ables or had not installed any new 

renew able capacity for its program.

0

0.5

1

1.5

2

2.5

3

3.5

4

2000 2001 2002 2003 2004 2005 2006 2007 2008

Residential Premium, cents/kWh

Average

Median

Figure 3. Trends in utility green pricing premiums, 2000-2008
10

Green Pricing Customer Participation

At the end of 2008, about 550,000 customers were participating in utility green pricing programs 

in regulated electricity markets (Table 7).17 As in the past, a relatively small number of green 

power programs account for the majority of customers, with just 10 programs accounting for 

almost 70% of all participants (Appendix F).

18 From 2001 to 2007, the number of customer 

participants increased more than threefold, but this trend reversed in 2008. With the cancellation 

of the large FPL program, nearly 40,000 customers left the market, and total participants in 

utility programs nationwide fell slightly. Without the loss of the FPL program, the number of 

participants in utility green power programs would have grown modestly, by about 6%.

19 

The decline in the economy, particularly in the second half of 2008, likely contributed to smaller 

gains in participants relative to previous years and a number of programs reported losses in the 

total number of participants. Perhaps surprisingly, nonresidential participant growth was on par 

with 2007; while the reason for this increase is unclear, one possible explanation could be 

heightened interest in renewable energy issues in an election year in which renewables and 

climate change were a focus. It is also possible that some programs placed greater emphasis on 

attracting commercial customers to make up for residential customer losses, as a number of 

programs that reported losing residential customers, reported overall gains in sales as a result of 

increased nonresidential sales. 

Table 7. Estimated Cumulative Number of Customers Participating in Utility Green Pricing 

Programs (Regulated Electricity Markets Only)

Customer Segment 2001 2002 2003 2004 2005 2006 2007 2008

Residential 166,300 224,500 258,700 323,700 383,400 470,800 526,700 519,700

Nonresidential 2,500 3,900 6,500 8,100 11,300 15,500 20,200 26,100

Total 168,800 228,400 265,200 331,800 394,700 486,300 546,900 545,800

% Total Annual Growth 27% 35% 16% 25% 19% 23% 12% 0%

% Residential Growth 27% 35% 15% 25% 18% 23% 12% -1%

% Nonresidential Growth 47% 56% 67% 25% 40% 37% 30% 29%

Table 7 delineates residential and nonresidential customer participation in utility green pricing 

programs over time. The vast majority of participants are residential customers, with 

 17 NREL obtained consumer response data for about two-thirds of utility green pricing programs in 2008, including 

all of the major programs. The remaining programs, which are smaller in size, do not have a large impact on overall 

participant numbers. Wherever possible, other sources and previously reported data were used to estimate data gaps. 18 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 renewables development. These lists can be found at 

http://apps3.eere.energy.gov/greenpower/markets/pricing.shtml?page=3. 19 The Florida Public Service Commission (PSC) initially acted to discontinue the program as a result of concerns 

over the amount of program revenues spent on marketing compared to expenditures on the renewable energy 

resources used to supply the program, as well as its support for out-of-state resources. However, the final basis for 

the decision to terminate the program, after a subsequent program audit, was related to the commission’s assessment 

that a voluntary program was not needed after the Florida Legislature mandated an RPS. By Order No. PSC-08-

0600-PAA-EI, issued September 16, 2008, in Docket No. 070626-EI, the commission terminated the program. 

http://www.floridapsc.com/library/filings/08/08720-08/08-0600.ord.doc
11

nonresidential customers accounting for only 5% of all participants. However, nonresidential 

participation is growing at a faster rate than residential participation, which is having a 

significant positive impact on overall sales volume because of the larger size of nonresidential 

purchases.

At the end of 2008, the average participation rate in utility green pricing programs among 

eligible utility customers was 2.2%, with a median of 1.2% (Table 8). These industry-wide rates 

have shown little change in recent years. The overall lack of improvement in participation rates 

results from a number of factors, including a customer unwillingness to pay a premium for green 

power, and varied levels of interest among utilities in marketing and promoting the program 

(Holt and Holt 2004, Swezey and Bird 2001). However, the top-performing programs continue to 

show improvement, with participation rates ranging from about 5% to 21% in 2008, compared to 

a range of 3% to 6% in 2002. The 20% participation threshold was exceeded for the first time in 

2007. 

Table 8. Customer Participation Rates in Utility Green Pricing Programs, 2002-2008

Participation Rate 2002 2003 2004 2005 2006 2007 2008

Average 1.2% 1.2% 1.3% 1.5% 1.8% 2.0% 2.2%

Median 0.8% 0.9% 1.0% 1.0% 1.0% 1.3% 1.2%

Top 10 Programs 

3.0% -

5.8%

3.9% -

11.1%

3.8% -

14.5%

4.6% -

13.6%

5.1% - 

16.9%

5.2%-

20.4%

5.0% - 

21.0%

In 2008, utilities reported that an average of 5.5% and a median of 2.5% of customers dropped 

out of green pricing programs. Retention rates are still relatively high despite the fact that 

electricity and energy prices remained high in most regions of the country throughout most of the 

year. This finding suggests that customers tend to be “sticky” and maintain participation in green 

power programs, despite electricity and other energy cost increases. While data on the reason for 

dropouts is not available, anecdotal evidence from some utilities suggests that customer moves 

can be a significant source of dropouts. Most utilities (about 70%) do not impose minimum 

periods for which customers must subscribe to the green power program. If a minimum term is 

imposed, it is most commonly one year—although there are several programs that offer fixedprice green power for contracts of longer durations. 

Green Pricing Renewable Energy Sales 

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

two years, in particular. Collectively, utilities in regulated electricity markets sold about 4.8

billion kWh of green power to customers in 2008 (Table 9). Green pricing program sales to all 

customer classes grew by 11% in 2008, compared to rates ranging from 26% to 56% in recent 

years (Table 9 and Figure 4). The loss of the FPL program had a noticeable impact on sales. 

Without the termination of the FPL program, utility green pricing program sales would have 

grown at a rate of 22% in 2008, similar to growth in 2007.

Sales growth is mostly attributed to increases in the number of nonresidential customers and 

larger purchases; in 2008, the average nonresidential purchase nearly doubled from the 2007 

average (Table 10). Although the reason for these increased purchases is not known, it could be 
12

attributed to declines in green power prices for nonresidential retail customers, or enrollment of 

larger commercial and industrial customers. As noted earlier, some programs may have also 

placed greater emphasis on marketing to the commercial sector to make up for residential 

customer losses. 

Table 9. Annual Sales of Renewable Energy through Utility Green Pricing Programs 

(Regulated Electricity Markets Only), Millions of kWh, 2002-2008

2002 2003 2004 2005 2006 2007 2008

Sales to 

Residential 660 870 1,300 1,610 2,100 2,550 2,660

Sales to 

Nonresidential 230 410 540 840 1,300 1,630 2,150

Total Sales to 

All customers 900 1,280 1,840 2,450 3,400 4,290 4,810

% Annual 

Growth in Total 56% 43% 43% 33% 39% 26% 12%

% Nonresidential 

of Total Sales 26% 32% 30% 34% 38% 38% 32%

 Note: Totals may not add due to rounding. 

0

1,000

2,000

3,000

4,000

5,000

6,000

2002 2003 2004 2005 2006 2007 2008

Sales (millions of kWh)

Residential Sales

Nonresidential Sales

Total Sales

Figure 4. Annual sales of renewable energy through utility green pricing programs, 2002-2008

(regulated electricity markets only)

Table 10. Average Purchases of Renewable Energy per Customer (kWh per Year), 2002-2008

2002 2003 2004 2005 2006 2007 2008

Residential Customers 2,900 3,400 4,000 4,200 4,400 4,900 5,500

Nonresidential Customers 60,000 63,100 67,200 74,500 85,700 77,400 141,300

All Customers 3,900 4,800 5,500 6,200 6,700 7,400 20,800
13

About 95% of the renewable energy sold to consumers through green pricing programs was 

supplied from projects meeting the generally accepted industry definition of “new.” Renewable 

energy sold through green pricing programs in 2008 represents an equivalent renewable energy 

capacity of more than 1,500 MW, with more than 1,400 MW of this represented by “new” 

renewable energy resources (Table 11).

20

Table 11. Renewable Energy Generation and Capacity Supplying Green Pricing Programs, 2008

Wind, solar, landfill gas, and other biomass are the 

renewable resources most commonly included in utility programs; although solar, in particular, 

may be used to supply a small fraction of kilowatt-hour sales. Wind energy represents the largest 

portion of the total capacity. In 2007, sales of renewable energy through green pricing programs 

represented more than 1,400 MW of renewable energy capacity, with about 1,300 MW of that 

from new renewable energy sources. Table 4 and Appendix A present estimates of new capacity 

serving green pricing programs in earlier years.

Landfill 

Gas

Other 

Biomass

Geothermal Hydro Solar Wind Unknown Total

Sales MWh 343,000 202,000 75,000 52,000 9,000 3,993,000 143,000 4,817,000

% of Total Sales 7% 4% 2% 1% 0.2% 83% 3% 100%

Total MW 44 29 9 15 7 1,381 33 1,517

MW New RE 41 28 9 14 7 1,341 - 1,440

In 2008, green power sales represented a small but increasing proportion of a utility company’s 

overall energy sales. Table 12 shows that, on average, renewable energy sold through green 

pricing programs in 2008 represented approximately 1% of total utility electricity sales (on a 

kWh basis), while a few utilities reported fractions as high as about 5% to 6% of total retail 

electricity sales. On a residential basis, green power sales represented a higher fraction of total 

utility electricity sales, with one utility reporting a fraction as high as 23%. 

