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Automaker BMW pipes methane from a local landfill site to serve the electrical and thermal needs of its manufacturing facility in South Carolina Photo: BMW

In the US, the use of on-site renewable energy generation is taking off in a big way – partly due to encouragement by the Environmental Protection Agency operating its Green Power Partnership. Now, the top 20 partners combined are generating more than 700 GWh of renewable energy on-site each year.

For many organizations, electricity usage is the primary source of their greenhouse gas emissions. To dramatically reduce these emissions and fight climate change, a growing number of these organizations are switching to green power. Since 2001, the US Environmental Protection Agency (EPA) through the Green Power Partnership has been working with US businesses and organizations to help them make this switch.

EPA has seen a significant increase in partner organizations that are choosing to invest in on-site green power generation to meet desired energy and carbon reduction goals. On-site green power is produced from a subset of renewable electricity resources, including solar, wind, geothermal and low-impact hydropower.

By producing green power at its facility, a host organization captures a number of benefits. On-site green power generates less pollution than conventional fossil fuel power. On-site green power also allows the host to enjoy stable electricity costs and the ability to make a visible demonstration of environmental stewardship. On-site generation also provides economic and social benefits, and additional on-site green power generation expands the nation’s renewable electricity portfolio while reducing the country’s reliance on a centralized energy infrastructure.


To increase the use of green power among commercial and industrial electricity users, EPA launched the Green Power Partnership in 2001. Since then, EPA has worked with hundreds of businesses and organizations to help them procure green power by offering expert advice, technical support, tools and resources.

Today, more than 1100 organizations are Green Power Partners, including Fortune 500 companies, manufacturers, retailers, trade associations, colleges and universities, and local, state and federal government agencies.

Overall, the partners are using more than 16 TWh of green power annually, equivalent to the carbon dioxide emissions from electricity use of more than 1.6 million American homes.


The partnership is open to all organizations operating within the United States, except for sellers, suppliers or marketers of green power. To qualify, an organization must purchase and/or produce a minimum percentage of green power that corresponds to its baseload electricity use (see Table 1). An international organization with facilities in the US may join provided that it counts only US-based facilities using green power toward meeting its minimum green power requirements.

Organizations can choose whether the entire organization or a facility within the organization will become a partner. This flexibility allows an organization to refine its procurement strategy as it purchases or installs green power over time. For organizations not participating at the organization-wide level, EPA recognizes only the participating sub-entity as the Green Power Partner.


By taking advantage of EPA’s tools and resources, technical support, and expert advice, Green Power Partners have found they may be able to save time, effort and cost in buying green power, better estimate the environmental benefits of switching to green power, and better promote their green power commitment to the media and their stakeholders.

Another key benefit to joining the partnership is the gained publicity and recognition EPA can provide. This recognition helps differentiate a company, institution or brand from its competition. Partnering with EPA also lends credibility to an organization’s green power commitment by signifying that it meets nationally accepted standards for product quality and environmental benefits.

The partnership promotes the actions of its partners through a variety of recognition opportunities:

Top Partner Rankings
A key promotional opportunity for Green Power Partners is the programme’s national- and sector-focused Top Partner Rankings. These quarterly-updated ranked lists recognize the largest green power users within certain sectors and the partnership itself.

In July 2009, the partnership debuted its ninth list, which features the Top 20 partners generating and using the most green power on-site – see Table 2.

The Top 20 on-site list represents those partners generating and consuming the most green power on-site within the Green Power Partnership. The combined on-site green power consumption of these organizations amounts to more than 736 GWh of green power annually, which is the equivalent amount of electricity needed to power more than 61,000 average American homes each year.

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Green Power Leadership Awards
Each year, EPA joins with the US Department of Energy and the non-profit Center for Resource Solutions in presenting the Green Power Leadership Awards. These awards recognize outstanding purchases and achievements in the voluntary green power marketplace. Green Power Partners can be nominated for the following award categories: Green Power Purchase, On-site Generation and Partner of the Year.

The On-site Generation award recognizes partners who distinguish themselves using on-site green power applications. Since the inception of the Green Power Leadership Awards, 32 partners have received this award.

Case Studies

Each year EPA’s Green Power Partners raise the bar for innovative on-site green power use. The following case studies highlight how a few of the partnership’s on-site users approach green power.

On-site generation at a college campus
Butte College is situated on a wildlife refuge nestled within the Sierra Nevada foothills of northern California. The college has set a goal of reaching ‘carbon neutrality’ by 2015. To achieve this goal, Butte College is ramping up its on-site solar electricity generation in three phases by more than 1 GWh annually.

The college installed its first 5700 solar panels on a four-acre field in 2005. In 2009, Butte College completed a second phase of on-site generation by installing four additional solar arrays, bringing the total number of panels to more than 10,000. These additional panels generate 1.6 GWh of electricity annually and have saved the college US$300,000 annually in energy costs, reducing its utility bills by one-third. Butte College currently produces 39% of its electricity needs through its solar arrays, generating more than 2.7 GWh per year. Proposals for a third phase are under consideration.

To promote green power and educate the student body on the benefits of on-site solar electricity, the college has placed four interactive kiosks on its campus. The kiosks provide information on the three-phase solar installation plan, solar electricity generation, and real-time solar production.