Table 12. Renewable Energy Sales as a Percent of Utility Electricity Sales, 2007-2008

Customer Class Avg. Med. Range Avg. Med. Range

Residential 1.4% 0.6% 0% - 17.4% 1.5% 0.5% 0% - 23.4%

Nonresidential 0.5% 0.2% 0% - 6.3% 0.8% 0.2% 0% - 12.0%

All customers 0.8% 0.3% 0% - 5.7% 1.0% 0.4% 0% - 6.4%

2007 2008

 20 Capacity estimates are calculated based on reported green power kilowatt-hours sales assuming capacity factors 

for each renewable resource type. For wind, a capacity factor of 33% was assumed, 90% for landfill gas, 80% for 

biomass, 96% for geothermal, 40% for hydroelectric, and 15% for solar electric. Estimates of megawatts in previous 

years’ projections were higher on a relative basis due to the capacity factor assumed for wind. In prior years a 30% 

capacity factor was assumed, but in 2008 estimates of MW were based on a 33% capacity factor to reflect 

improvements in capacity factors as a result of the movement toward larger turbines as well as greater reliance on 

projects in areas with strong wind resources. For every million MWh, this accounts for a discrepancy of 35 MW of 

capacity in the estimates.
14

Competitive Green Power and REC Markets

This section provides greater detail on green power sold in competitive (or restructured) 

electricity markets as well as in the form of RECs—subsets of the entire green power market. 

About one-quarter of U.S. states have restructured their electricity markets for retail service 

competition. Currently, electricity consumers in the following states can purchase competitively 

marketed green power: Connecticut, Illinois, Maine, Maryland, Massachusetts, New Jersey, New 

York, Pennsylvania, Rhode Island, Texas, and the District of Columbia.21,22 Competitively 

marketed green power offerings are also available to nonresidential consumers in a few other 

states. 

Initially, buying green power in competitive retail markets entailed switching electricity service 

from the incumbent utility to a green power supplier. However, with few exceptions, green 

power marketers have found it difficult to compete or to persuade customers to switch suppliers. 

As a remedy, a number of states now require default suppliers (which are often the incumbent 

distribution utilities) to offer green power options to their customers. These load-serving entities 

typically provide customers with underlying electricity generation, combined with a choice of 

several green products offered by competing green power marketers. In addition, several utility 

suppliers have voluntarily teamed with a single green power marketer to offer a green power 

option to their customers. Such programs are now offered in Connecticut, Massachusetts, New 

Jersey, New York, Pennsylvania, and Rhode Island.

RECs provide another alternative to switching electricity suppliers. Also known as green 

certificates, green tags, or tradable renewable certificates (TRCs), RECs represent the “green” 

attributes of renewable energy generation and can be sold separately from commodity electricity. 

REC-based products may be supplied from a variety of renewable energy sources throughout the 

country and sold to customers nationally, or they may be supplied from renewable energy 

sources in a particular region or locality and marketed as such to local customers. More than 25 

companies offer certificate-based green power products to retail customers via the Internet, and a 

number of other companies market RECs solely to commercial and industrial customers.

23

RECs are also sold in the wholesale market and are frequently used by utilities and marketers 

who bundle RECs with commodity electricity to sell green power to retail customers. In fact, 

RECs are used to supply most of the programs where default suppliers have teamed with green 

 21 For an up-to-date list of products offered by competitive green power marketers, see the U.S. Department of 

Energy’s Green Power Network Web site at: 

http://apps3.eere.energy.gov/greenpower/markets/marketing.shtml?page=1. 22We do not include Oregon and Virginia in this list. In Oregon, only large commercial and industrial customers are 

able to switch to competitive green power providers; residential and small commercial customers have access to 

green power options offered by the incumbent utilities, which we categorize as green pricing. In Virginia, at least 

one retail electricity provider provided green power options in 2007 and earlier, but does not do so currently. 23 For an up-to-date list of companies offering REC-based green power products, see the U.S. Department of 

Energy’s Green Power Network Web site at: 

http://apps3.eere.energy.gov/greenpower/markets/certificates.shtml?page=1. For a list of REC suppliers serving 

commercial or wholesale customers, see: 

http://apps3.eere.energy.gov/greenpower/markets/certificates.shtml?page=4.
15

power marketers. Therefore, it can be difficult to distinguish REC products from other green 

power offerings. This is particularly true when REC products are supplied from renewable 

sources located in the same region where they are marketed.

REC and Competitive-Market Products and Pricing

Green power products offered in competitive markets 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 

renewables because of a lack of “new” renewable energy supplies, but most marketers now offer 

primarily new renewables. In 2008, about 85% of competitive-market and REC sales were 

supplied from new renewable energy sources. This movement toward increased reliance on new 

renewables has also been encouraged by green power product certification programs, which set 

standards for product quality, and have required increasing amounts of “new” renewables. 

Beginning January 1, 2007, the Green-e Energy certification program began requiring that all 

certified products be supplied exclusively from “new” renewable energy projects.24 Similarly, 

the U.S. Environmental Protection Agency’s (EPA) Green Power Partnership requires its 

partners to purchase “new” renewables to meet its purchase criteria.25 Both Green-e and EPA

define “new” as those facilities put into service on or after January 1, 1997, which is generally 

considered to be the inception of the voluntary green power market.

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

including the price of standard offer or default service, the availability of incentives to green 

power marketers or suppliers, and the cost of renewable energy generation available in the 

regional market. Some marketers have charged prices close to or even below the default market 

price in recent years (e.g., in Texas); 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 of between 

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

ranged from small discounts to a premium of about 10¢/kWh in recent years. 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.

Similar to competitively marketed products, retail prices charged for REC products typically

range from about 1¢/kWh to 2.5¢/kWh for residential and small commercial customers, although 

some are priced as high as 5.5¢/kWh. In most cases, larger customers are able to negotiate lower 

 24 Administered by the San Francisco-based Center for Resource Solutions, the Green-e Energy program certifies 

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

For details on the Green-e Energy National Standard, see the Green-e Web site at: http://www.green-e.org/. 25 See the EPA’s Green Power Web site at: http://www.epa.gov/greenpower. 
16

prices. Nearly all REC products are sourced from new renewable energy generation projects as a 

result of product certification requirements.

REC buyers often seek certification out of concerns over “double counting” and to ensure a level 

of oversight and auditing because RECs are generally not subject to the same regulatory scrutiny

as electricity and mandatory renewable requirements. Table 13 shows Green-e Energy certified 

retail transactions in 2007 and 2008. Green-e Energy certified more than 13 billion kWh of retail 

transactions in 2008. Compared to NREL’s total voluntary market retail sales figure of 24

billion kWh, Green-e Energy certified 54% of voluntary market retail sales (Karelas 2009).

Table 13. Total Retail Sales of Green-e Energy Certified Renewable Energy, 2007 and 2008

(Million kWh)

Year 2007 2008 2007 2008 2007 2008

RECs 82 50 7,305 10,490 7,387 10,540

Green Pricing 834 1,413 367 753 1,201 2,166

Competitive Electricity 148 171 250 170 398 341

Total 1,064 1,634 7,922 11,413 8,986 13,047

Residential Commercial Total Retail

 Source: Karelas 2009

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

exceeded 13 billion kWh in 2008. It is important to note that 8.2 billion kWh sold in certified 

wholesale transactions were resold in Green-e Energy certified retail transactions. The remaining 

4.9 billion kWh were sold in non-Green-e Energy certified transactions, most likely to utilities 

and electric service providers, power marketers, or retail customers.

Removing the instances of renewable energy certified by Green-e Energy at both the wholesale 

and retail levels, Green-e Energy certified sales of 17.4 billion unique kilowatt-hours in 2008. 

This is an increase of 49% from 2007. Assuming that all kilowatt-hours certified at the wholesale 

level were ultimately sold in retail voluntary sales, 74% of the total kilowatt-hours sold in the 

retail voluntary market in 2008 were involved in a Green-e Energy certified transaction at some 

point in their chain of custody. 

REC and Competitive-Market Customer Participation

Based on data received from green power marketers, we estimate that nearly 425,000 retail 

customers were buying green power from competitive suppliers or as unbundled RECs at the end 

of 2008 (Table 14). This number includes nearly 122,000 participants in utility/marketer 

programs available in competitive markets. Participation in utility/marketer partnership programs 

in competitive markets has doubled since 2005, although the number of customers remained 

relatively constant between year-end 2007 and 2008. Figure 5 shows growth both in sales and 

customer participation in utility/marketer programs in competitive markets. Between 2005 and 

2007, sales and customer growth rates were nearly equivalent; but, in 2008, customer numbers 

grew by only 4% compared to 35% growth in sales.
17

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

900,000

1,000,000

2005 2006 2007 2008

Customers

Sales (MWh)

Sales

Customers

Figure 5. Growth in retail sales and customer participation for utility/marketer partnerships in 

competitive markets, 2005-2008

In competitive markets, the vast majority of customers buying green power are residential 

customers. Of the approximately 425,000 retail customers in competitive markets, fewer than 

10% purchase REC-only products. The number of REC-only buyers increased from about 13,000 

to 30,000 customers in 2008, showing some increase in traction with residential consumers—but 

the fraction of overall customers in the market is still quite small. The reason for the increase in 

residential REC purchasers is unknown, but could be a result of more targeted efforts to market 

RECs to residential consumers in some regions. While most of the REC buyers are residential 

customers, the majority of REC sales on a kilowatt-hour basis are made to nonresidential 

customers due to the much larger purchase sizes.

Table 14. Estimated Cumulative Number of Customers Buying RECs or Green Power 

from Competitive Marketers, 2003-2008

2003 2004 2005 2006 2007 2008

Competitive Markets ~170,000 <140,000 >180,000 ~ 210,000 ~300,000 ~390,000

RECs* <10,000 <10,000 <10,000 ~ 10,000 ~13,000 ~30,000

Total ~180,000 <150,000 ~190,000 ~ 220,000 >310,000 ~425,000

% Change 13% -17% 27% 16% 37% 37%

*Includes only end-use customers purchasing RECs separate from electricity. 

Note: Totals may not add due to rounding. 

In recent years, most of the customer gains in competitive markets resulted from utility/marketer 

partnership programs in the Northeast as well as customers who switched from default service to 

retail green power providers in a few states, most notably Texas. These gains have been 

tempered by losses in some states, where marketers have struggled to provide electricity service 

to consumers amidst adverse market conditions and increasing costs. During 2007, EIA data 
18

show declines in the number of green power customers in Virginia but gains in Texas, Maryland, 

Pennsylvania, and Washington, D.C (see Appendix C). 

REC and Competitive-Market Green Power Sales

An estimated 19.5 billion kWh of renewable energy was sold to retail customers by competitive 

green power and REC marketers in 2008 (Table 15). This figure includes renewable energy from

both pre-existing and new sources. In 2008, about 85% of the REC and green power 

competitive-market retail kilowatt-hour sales were supplied from new renewable energy sources. 

An estimated 3.9 billion kWh were sold as a bundled green power product in competitive 

electricity markets—more than a 20% increase from 2007. The competitive-market sales figure 

includes renewable energy sales through default utility/marketer programs or individual 

utility/marketer partnerships in competitive markets, which amounted to approximately 950

million kWh in 2008, a 35% increase from 2007 (see Figure 5). Retail REC sales increased by 

nearly 50%, reaching 15.6 billion kWh in 2008. Most of the growth in REC-only sales is 

attributable to the nonresidential sector.

Table 15. Retail Sales of Renewable Energy in Competitive Markets and RECs*

(Million kWh), 2004-2008

2004 2005 2006 2007 2008

 Residential 2,140 1,330 1,000 1,800 2,700

 Nonresidential 510 820 710 1,400 1,200

 Subtotal 2,650 2,150 1,720** 3,200 3,900

 % Change 40% -19% -20%** 88%** 22%

 % Residential 81% 62% 59% 56% 69%

 Residential 40 40 110 60 200

 Nonresidential 1,690 3,840 6,700 10,500 15,400

 Subtotal 1,720 3,890 6,810 10,500 15,600

 % Change 160% 126% 75% 55% 49%

 % Residential 2% 1% 2% 1% 1%

Total Sales 4,370 6,040 8,530 13,800 19,500

 % Change 71% 38% 41% 62% 41%

Unbundled RECs***

Competitive Markets

*Totals may not add due to rounding. 

 **2006 are likely underestimated because of data gaps. 

***Includes only RECs sold to end-use customers separate from electricity. 

Table 15 also delineates green power sales by customer segment. In 2008, residential customers 

represented more than two-thirds of green power sales in competitive markets. In contrast, 

nonresidential customers represented nearly all unbundled REC sales. Generally, nonresidential 

customers find REC-only products attractive because of their flexibility and the greater potential 
19

for cost savings because they can be sourced from renewable energy projects in more favorable 

resource locations; also, the electricity does not have to be delivered directly to the customer, 

which lowers transaction costs. On the other hand, residential customers may not be aware that 

RECs are available or may not understand them. As noted above, the slight uptick in residential 

REC purchasers in 2008 may have resulted from more targeted efforts to market RECs to 

residential customers in some regions; however, the actual cause of the increase is not known. 

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.26

In 2008, renewable energy sold in competitive markets or as unbundled RECs represented an 

equivalent renewable energy capacity of nearly 5,800 MW, with almost 4,900 MW of this total 

coming from “new” renewable energy resources (Table 16). This is up from 3,700 MW of 

equivalent capacity and 3,000 MW of new capacity in 2007. Equivalent figures for 2006 are 

2,400 MW and 2,100 MW, respectively. Capacity estimates for earlier years are provided in 

Table 4 and Appendix A. 

Table 16. Renewable Energy Sources Supplying Competitive and REC Markets, 2008

MWh Sales 3,697,000 345,000 2,124,000 23,000 13,293,000 44,000 19,526,000

% of Total Sales 19% 2% 11% 0.12% 68% <1% 100%

Total MW 500 40 610 20 4,590 10 5,770

MW New RE 420 3 130 20 4,270 -- 4,860

Unknown Total

Biomass/ 

Landfill Gas

Geothermal Hydro Solar Wind

Information on new content is unavailable in some instances. 

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

(Appendix B), see http://www.epa.gov/greenpower/. In addition, the Green Power Market Development Group 

promotes the purchase of RECs among its members, see the organization’s Web site at: 

http://www.thegreenpowergroup.org/. 
20

The Voluntary Carbon Offsets Market

Green power markets are affected by other related markets, such as the emerging U.S. market for 

greenhouse gas (GHG) offsets. Because green power and GHG offset markets have converged in 

recent years, this section addresses GHG offsets sourced from renewables. A GHG offset

(sometimes referred to as a carbon offset) is a tradable commodity representing a unit of GHG 

emissions reduction or avoidance—typically, one metric ton of carbon dioxide equivalent 

(CO2e). Corporations and individuals are buying these products to “offset” their own emissions, 

such as those associated with energy used for heating, product manufacturing processes, 

automobile use, and air travel. 

GHG offsets can be derived from a variety of project types that reduce or avoid GHG emissions, 

which use diverse methods for measuring these reductions. Examples of GHG reduction projects 

include renewable electricity generation, energy efficiency measures, methane capture at landfill 

sites, soil carbon sequestration, and forestry projects. Developers of these project types can sell 

GHG offsets to consumers or businesses to help finance their projects. For GHG offsets sourced 

from renewable energy generation projects, the equivalent emissions reduction of replacing 

conventional generation with renewable generation must be calculated. More than 25 companies 

offer offset products derived at least, in part, from renewable energy generation projects.27

Offsets sourced from renewable energy differ from green power in that they are sold in tons of 

CO2e, while RECs and other forms of green power are sold in kilowatt-hours. In addition, 

certification standards for offsets differ from those for renewable energy and not all RECs can be 

converted to offsets. Generally, offsets must demonstrate additionality, meaning that the

emissions reductions are additional to what would have occurred anyway (or under business as 

usual). Retail customers typically purchase green power or RECs equivalent to a portion or all of 

their electricity consumption. In contrast, retail customers buying GHG offsets generally 

purchase tons of CO2e to match their carbon emissions. There is overlap in the sense that many 

green power purchasers are motivated to buy green power for their electricity consumption out of 

concern about climate change and to address their electricity-related GHG emissions. Currently, 

renewable energy could provide either a GHG offset (ton of CO2) or a kilowatt-hour of green 

power—however; there are double-counting concerns if the same kilowatt-hour is sold as both 

an offset and a REC. Certifiers generally do no allow this type of double counting. 

Eight out of approximately 20 GHG offset providers that offer products at least partially sourced

from U.S.-based renewable generation reported 2008 offset sales to NREL. The carbon offsets

sourced from renewables totaled nearly 250,000 metric tons of C02 equivalent, which is 

equivalent to about 340,000 MWh of renewable energy generation.28 

 

27 The Green Power Network tracks GHG offset providers and products that are available nationally and are derived 

at least in part from U.S.-based renewable energy generation projects 28 The EPA’s national average electricity emissions factor for nonbaseload generation (eGRID 2009) was used to 

estimate the equivalent in MWh.
21

Table 17. GHG Offsets Sourced from U.S.-Based Renewable Energy Sources, 2008

Metric Tons 

CO2e

Equivalent 

in MWh

Residential 31,200 43,500

Non Residential 214,700 299,000

Total 245,900 342,500

Several independent certifiers have created standards for verifying emissions GHG reductions to 

ensure that they are real, measurable, and beyond business as usual and any regulatory

requirement. They also establish ownership of the actual emission reductions so that multiple 

parties do not claim the carbon reduction. GHG offset providers responding to the NREL 

questionnaire reported that some, if not all, of their offsets were verified by the following 

organizations: Center for Resource Solutions,

29 Environmental Resources Trust,30 or the Chicago 

Climate Exchange (CCX).

31

Proposed federal or regional cap and trade programs have the potential to impact the ability for 

renewables located within capped regions to provide GHG offsets once emissions caps take 

effect, depending on program design details. Because renewables provide indirect emissions 

reductions by displacing emissions from fossil fuel generators, they may not have a claim to the 

emissions reductions under a cap and trade program, unless provisions such as allowance set 

asides are adopted. The Regional Greenhouse Gas Initiative in the Northeast, the only cap 

currently in effect in the U.S., includes a voluntary renewable energy set aside through which 

states retire CO2 allowances on behalf of voluntary renewable energy purchases, ensuring

emission reductions associated with the renewable generation. 

 29 In February 2008, the Center for Resource Solutions certified its first retail products under Green-e Climate, a 

consumer-protection program requiring verification of GHG reductions based on a project-level certification 

program that ensures the reductions have taken place, are permanent, and come from projects that would not have 

happened under a "business-as-usual" scenario. Sellers must undergo a yearly audit to ensure their supply of offsets 

matches their sales, and comply with Green-e Climate's consumer-disclosure and truth in advertising requirements. 

The Green-e Climate Protocol for Renewable Energy requires that GHG emissions reductions from renewable 

energy must meet all the Green-e Climate verification standards as well as additionality requirements to ensure that 

they are beyond business as usual. The protocol requires that the RECs associated with the renewable energy 

generation certified under Green-e Climate be retired and not resold in the voluntary green power markets or used 

for compliance with renewable energy standards. The generator and/or seller must verify that the attributes are only 

sold once, and not double counted. For more information, see the protocol at http://www.greene.org/docs/climate/Green-e_Climate_Protocol_for_RE.pdf. 30 The Environmental Resource Trust/Winrock International verifies carbon offsets in partnership with the American 

Carbon Registry. The American Carbon Registry allows flexibility for members to choose among methodologies set 

out by the Clean Development Mechanism (CDM) and the Voluntary Carbon Standard (VCS). A carbon offset is 

considered an emissions reduction ton (ERT) if it is real, additional, permanent, and that ownership is incontestable. 

After verification, the Registry assigns each offset a unique serial number. For more information on the ERT 

certification, see http://www.winrock.org/common/files/Solution_Stories/acr_capabilities.pdf. 31 The Chicago Climate Exchange guidelines for carbon offsets sourced from renewable energy generation were 

established in 2006. To qualify, RE systems must have been activated on or after January 1, 2005. Project 

proponents must demonstrate ownership rights associated with the environmental attributes, (i.e. must not have sold 

the RECs, or used them for compliance purposes). Under the verification process, for CCX Offsets to be issued, the 

RECs are surrendered to and retired by CCX. For more information on the CCX guidelines, see 

http://www.chicagoclimatex.com/news/publications/pdf/CCX_Renewable_Offsets.pdf
22

Voluntary Green Power Market Trends and Issues

As the voluntary green power market continues to grow, a few trends and issues have surfaced. 