Meeting sustainability commitments with on-site solar
Wal-Mart is steadily investing in green power as part of its long-term goal of being supplied by 100% renewable energy. During the past two years, the company has taken steps to increase the amount of green power used at its California- and Texas-based stores, Sam’s Club locations, and distribution centers.

In 2009, Wal-Mart’s on-site green power production and wind power purchases are expected to total more than 240 GWh of electricity. Looking forward, the company plans to nearly double its solar energy use in California by installing solar panels at up to 20 additional Wal-Mart facilities by 2011.

On-site generation from landfill
Automaker BMW pipes methane gas 15.3 km from a landfill site to serve the electric and thermal needs of its manufacturing facility in Greer, South Carolina. In 2003, rather than invest in new internal combustion engines to generate electricity BMW converted four turbines that previously ran on purchased natural gas. In 2009, BMW replaced the original four turbines with two new highly efficient turbines, which will increase the electrical output from 14% to almost 30%.

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By recovering the waste heat from the turbines, the 11 MW combined heat and power project satisfies more than 60% of the facility’s thermal needs, as well as nearly 20% of its electricity use. To date, the project has saved the automaker an average of more than $5 million each year in energy costs. The new turbines installed in 2009 should return an additional average annual cost savings of up to $2 million.

With the success of its landfill gas project, the facility is exploring on-site wind and has completed a study of the site’s wind speed and direction.

Using incentives to finance an on-site generation system
The Sierra Nevada Brewing Company installed a 1.2 MW DC fuel cell system at its brewery in Chico, California. The fuel cell is powered by natural gas and supplemented by digester gas from the treatment of brewing wastewater; its waste heat is harvested in the form of steam and used for the brewing process as well as other heating needs. The 1.2 MW of electricity, combined with 1.9 MW solar panels, supplies approximately 90% of the brewery’s overall power requirements.

The capital cost of the fuel cell system was funded by a $2.4 million incentive from the local utility, Pacific Gas and Electric Company, $1 million in financial support from the US Department of Defense Climate Change Fuel Cell Program, and a 30% Federal investment tax credit. These incentives covered about two-thirds of the upfront capital cost for the system.

Procuring on-site generation through solar power purchase agreements
To avoid the large upfront capital outlays required of an on-site power generation system, many organizations have entered into solar power purchase agreements. Under these agreements, organizations host a solar system and agree to purchase its output for a given period of time, while a third-party developer owns, operates, and maintains the system. Two Green Power Partners that have been leaders in advancing the solar services model are Staples and Kohl’s Department Stores.

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Solar panels on the roof of Kohl’s department store, which was the 2008 winner of the EPA On-site Generation award Photo: Kohl’s Department Stores

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The Sierra Nevada Brewing Company installed a 1.2 MW DC fuel cell system at its brewery in Chico, California Photo: Sierra Nevada Brewing Company

Staples has been reaping the benefits of solar power purchase agreements since 2005. As of June 2009, Staples is hosting 24 active rooftop solar systems on its stores, distribution centres and offices throughout the country and has more than 100 more systems under development. The company’s fleet of hosted solar systems totals almost 4 MW and produces about 4 GWh per year. The fixed price for power in the agreements is competitive with local commercial rates and acts as a hedge against price volatility in retail electricity.

In an arrangement similar to Staples, Kohl’s entered into a solar power purchase agreement for a 20-year term in 2007. The company’s near-term goal is to have 125 activated solar locations on its store rooftops. As of October 2009, Kohl’s has 78 solar power systems activated in California, New Jersey, Wisconsin, Oregon, Maryland and Connecticut, with another five in various stages of construction. The company estimates that a hosted solar system provides roughly 40% of a store’s annual electricity needs. Kohl’s is currently the largest retail host of solar electricity production.

Tools and resources

In addition to the expert advice EPA offers, partners can take advantage of a suite of tools and resources:

1. Guide to Purchasing Green Power is an invaluable resource for organizations seeking to use green power. The Guide includes information about the different types of green power products, the benefits of using green power, and how to capture the greatest benefit from the use of green power. The Guide also includes case studies featuring organizations that have been particularly innovative in their approach to purchasing or using green power. To download the guide visit:

2. EPA’s Green Power Partnership Webinar series cover a range of topics relevant to on-site users. Recent topics have included Solar Power Purchase Agreements (SPPAs), on-site use of biomass and biogas, and on-site use of wind and solar. Each webinar features several topical presentations, as well as a brief question and answer session at the end. The presentations for each webinar are archived on the Green Power Partnership website at:

3. The Green Power Equivalency Calculator can help partners communicate their green power usage to interested stakeholders by translating it from kWh into more understandable terms, such as an equivalent number of passenger vehicles, homes or coal plants. The calculator is located at:

4. EPA maintains a special section on its web site dedicated specifically to resources for on-site projects. It provides the latest information on SPPAs; the benefits of using green power on-site; and factors to consider when implementing an on-site system. To learn more, visit:


If your US facilities are considering or already using on-site green power technologies, or if you are interested in learning more, visit to find out how your organization can become a Green Power Partner.