This section explores the appropriate level of marketing costs for utility green pricing programs, 

highlights trends in REC prices in both the compliance and voluntary markets, and explores the 

future role of the voluntary market as compliance markets expand. 

Program Marketing Expenditures: Finding the Right Balance

In 2008, some market observers raised concerns about optimal levels of spending for marketing 

green pricing programs. As a percentage of program revenues, programs spent a median of 

18.8% on marketing their program in 2008 and 16.6% in 2007, with the smallest utilities (with 

less than 25,000 in their eligible customer base) spending 49% of revenues, significantly more 

than the overall median. Figure 6 shows 2008 marketing and administration expenditures by 

utility size.32

Figure 6. Average program marketing and administration expenditures (2008), by utility size

 

32 Some caveats must be understood with respect to these data. Programs’ data collection methods and proficiency 

tend to be inconsistent. There is no single set of accounting definitions to which programs adhere. Some programs 

do not collect these data at all, and some collect but do not report it to NREL. In addition, there is likely an inherent 

“survivorship” bias, or tendency for programs to under-report data showing poor results or high acquisition costs. 

Several programs either have no budgets or rely on broader utility marketing budgets for some or all of their 

marketing expenditures and/or labor costs. In such cases, these costs are paid for by all ratepayers rather than solely 

by program participants, resulting in a lower reported expenditure. The recent increased scrutiny on these data 

suggests improving and standardizing accounting and collection practices.
23

Budgets for marketing and administration of green pricing programs are a function of several 

factors: the region of the country; the size of the utility service area; the customer base and media 

markets encompassed within that service area; the point or stage in the lifespan of the program;

and certainly, not least, the utility’s commitment to and goals for the program. All of these 

factors vary significantly among programs. 

Conclusions about what might be the optimal level of program expenditures for marketing often 

rest on whether such expenditures are framed as consumer education in the public interest. As in 

many businesses, programs must balance investing in consumer education, expanding program 

participation, keeping participation affordable, and maintaining standards for product quality and 

supporting new renewable energy development. These goals are not mutually exclusive; strong 

marketing has been shown to support robust participation, which can enable a program to 

support more new renewable energy projects. How a program strategy is designed depends on 

what the strategy is meant to accomplish. Some utilities have comprehensive environmental 

goals or goals intended to green their brand. Other utilities aim only to make a renewable option 

available to customers and spend little or nothing on marketing. 

While program experience has shown that marketing expenditures are important for program 

growth, the question of the optimal amount of marketing expenditures has arisen largely in the 

context of product quality, specifically around the perception that participant dollars could be 

better put to use through greater investment in more new renewable capacity than in marketing. 

Yet active marketing need not come at the expense of product quality—spending more to attract 

more participation can instead grow the size of the market and result in more new development. 

Like any new business, some programs tend to spend more on marketing in their “start-up” phase 

(the first two to three years of a new program), during which time the program feels its greatest 

burden to educate customers about the new offering and entice them to enroll. Even those that do 

not spend significantly more on marketing in early years subsequently spend less as a percentage 

of revenues over time, simply because their revenues tend to increase over time. Like any 

business, the start-up phase is a relatively costly investment for which programs sometimes do 

not see a return for several years. 

In the start-up phase of a business—which can be a different length of time for different 

industries—the new business has a disproportionate need to spend money on several cost 

components that tend to lessen in subsequent years. These include the following: 

• Hiring and training staff and call center representatives

• Conducting market research 

• Developing a business plan and designing the program

• Establishing a brand and building product awareness

• Identifying the target market and message

• Building a Web site

• Identifying and purchasing wholesale products

• Developing and creating marketing materials

• Establishing mechanisms for billing and for processing sales.
24

On the other hand, it can become more costly to attract customers in the later years in the life of 

a program, after the “low-hanging fruit”—the customers most inclined to sign up—are already 

enrolled. In this later phase, some programs engage in more expensive marketing tactics, such as 

direct mail or telemarketing. Program managers might do this for a combination of reasons. For 

example, they might conclude that the less expensive bill inserts or bangtails have accomplished 

what they can, they could be limited in the number of bill inserts that their program can use 

because of competition from other internal utility programs, or they might tailor specific 

messages to residential customer segments that have been less inclined to participate. As a result, 

marketing costs could increase again in the later years of a program. 

The question of program marketing expenditures inevitably leads to broader issues of program 

transparency, the value customers are receiving for their premium, and the question of how well 

the expenditures are accomplishing their stated goals. On the question of transparency, the 

Green-e Energy certification program, which has become the leading certification standard for 

green pricing programs, does not require public disclosure of the renewable energy projects 

supported by a green pricing program, or disclosure of the budgets or breakout data on program 

expenditures. However, some consumer advocates have said that a “best practice” standard 

should include project disclosure, contending that consumers have a right to know which projects 

their premiums are supporting. 

To better understand recent concerns about marketing costs, particularly among investor-owned 

utilities, it is useful to view current issues in light of the original impetus for green pricing. The 

first programs were launched in the mid- to late 1990s during the movement toward retail 

electricity restructuring and its concomitant emphasis on customer choice. Green pricing 

programs were by design the first, and they remain the only, non-price-based differentiator for 

electricity commodity. They are the only option for customers to choose electricity not as a 

commodity but as a product reflecting customer values. 

Yet from the outset, customer confusion about the new product made consumer education a 

necessary element to the success of green pricing programs. Such educational efforts, and the 

increased costs associated with them relative to other utility programs, have been supported by 

some regulators as squarely within the public interest. This is primarily because of the product’s 

promise as a solution to environmental and other public concerns, and the notion of the public’s 

interest in having a value-based choice in their energy supply.

Product or Donation: Why has the question of marketing expenditures arisen?

It is unusual for the level of a private, unregulated for-profit company’s marketing expenditures 

to be questioned, although charities may face such questions. One would assume that a company 

has incentive to spend only the amount of money justified by the expected return on that 

expenditure, so that the free market can be trusted because of these built-in incentives. But 

energy is a regulated industry, and regulators are charged with protecting customer value. In 

addition, green pricing programs bear similarities to charitable organizations and may well be 

facing more scrutiny because of those similarities. In fact, some utilities have marketed programs 
25

as charitable contributions which, in some cases, are tax-deductible.

33 However, the industry has 

more typically framed green power conceptually as a “product,” a quantity of renewable energy 

that matches all or part of consumers’ electricity consumption. Of the more than 850 U.S. green 

pricing programs, about 15-20 call themselves “contribution” programs.34

Unlike private businesses, charitable organizations’ value is evaluated in part on how little they 

spend on marketing and administration. The question is asked far less of for-profit companies. 

And, in the case of green pricing programs, if more marketing expenditure results in greater 

demand for renewable energy or in greater program participation, should that reduce the 

importance of the question of how much was spent on marketing? In determining optimal levels 

for programs to spend on marketing, it is helpful to appreciate the ambiguity in the nature of the 

green pricing product and premium. Is the premium a payment for a product or a donation

supporting a cause? Customers are purchasing a product, in that in the vast majority of programs,

they are paying for a specific quantity of renewable energy to match their electricity 

consumption. Yet green pricing programs bear important similarities to charities. The 

comparison of green pricing programs to charities is made for several reasons. Perhaps the most 

important is the similarity in messaging, with its emphasis on doing the right thing, “making a 

difference,” and the legacy message with a call to action for future generations and for the 

environment. Similar to charitable organizations, green pricing programs typically craft “cause 

marketing” messages that resemble a request for a donation in that an appeal is made to make a 

difference or do the right thing. Typical examples of marketing claims and calls to action in 

green pricing marketing materials include the following:

• a...way to support our environment.

• leaving our family a brighter future.

• develop new renewable energy resources.

• make an impact...on the environment.

In addition to the messaging similarities to “cause” marketing, there is a question regarding the 

green power product itself: Because it has no tangible personal benefit or, at the very least, the 

benefit is primarily public, can it be said that those “buying” it are buying a product? The 

similarity to charitable causes is an important one in the context of marketing expenditures, 

because it is only in this similarity that the question has been asked in the first place; companies 

selling products and services are rarely, if ever, scrutinized on this basis. In their 2008 case 

before the Florida Public Service Commission, Green Mountain Energy Company raised the 

applicability of the question, as follows: 

“[A] utility company might contract with a local General Motors dealer to purchase a fleet of trucks. The 

utility pays the dealer the agreed-upon price... After the dealer has covered the cost of purchasing and 

delivering the trucks, any revenue left over from the purchase price belongs to the dealer. Any inquiry 

into the dealer’s advertising, selling or other costs is inappropriate and demonstrates a misunderstanding 

of the legal and economic basis of the relationship between the dealer and FPL.”

 33 For example, NC Greenpower, a program which is offered to utility customers throughout North Carolina, offers 

tax deductions for “contributions” to the green power program. For more information, see 

http://www.ncgreenpower.org/signup/online_contributions.html. 34 For more information, see greenpower.energy.gov. 
26

The green pricing premium could be compared to a donation to public radio, where consumers 

and businesses “buy” the product for their neighbors, not just for themselves; they pay for a 

service they are receiving and for a public good at the same time. On the other hand, because 

green pricing participants are receiving a product tied to specific quantities based on the amount 

of energy they use, the purchase could also be seen as more akin to a product purchase than a 

charitable donation—in these cases, people generally donate money based on what they can 

afford or wish to contribute. 

Energy-based green pricing programs can be distinguished from charities on the basis of the 

specific amount of energy delivered to the grid. When making a charitable contribution, donors

give what they can afford in expectation that the beneficiary will put their contribution to “good 

use.” The efficacy of the charity is judged in part on the portion of the donation spent on the 

“cause.” This ratio is not always known at the time the donation is solicited. In addition, because 

some companies now use renewable energy to claim emissions reductions, it is important to 

understand that such claims are made on the basis of a purchase of renewable energy, as 

distinguished from a donation.

In contrast, an energy-based green pricing program typically offers a firm quantity of renewable 

energy at a firm price. The price, terms, and conditions are disclosed in standardized language in 

most cases and always in the case of Green-e Energy certified programs. For example, when 

programs offer a 100% usage option, if a customer on average uses 1,000 kWh per month and 

the offered green premium is 1.5 cents per kWh, then the consumer can be confident that the 

enrollment will result in 1,000 kWh of renewable energy being added to the grid at a cost of $15 

per month added to their bill. The customer can evaluate whether they perceive the offering to be 

a good value. 

In the final analysis, it is only in considering the hybrid nature of voluntary programs that a 

balanced assessment of “how much is too much” marketing costs can be made. Furthermore, 

there is no clear optimal level of marketing expenditure; rather, appropriate costs may vary by 

type of program, customer base, age of program, and a variety of other factors. 
27

Renewable Energy Certificate Prices

This section provides an overview of wholesale REC prices in voluntary and compliance markets

in recent years 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 a number of factors, including whether the RECs are bought 

to meet compliance obligations or serve voluntary retail consumers, the technology, the vintage

(year in which it was generated), the volume purchased, whether they are eligible for 

certification, and the region in which the generator is located. 

The region from which RECs are sourced is particularly important because often there are 

regional differences in renewable energy resource quality (i.e., wind speed) and electricity prices 

that determine the cost-effectiveness of the renewable generation. In addition, the supply and 

demand of RECs often varies regionally. In regions where there have been shortages of 

renewables to meet RPS requirements, REC prices have reached or come near to levels for 

alternative compliance payment (ACP) of $50-$55/MWh; whereas, in other states or regions,

compliance RECs have sold for less than $5/MWh. Figure 7 shows the wide variation in 

compliance-market REC prices among states for which data are available. 

$0.00

$10.00

$20.00

$30.00

$40.00

$50.00

$60.00

01/01/0602/01/0603/01/0604/01/0605/01/0606/01/0607/01/0608/01/0609/01/0610/01/0611/01/0612/01/0601/01/0702/01/0703/01/0704/01/0705/01/0706/01/0707/01/0708/01/0709/01/0710/01/0711/01/0712/01/0701/01/0802/01/0803/01/0804/01/0805/01/0806/01/0807/01/0808/01/0809/01/0810/01/0811/01/0812/01/0801/01/0902/01/0903/01/0904/01/0905/01/0906/01/09

CT DC DE MA MD NJ PA RI TX

 Sources: Evolution Markets, Spectron Group, Barbose 2009

Figure 7. Compliance market (primary tier) REC prices, 2006 to mid-2009
28

Solar RECs (SRECs) have higher value than RECs from other resource types in both compliance 

and voluntary markets. This is true for a number of reasons: 1) at least 18 state RPS programs 

have specific provisions to encourage solar or distributed generation (DG) (DSIRE 2009e); 2) 

the penalty price for noncompliance is often set higher for solar/DG tiers than for standard RPS 

compliance; and 3) SRECs can be desirable in the voluntary market, where customers may be 

willing to pay more for solar, which costs more than other renewables. Data availability is 

limited, but several price points are indicative of the higher market price for SRECs in 

compliance markets in 2009 (Table 18). Figure 8 compares voluntary solar RECs to generic and 

wind RECs. In the first half of 2008, both voluntary solar RECs (SRECs) sourced from 

anywhere in the nation and those from the Western region ranged from about $7/MWh to 

$10/MWh.

Table 18. 2009 Compliance Market SREC Prices

Range of SREC Prices

New Jersey $665 -$685

Delaware $225 - $300

Maryland $350 

Pennsylvania $275 - $315

Source: Spectron Group 2009

Note: Values represent the midpoint of the bid and offer prices for current-year vintage. 

While compliance RECs generally must be sourced from within some geographic region to be 

eligible for RPS compliance, voluntary RECs can be sourced either regionally or nationally. 

Most utility green pricing programs or marketers selling bundled electricity and REC products 

source their products from local or regional resources, with some exceptions. Buyers of 

nationally sourced RECs are often large corporations that have facilities in multiple locations 

across the country. In voluntary markets, RECs that are sourced locally (within the region) may 

have to compete with RPS demand or be subject to regional resource limitations. Therefore, 

regionally sourced RECs often sell at a premium to nationally sourced RECs, which are often

derived from the most cost-effective renewable resources. As shown in Figure 8, wholesale 

RECs used in voluntary markets have generally traded in the range of $1/MWh to $10/MWh, 

based on available indicative data. 
29

$0.00

$5.00

$10.00

$15.00

$20.00

$25.00

National Wind West Wind National Any Tech National Solar West Solar

Sources: Evolution Markets, Spectron Group, Barbose 2009

Figure 8. Voluntary REC prices, 2006 to mid-2009

Table 19 presents wholesale REC prices for wind and for any renewable energy technology 

located nationally, as well as wind from within the Western Electric Coordinating Council

(WECC). In 2008, prices paid for nationally sourced RECs from any technology ranged from 

about $1.50/MWh to $5.50/MWh; but, in the first half of 2009, these prices declined, ranging 

from about $1/MWh to $2/MWh (see Figure 8). Wind RECs, sourced both nationally and from 

WECC, netted higher prices, on average, than generic RECs sourced from any technology; but 

they also fell in late 2008. Prices differ not only by the technology and the location, but also by 

the vintage. Voluntary RECs sold in a given year can only be Green-e Energy certified if the 

renewable energy with which they are associated is generated in the calendar year in which the 

product is sold, the first three months of the following calendar year, or the last six months of the 

prior calendar year (CRS 2008). Table 19 shows price ranges for different vintages based on bids 

and offers in 2008 (ranges are based on the midpoint between bid and offer prices). Forward 

contracts for 2009 vintage RECs were sold at a slight premium during 2008. 

Table 19. Range of Voluntary REC Prices in 2008 for Different Vintages ($/MWh)

Range Year 2007 2008 2009

National Any Technology $1.5 - $4.7 $1.9 - $5.3 $2.7 - $5.5

National Wind $1.5 - $4.7 $1.9 - $5.7 $2.7 - $6.1

WECC Wind $2.3 - $6.4 $3.8 - $7.9 $6.1 -$8.6

 Source: Spectron Group 2008
30

Regional REC Supply and Demand Balances 

As the geographic coverage and stringency of state renewable portfolio standards (RPS) 

increases, and in light of the debate over a federal RPS, implementers have asked whether 

supplies will be adequate to meet these existing policies as well as demand from voluntary 

purchasers. Supply shortages have occurred in some regions, which has increased prices for 

RECs and limited supplies available to voluntary markets in a few instances. This has caused

some concern that increased demand for renewables resulting from RPS policies will outstrip 

supplies and increase prices for RECs in coming years. 

In an attempt to shed some light on these questions, a recent NREL analysis (Bird et al. 2009) 

examined the balance between the demand and supply of new U.S. renewable electricity on a 

regional basis through 2015. The analysis relied on estimates of renewable energy supplies 

compared to the demand for renewable energy generation necessary to meet existing state 

renewable portfolio standard (RPS) policies in 28 states as well as demand by consumers who 

voluntarily purchase renewable energy.35 Note that the analysis did not consider the impacts of a 

potential federal RPS, only policies already in place. Two supply scenarios were examined: 1) a 

business-as-usual (BAU) scenario based on current growth rates in renewable energy supply in 

each region, and 2) a market-based scenario that differs only in an assumed higher overall level 

of wind energy development nationally (based on estimates from BTM Consult and referred to as 

“high wind case”). 

The analysis found an overall national surplus of renewable energy generation to meet existing 

RPS policy targets and voluntary market demand over the study period. However, based on the 

assumptions in the analysis, some regional shortages were projected, as well as regions with 

excess supplies. Figure 9 compares the two supply scenarios to renewable energy demand from 

RPS policies and voluntary markets in each of the regions considered in this analysis for 2015. It 

is important to note that the analysis did not take into account the effect of the global financial 

crisis, because of the uncertainty of the impacts. 

Based on the assumptions in the analysis, deficits were projected for New England, New York, 

and the Mid-Atlantic areas, with notable surpluses in the Midwest, the Heartland, Texas, and the 

West. The BAU scenario, based on an extrapolation of recent development trends, found an 

internal shortfall for California; while, under the high wind energy scenario, California had 

excess generation except for one year (2010). The analysis did not assume trading among the 

regions specified in the analysis; however, in some cases, such trading may be feasible to the 

extent that it is not limited by transmission access or state RPS renewable energy certificate 

(REC) trading rules. For example, shortages in California—which is treated as an independent 

region in the analysis—could possibly be offset by surplus supply projected elsewhere in the 

West to the extent it can meet California’s deliverability requirements.

 35 However, the analysis did not address demand by utilities that may procure cost-effective renewables through an 

integrated resource planning process or otherwise.
31

0 20,000 40,000 60,000 80,000 100,000

Midwest

New England

New York

Mid Atlantic

Heartland

Southeast

California

West

Texas

Generation (GWh) 2015

Demand BAU Supply High Wind Supply

Figure 9. Snapshot of regional demand and supply under the two cases 

in 2015 (GWh)

In addition to interregional transfers where transmission is available, shortfalls could be 

addressed through price signals that may accelerate development of renewable energy resources 

that are currently uneconomic. This is particularly true in areas that have no or few market 

barriers. In areas with market barriers or transmission constraints, removing barriers to 

development, adding new transmission, and expanding interregional REC trading could alleviate 

potential regional shortfalls and enable states to access least-cost renewables. Key uncertainties 

in the analysis include the impact of the global financial crisis, potential changes in incentives or 

policies, the ability for renewable energy to access transmission, as well as the ability to develop 

offshore wind in the East.36

If renewable electricity shortages develop as projected in some regions by 2015, it is likely that REC 

prices will increase in those regions. Higher prices could dampen voluntary demand in affected 

regions, and RPS demand might even outbid some existing regional voluntary demand. However, 

prices for nationally sourced RECs would not necessarily be affected by regional shortages—as 

long as a national shortage does not develop, which has been the case in the recent past. 

 36While the pace of development in coming years will depend on the ability of the federal government and the 

financial industry to address the financial crisis and increase the availability of debt for project financing, the 

estimates presented in the analysis did not account for potential impacts of the crisis, because they are highly 

uncertain.
32

Conclusions and Observations

The green power market continues to exhibit strong growth and provide an important demanddriven stimulus for renewable energy development. Green power markets provide an additional 

revenue stream for renewable energy projects, and raise consumer awareness of the benefits of 

renewable energy. Based on this review, we have identified the following market trends:

• In 2008, total retail sales of renewable energy in voluntary-purchase markets exceeded 24 

billion kWh, representing a capacity equivalent of 7,300 MW of renewable energy, 

including 6,300 MW from “new” renewable energy sources. 

• Wind energy provided 71% of total green power sales, followed by biomass energy 

sources including landfill gas (17%), hydropower (9%), geothermal (2%), solar (<1%), 

with the remainder unknown (1%). 

• Total market sales increased by nearly 35% in 2008, dominated by REC sales to 

nonresidential consumers, which increased by about 50%. Commercial and institutional 

REC markets now represent nearly two-thirds of green power market sales, surpassing 

sales in competitive electricity markets and utility green pricing programs.

• Overall, the total number of customers purchasing green power increased by nearly 15%

in 2008, a slower rate than in previous years, with gains primarily in competitive and 

REC markets. Utility green pricing program participants remained essentially flat in 

aggregate, with some programs reporting customer losses, presumably due to the 

economic downturn. 

• Utility green pricing programs in regulated electricity markets continued to grow on a 

sales basis, but at a slower rate than in previous years, with sales increasing by about 10% 

in 2008. A relatively small number of utility programs continue to dominate sales and 

customer numbers. In fact, the termination of one large program had a significant impact 

on market growth. Some programs experienced growth in sales even amidst customer 

losses, as a result of increased sales to commercial and institutional customers. 

• Utility premiums for green pricing have continued to fall, which is attributed to a 

combination of higher prices of conventional generation fuels and lower renewable 

resource costs; however, these trends have become less clear with the economic declines 

in late 2008. 

• In 2008, nearly 250,000 tons of CO2e avoided from renewable energy facilities were 

marketed as offsets. This is the equivalent of about 340,000 MWh of renewable energy 

generation. Offset products sourced from renewables and sold to U.S. consumers are 

being certified by a number of organizations including CCX, Green-e Climate, and ERT. 

• In 2008, sales to nonresidential customers continued to outpace those to residential 

customers, bringing the fraction of nonresidential sales to more than three-quarters of all 

green power sales on a kilowatt-hour basis. The growing dominance of nonresidential 

sales is a departure from the early history of green power markets when most products 

and programs were oriented toward residential customers.
33

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34

Center for Resource Solutions (CRS) (2007). 2006 Green-e Verification Report, San Francisco, 

California, November. http://www.green-e.org/publications.shtml

Center for Resource Solutions (CRS) (2008). National Standard Version 1.6. San Fransisco, CA, 

December. http://www.green-e.org/docs/energy/Appendix%20D_Greene%20Energy%20National%20Standard.pdf

Friedman, B.; Bird, L.; Barbose, G. (2008). Considerations for Emerging Markets for Energy 

Savings Certificates, NREL/TP-670-44072, Golden, CO: National Renewable Energy Laboratory, 

October. http://www.nrel.gov/docs/fy09osti/44072.pdf

Holt, E.A.; Holt, M. (2004). Green Pricing Resource Guide (2nd Edition), Ed Holt & Associates, 

Inc., Harpswell, Maine. Prepared for the American Wind Energy Association, Washington DC, 

September. http://www.awea.org/greenpower/greenPricingResourceGuide040726.pdf

Holt, E. and R. Wiser, (2007). The Treatment of Renewable Energy Certificates, Emissions 

Allowances, and Green Power Programs in State Renewables Portfolio Standards. Report 

prepared for Lawrence Berkeley National Laboratory, Berkeley, California, April. LBNL-62574. 

http://eetd.lbl.gov/ea/ems/reports/62574.pdf

Karelas, A. (2009). Center for Resource Solutions, San Francisco, California, personal 

communication, July 5-July 22.

National Renewable Energy Laboratory (NREL). (2008). “NREL Highlights Leading Utility 

Green Power Programs.” News release. Accessed April 28, 2008. 

http://www.eere.energy.gov/greenpower/resources/tables/pdfs/0408_topten_pr.pdf

Swezey, B.; Bird, L. (2001). Utility Green Pricing Programs: What Defines Success? NREL/TP620-29831. Golden, CO: National Renewable Energy Laboratory, August.

http://www.eere.energy.gov/greenpower/29831.pdf

Swezey, B.; Bird, L. (2000). Green Power Marketing in the United States: A Status Report (5th

Edition), NREL/TP-620-28738. Golden, CO: National Renewable Energy Laboratory, August.

http://www.eere.energy.gov/greenpower/resources/pdfs/28738.pdf

Swezey, B.; Bird, L. (1999). Information Brief on Green Power Marketing, 4th Edition.

NREL/TP-620-26901. Golden: CO: National Renewable Energy Laboratory, August.

http://www.eere.energy.gov/greenpower/resources/pdfs/26901.pdf

U.S. Energy Information Administration (EIA) (2008). Green Pricing and Net Metering

Programs, 2006. July. 

http://www.eia.doe.gov/cneaf/solar.renewables/page/greenprice/green_pricing.html Accessed 

August 15, 2008.

U.S. Environmental Protection Agency (EPA) (2008). EPA Green Power Partnership. “National 

Top 25: as of July 8, 2008.” http://www.epa.gov/greenpower/toplists/top25.htm Accessed 

August 15, 2008.
35

Appendix A. Estimates of New Renewable Energy Capacity 

Serving Green Power Markets, 2000-2004 

Prior to 2005, estimates of the capacity serving green power markets were estimated based on 

renewable energy projects used to serve green pricing programs rather than derived from 

renewable energy sales. Therefore, the 2005 and more recent capacity estimates are not directly 

comparable to capacity estimates from previous years. However, the two approaches yield 

relatively consistent results.

Bird and Swezey (2005b) provide details on the derivation of capacity estimates for 2004 and 

earlier. Table A-1 presents estimates of the cumulative new renewable energy capacity serving 

voluntary markets from 2000 to 2004. A brief description of the methodology is included below. 

Table A-1. Estimated Cumulative New Renewable Energy Capacity Supplying Green Power 

Markets, 2000-2004* (Megawatts)

Market 2000 2001 2002 2003 2004

Utility Green Pricing 77 221 279 510 706

Competitive Markets/RECs 90 542 695 1,126 1,528

Total** 167 764 974 1,636 2,233

*Data not directly comparable with Table 4. 

 **Totals may not add due to rounding. 

 Source: Bird and Swezey (2005b). 

The estimates of capacity serving green power markets for 2004 and earlier focus on new

renewable resources used to serve green power customers. New renewable resources are defined 

as projects or portions of projects built specifically to serve green power customers, or recently 

constructed projects that are used to supply green power customers and meet the regional Greene Energy National Standard requirement to have come online on after January 1, 1997. The 

estimates do not include pre-existing renewable energy projects used for green power supply, or 

capacity used to meet state RPS requirements or other renewable energy mandates. 

These estimates generally include the entire capacity of a given renewable energy project, 

regardless of whether the output has been fully subscribed by green power buyers (i.e., if a utility 

or developer completed a project before the entire output was sold to prospective customers). 

Therefore, the estimates may include some capacity for which a green power buyer was not yet 

secured. However, in cases where a portion of a project is used to meet a renewable energy 

mandate, only the remainder of the project is counted. 
36

Appendix B. Leading Purchasers in the EPA Green Power 

Partnership 

Table B-1. Top 25 Purchasers in the EPA Green Power Partnership Program, July 7, 2009 

Ranking Company

Annual Green 

Power Usage 

(kWh)

GP % of 

Total 

Electricity 

Use

Resource Type

1 Intel Corporation 1,301,300,000 48% Biogas, Biomass, Geothermal, 

Small-hydro, Solar, Wind

2 PepsiCo 1,226,403,121 100% Various

3 Whole Foods Market 790,459,000 105% Solar, Wind

4 Kohl's Department Stores 600,990,000 50% Biogas, Biomass, Small-hydro, 

Solar, Wind

5 Dell Inc. 553,708,000 158% Biogas, Solar, Wind

6 City of Houston, TX 438,000,000 34% Wind

7 U.S. Air Force 426,274,291 5% Biogas, Biomass, Solar, Wind

8 The Pepsi Bottling Group 

Inc. 426,239,848 100% Various

9 Cisco Systems Inc. 400,996,000 46% Wind

10 Commonwealth of 

Pennsylvania 400,000,000 40% Biomass, Wind

11 Johnson & Johnson 386,455,711 34% Biogas, Biomass, Small-hydro, 

Solar, Wind

12 City of Dallas, TX 333,659,840 40% Wind

13 HSBC North America 300,000,000 93% Wind

14 U.S. Environmental 

Protection Agency 285,000,000 100% Biogas, Biomass, Geothermal, Wind

15

Wal-Mart Stores, Inc/ 

California & Texas 

Facilities

243,328,000 8% Solar, Wind

16 City of Chicago, IL 214,635,000 20% Biomass, Wind

17 Starbucks 211,291,000 20% Wind

18 Kimberly-Clark 

Corporation 192,730,000 7% Biomass

19 University of 

Pennsylvania 192,727,000 46% Wind

20 U.S. Department of 

Energy 188,599,600 4% Various

21 DuPont Company 180,075,000 4% Biomass, Solar, Wind

22 Wells Fargo & Company 175,000,000 14% Wind

23 Los Angeles County 

Sanitation Districts 171,144,000 54% Biogas

24 Deutsch Bank AG 160,000,000 97% Wind

25 PepsiAmericas Inc. 157,128,393 100% Various

Source: http://www.epa.gov/grnpower/toplists/top50.htm
37

Appendix C. Estimated U.S. Green Pricing Customers by State 

and Customer Class, 2006 and 2007

Table C-1. Estimated U.S. Green Pricing Customers by State and Customer Class, 2006 and 2007

2006

Residential Non-Residential Total Total

 Alabama 9 580 5 585 163

 Alaska 1 520 10 530 356

 Arizona 5 9,125 160 9,285 1,933

 Arkansas 0 0 0 0 0

 California 11 56,380 2,296 58,676 47,527

 Colorado 23 55,635 1,866 57,501 48,093

 Connecticut 3 90 6 96 0

 Delaware 9 7,322 1,592 8,914 2,568

 District of Columbia 3 1,351 3,503 4,854 3,716

 Florida 6 37,536 297 37,833 29,301

 Georgia 19 8,135 173 8,308 5,983

 Hawaii 3 4,698 40 4,738 4,466

 Idaho 6 4,669 148 4,817 4,130

 Illinois 8 3,859 33 3,892 2,770

 Indiana 14 4,244 55 4,299 2,039

 Iowa 45 8,385 808 9,193 8,562

 Kansas 1 1 0 1 0

 Kentucky 13 1,322 16 1,338 889

 Louisiana 0 0 0 0 0

 Maine 2 2,266 228 2,494 2,146

 Maryland 4 40,058 15,896 55,954 37,048

 Massachusetts 5 5,882 273 6,155 5,655

 Michigan 8 13,002 194 13,196 7,992

 Minnesota 106 43,428 606 44,034 32,342

 Mississippi 1 3 0 3 3

 Missouri 17 1,417 22 1,439 459

 Montana 13 974 21 995 460

 Nebraska 5 6,831 60 6,891 4,887

 Nevada 3 513 1 514 379

 New Hampshire 1 0 1 1 0

 New Jersey 3 146 295 441 363

 New Mexico 13 19,339 1,934 21,273 15,577

 New York 10 20,142 1,715 21,857 22,431

 North Carolina 22 11,992 394 12,386 9,480

 North Dakota 10 5,065 21 5,086 5,846

 Ohio 14 1,784 5 1,789 252

 Oklahoma 10 10,645 642 11,287 11,292

 Oregon 17 97,400 3,195 100,595 80,733

Participating Customers

2007

Electric 

Industry 

Participants 

2007 a State
38

2006

Residential Non-Residential Total Total

 Pennsylvania 4 38,301 798 39,099 37,355

 Rhode Island 2 4,776 111 4,887 4,516

 South Carolina 14 4,362 404 4,766 3,535

 South Dakota 7 615 17 632 640

 Tennessee 0 0 0 0 0

 Texas 18 125,849 16,485 142,334 100,950

 Utah 6 22,873 533 23,406 20,188

 Vermont 2 4,281 236 4,517 4,537

 Virginia 2 1,304 2 1,306 2,678

 Washington 25 42,949 936 43,885 35,986

 West Virginia 0 0 0 0 0

 Wisconsin 60 34,252 2,092 36,344 31,335

 Wyoming 8 9,090 4,135 13,225 3,606

Total 591 775,398 62,260 835,651 645,167

State

Electric 

Industry 

Participants 

2007 a

Participating Customers

2007

a Includes entities with green pricing programs in more than one state. 

Note: Nonresidential may include some customers for whom no customer class is specified. Blank cells indicate no data was 

reported for the state or the number of customers in a class was zero. Totals may not sum due to rounding. 

Source: Energy Information Administration, Green Pricing and Net Metering Programs, 2007. April 2009.

http://www.eia.doe.gov/cneaf/solar.renewables/page/greenprice/table5_1.html

Table C-2. Estimated U.S. Green Pricing Customers by Customer Class, 2002-2007

Year

Electric 

Industry 

Participants

Participating Customers

Customer Class

Residential Total**

Nonresidential*

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

2006 484 609,213 35,954 645,167

2007 591 775,398 62,260 835,651

*Note: Nonresidential may include some customers for whom no customer class is specified. 

**Totals may not sum due to rounding. 

Source: Energy Information Administration, Green Pricing and Net Metering Programs, 2006. 

July 2009. http://www.eia.doe.gov/cneaf/solar.renewables/page/greenprice/table4_h1.pdf and 

Green Pricing and Net Metering Programs, 2007. April 2009.

http://www.eia.doe.gov/cneaf/solar.renewables/page/greenprice/table5_1.html
39

Appendix D. Utilities Offering Green Pricing Programs in 

Regulated Markets, 2008

Table D-1. Utilities Offering Green Pricing Programs in Regulated Markets, 2008

Investor-Owned Utilities

AEP Appalachian Power

AEP Ohio

Alabama Power Company

Alliant Energy

AmerenUE

Arizona Public Service

Avista Utilities

Central Vermont Public Service

Cheyenne Light, Fuel and Power Company

Connecticut Light and Power

Consumers Energy

Dayton Power and Light

Dominion North Carolina Power

Dominion Virginia Power

DTE Energy

Duke Energy

El Paso Electric Company

Entergy Gulf States

E.ON U.S.

FirstEnergy

Georgia Power

Green Mountain Power

Gulf Power Company

Hawaiian Electric Company

Idaho Power Company

Indianapolis Power & Light Company

Kansas City Power & Light

Kentucky Power Co.

Kentucky Utilities Company

Louisville Gas and Electric Company

Madison Gas and Electric

MidAmerican Energy

Minnesota Power

NSTAR Electric

Nevada Power

Nevada Power

NorthWestern Energy

OG&E Electric Services

Otter Tail Power Company

PacifiCorp

Portland General Electric Company

Progress Energy

Public Service Company of New Mexico

Puget Sound Energy

SCE&G

Savannah Electric

Tampa Electric Company

Tucson Electric Power Company

UniSource Energy Services

United Illuminating

Upper Peninsula Power Company

Vectren Energy Delivery of Indiana

We Energies

Wisconsin Public Service Corporation

Xcel Energy

Electric Cooperatives

Alabama Electric Cooperative

Associated Electric Cooperative Inc.

Bandera Electric Cooperative

Basin Electric Power Cooperative

Boone Electric Cooperative

Buckeye Power

Central Electric Cooperative

Central Iowa Power Cooperative

Connexus Energy

Corn Belt Power Cooperatives

Dairyland Power Cooperative

Dakota Electric Association

Delaware Electric Cooperative

Deseret Power

Deseret Power/Mt. Wheeler Power Cooperative

East Kentucky Power Cooperative

Electric Cooperatives of Arkansas

Farmers Electric Cooperative

Flathead Electric Cooperative

Georgia Electric Membership Corporation

Golden Valley Electric Association

Great River Energy

Gunnison County Electric Association

Holy Cross Energy

Hoosier Energy

Intermountain Rural Electric Association

KAMO Electric Cooperative

Kauai Island Utility Cooperative (KIUC)

La Plata Electric Association

Lower Colorado River Authority

Lower Valley Energy

Midstate Electric Cooperative

Minnkota Power Cooperative

New-Mac Electric Cooperative

Orcas Power & Light

Oregon Trail Electric Cooperative

Palmetto Electric Cooperative

Park Electric Cooperative

Pedernales Electric Cooperative

Peninsula Light Company

PNGC Power

Prairie Power (formerly CCS/Soyland)

Southern Montana Electric G&T Cooperative

Tri-State Generation and Transmission 

Association

Vigilante Electric Cooperative

Wabash Valley Power Association

Western Farmers Electric Cooperative

Yampa Valley Electric Association

Federal

Municipal/Public Utilities

City of Alameda

American Municipal Power-Ohio

Anaheim Public Utilities

City of Ashland

Austin Energy

Austin Utilities (MN)

Benton County Public Utility District

City of Bowling Green

Braintree Electric Light Department

Burbank Water and Power

CPS Energy (San Antonio)

Cedar Falls Utilities

Central Minnesota Municipal Power Agency

Chelan County Public Utility District

Clallam County PUD

Clark Public Utilities

College Station Utilities (TX)

Colorado Springs Utilities

Columbia River PUD

Concord Municipal Light Plant

Cowlitz PUD

Edmond Electric

City of Eldridge (IA)

ElectriCities

Emerald People's Utility District

Estes Park Light and Power

Eugene Water & Electric Board

Fort Collins Utilities

Gainesville Regional Utilities

Grant County PUD

Grays Harbor PUD

Heartland Consumers Power District

Iowa Association of Municipal Utilities

Keys Energy Services

Lakeland Electric

Lansing Board of Water and Light

Lenox Municipal Utilities

Lewis County PUD

Lincoln Electric System

Lodi Utilities

Longmont Power & Communications

Los Alamos County (NM)

Los Angeles Department of Water and 

Power

Loveland Water & Power

Mason County PUD No. 3

Missouri Joint Municipal Electric Utility

Missouri River Energy Services

Moorhead Public Service

Muscatine Power and Water

City of Naperville

City of New Smyrna Beach

Northern Wasco County PUD

Oklahoma Municipal Power Authority

Omaha Public Power District

Owatonna Public Utilities

Pacific County PUD

City of Palo Alto Utilities

Pasadena Water & Power

Platte River Power Authority

Rochester Public Utilities (MN)

Roseville Electric

Sacramento Municipal Utility District

Salt River Project

San Francisco Public Utilities Commission

Santee Cooper

Seattle City Light

Consumer Protection 

Federal Trade Commission

Green Pricing Accreditation

Low Impact Hydro Institute

Federal

Tennessee Valley Authority
40

Table D-2. Utility/Marketer Green Power Programs in Restructured Electricity 

Markets, 2008

Atlantic City Electric

Consumers Energy 

Connecticut Light & Power

JP&L

Kennebunk Light and Power District

Long Island Power Authority 

National Grid (Massachusetts Electric, Nantucket 

 Electric, Narragansett Electric, Niagara Mohawk) 

NYSEG

Rochester Gas and Electric

Rockland Electric

PECO Energy

PSE&G

United Illuminating
41

Appendix E. Links to Utility Green Pricing Programs,

and REC and Competitive-Market Green Power Offerings

Table of Utility Green Pricing Programs by State:

http://www.eere.energy.gov/greenpower/markets/pricing.shtml?page=1

Renewable Energy Certificate Retail Products:

http://www.eere.energy.gov/greenpower/markets/certificates.shtml?page=1

Retail Green Power Product Offerings in States with Retail Competition: 

http://www.eere.energy.gov/greenpower/markets/marketing.shtml?page=1
42

Appendix F. Top Ten Utility Green Pricing Programs

Table F-1. Green Pricing Program Renewable Energy Sales

(as of December 2008)

Rank Utility Resources Used

Sales

(kWh/year)

Sales

(aMW)a

1 Austin Energy Wind, landfill gas 723,824,901 82.6

2 Portland General Electric b Geothermal, wind 672,469,949 76.8

3 PacifiCorp cde Wind, biomass, landfill 

gas, solar 492,892,222 56.3

4 Xcel Energy ef Wind 362,040,082 41.3

5 Sacramento Municipal Utility District e Wind, solar, biomass, 

landfill gas, hydro 325,275,628 37.1

6 Puget Sound Energy e Wind, solar, biomass, 

landfill gas, hydro 291,166,600 33.2

7 Public Service Company of New Mexico Wind 176,497,697 20.1

8 We Energies e Wind, landfill gas, solar 176,242,630 20.1

9 National Grid gh Biomass, wind, small 

hydro, solar 174,612,444 19.9

10 PECO i Wind 173,375,000 19.8

a An "average megawatt" (aMW) is a measure of continuous capacity equivalent (i.e., operating at a 100% capacity factor). 

b Marketed in partnership with Green Mountain Energy Company. For Portland General Electric, some products marketed in 

partnership with Green Mountain Energy Company. 

c Includes Pacific Power and Rocky Mountain Power. 

d Some Oregon products marketed in partnership with 3Degrees Group Inc. 

e Product is Green-e Energy certified. For Xcel Energy, the Colorado and Minnesota Windsource products are Green-e Energy

certified. 

f Includes Northern States Power, Public Service Company of Colorado, and Southwestern Public Service. 

g Includes Niagara Mohawk, Massachusetts Electric, Narragansett Electric, and Nantucket Electric. 

h Marketed in partnership with Community Energy Inc., EnviroGen, Green Mountain Energy Company, Mass Energy, People's Power 

& Light, and Sterling Planet. 

i Marketed in partnership with Community Energy Inc.
43

Table F-2. Total Number of Customer Participants

(as of December 2008)

Rank Utility Program(s) Participants

1 Xcel Energy a Windsource b

Renewable Energy Trust 71,571

2 Portland General Electric cg Clean Wind

Green Source 69,258

3 PacifiCorp de

Blue Sky Block b

Blue Sky Usage b

 

Blue Sky Habitat

67,252

4 Sacramento Municipal Utility District Greenergy b 45,992

5 PECO f PECO WIND 36,300

6 National Grid hi GreenUp 23,668

7 Energy East (NYSEG/RGE) f Catch the Wind 22,210

8 Puget Sound Energy Green Power Program b 21,509

9 Los Angeles Department of Water & Power Green Power for

a Green LA 21,113

10 We Energies Energy for Tomorrow b 19,615

a Includes Northern States Power, Public Service Company of Colorado, and Southwestern Public Service. 

b Product is Green-e Energy certified. For Xcel Energy, the Colorado and Minnesota Windsource products are Green-e

Energy certified. 

c Some products marketed in partnership with Green Mountain Energy Company. 

d Includes Pacific Power and Rocky Mountain Power. 

e Some Oregon products marketed in partnership with 3Degrees Group Inc. 

f Marketed in partnership with Community Energy Inc. 

g Marketed in partnership with Green Mountain Energy Company. 

h Includes Niagara Mohawk, Massachusetts Electric, Narragansett Electric, and Nantucket Electric. 

i Marketed in partnership with Community Energy, EnviroGen, Green Mountain Energy Company, Mass Energy, People's 

Power & Light, and Sterling Planet.
44

Table F-3. Customer Participation Rate

(as of December 2008)

Rank Utility

Customer

Participation 

Rate Program(s)

Program

Start 

Year

1 City of Palo Alto Utilities ab 21.0% Palo Alto Green 2003

2 Lenox Municipal Utilities c 10.5% Green City Energy 2003

3 Portland General Electric d 9.7%

Clean Wind

Green Source

Renewable Future

2002

4 Madison Gas and Electric Company 9.6% Green Power Tomorrow 1999

5 Silicon Valley Power ab 8.4% Santa Clara Green Power 2004

6 Sacramento Municipal Utility Districtb 7.8% Greenergy 1997

7 City of Naperville Public Utilities e 7.8% Renewable Energy Program 2005

8 Pacific Power – (Oregon only) ab 6.2%

Blue Sky Block

Blue Sky Usage

Blue Sky Habitat

2002

9 River Falls Municipal Utilities f 5.3% Renewable Energy Program 2001

10 Pacific Power ab 5.2%

Blue Sky Block

Blue Sky Usage

Blue Sky Habitat

2002

a Marketed in partnership with 3Degrees Group Inc.

b

Product is Green-e Energy certified (www.green-e.org).

c

Program offered in association with the Iowa Association of Municipal Utilities.

d Some products marketed in partnership with Green Mountain Energy Company.

e

Marketed in partnership with Community Energy Inc.

f

Power supplied by Wisconsin Public Power Inc. 
45

Table F-4. Green Power Sales as a Percentage of Total Retail Electricity Sales (in kWh)

(as of December 2008)

Rank Utility Program Name % of Load

1 Edmond Electric a Pure & Simple 6.4%

2 Austin Energy GreenChoice 6.0%

3 River Falls Municipal Utilities b Renewable Energy 

Program 5.8%

4 City of Palo Alto Utilities ce PaloAltoGreen 5.7%

5 Portland General Electric d

Clean Wind

Green Source

Renewable Future

3.9%

6 Madison Gas and Electric Company Green Power Tomorrow 3.8%

7 Pacific Power – (Oregon only) ce Blue Sky Usage 

Blue Sky Habitat 3.3%

8 Sacramento Municipal Utility District e Greenergy 3.0%

9 Fort Collins Utilities e,f Green Energy Program 2.6%

10 Emerald People's Utility District EPUD Renewables 2.2%

a Power supplied by Oklahoma Municipal Power Authority. 

b Power supplied by Wisconsin Public Power Inc.

c Marketed in partnership with 3Degrees Group Inc.

d

Marketed in partnership with Green Mountain Energy Company.

e Product is Green-e Energy certified (www.green-e.org). 

f

Power supplied by Platte River Power Authority
46

Table F-5. Price Premium Charged for New, Customer-Driven Renewable Powera

(as of December 2008)

Rank Utility Resources Used

Premium

(¢/kWh)

1 OG&E Electric Services b Wind -1.01

2 Edmond Electric bc Wind -0.94

3 Indianapolis Power and Light Wind, landfill gas 0.07

4 Avista Utilities Wind, landfill gas, biomass 0.33

5 Park Electric Cooperative Wind 0.44

6 Austin Energy be Wind, landfill gas 0.69

7 PacifiCorp dg Wind, biomass, landfill gas, solar 0.78

8 Emerald People's Utility District Wind 0.80

8 Basin Electric Power Cooperative h Wind 0.80

8 Clallam County Public Utility District b Landfill gas 0.80

10 Xcel Energy (Minnesota) bdf Wind 0.91

a Includes only programs that have installed or announced firm plans to install or purchase power from 100% new renewable 

resources. b Premium is variable; customers in these programs are exempt or otherwise protected from changes in utility fuel charges.

c Power supplied by Oklahoma Municipal Power Authority. 

d Product is Green-e Energy certified (www.green-e.org).

e The price for new customers enrolling in the program (fifth batch of renewable energy capacity). 

f Net premium of the Minnesota Windsource program. 

g Pacific Power Blue Sky Usage and Blue Sky Habitat products; only available in Oregon. Product marketed in partnership with 3Degrees Group Inc. 

h A number of Basin Electric Power Cooperatives offer green power at a premium of 0.8¢/kWh.
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2. REPORT TYPE

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4. TITLE AND SUBTITLE

Green Power Marketing in the United States: A Status Report 

(2008 Data) 

5a. CONTRACT NUMBER

DE-AC36-08-GO28308

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

L. Bird, C. Kreycik, and B. Friedman

5d. PROJECT NUMBER

NREL/TP-6A2-46581

5e. TASK NUMBER

SAO9.3004

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

National Renewable Energy Laboratory

1617 Cole Blvd.

Golden, CO 80401-3393

8. PERFORMING ORGANIZATION

REPORT NUMBER

NREL/TP-6A2-46581

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S)

NREL

11. SPONSORING/MONITORING

AGENCY REPORT NUMBER

12. DISTRIBUTION AVAILABILITY STATEMENT

National Technical Information Service

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13. SUPPLEMENTARY NOTES

14. ABSTRACT (Maximum 200 Words)

Voluntary consumer decisions to buy electricity supplied from renewable energy sources represent a powerful 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, both from 

traditional utilities and from renewable energy marketers operating in states that have introduced competition into their 

retail electricity markets or offering renewable energy certificates (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. This report documents green power marketing 

activities and trends in the United States including utility green pricing programs offered in regulated electricity markets; 

green power marketing activity in competitive electricity markets, as well as green power sold to voluntary purchasers in 

the form of RECs; and renewable energy sold as greenhouse gas offsets in the United States. These sections are 

followed by a discussion of key market trends and issues. The final section offers conclusions and observations. 

15. SUBJECT TERMS

NREL; Lori Bird; Claire Kreycik; Barry Friedman; renewable energy certificates; RECs; energy consumers; electricity; 

green power marketing; green pricing; renewable energy; electricity markets; utilities; greenhouse gas offsets

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