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Using Landfills for Solar Farms

published: 2012-07-30 16:59

By D.A. Barber

With large tracts of land at a premium, a new development trend in the U.S. has opened unused locations for solar developers who are willing to build on landfills or formally contaminated lands in various cities around the country. Such old industrial sites and landfills that have been cleaned-up to a certain degree are known as "brownfields" in the United States. These mostly urban lands have traditionally been re-developed into parks and business centers in the past, but they are now being looked at as sites for locating clean energy technologies like solar. One example is that the U.S. Department of Energy is currently taking bids in Colorado to build a solar-power facility on a 42-acre former uranium mine site which currently holds uranium mine tailings.

Brownfields, according to the Environmental Protection Agency (EPA), is real estate where development “may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.” Because these hazardous substances more times than not will seep into the soil, cleaning-up the site to establish a new business is usually more costly than simply locating the business elsewhere. Yet, it is because these undeveloped dead zones are limited to what they can be used for that they are ideal for renewable energy projects since the land has already been disturbed and there’s no threat to impacting wildlife the way giant solar farms become a concern when they’re built in pristine areas. Another reason brownfield sites are being sought out by renewable energy companies is the fact the locations that were once factories or industrial sites already have close access to the electric grid infrastructure needed for transmitting the power.

The National Brownfield Association reports that there may be as many as 1 million brownfields in the U.S. and their real estate value would total some $2 trillion if they could be used for traditional building projects. The City of New York recently launched “SPEED,” a database developers can use explore some 3,150 vacant commercial and industrial brownfield sites spread throughout that city. The City has also launched a $9-million brownfield re-investment fund to nudge developers toward committing to re-developing a brownfield, especially for energy uses.

DOE and “Brownfields”

In 1995, the EPA initiated the Brownfields Program to provide research and funding for cleaning up contaminated land for development. The agency then launched their RE-Powering America’s Land program in 2008, which provides incentives for re-developing brownfields specifically for renewable energy production.

Now the EPA has combined its brownfield expertise with the renewable energy expertise of the Department of Energy’s National Renewable Energy Laboratory to speed the development of renewable energy brownfield projects. With help from DOE, RE-Powering America’s Land Initiative is investing a $1 million for the assessment of projects across the United States. The assessment of the brownfields will determine the best renewable energy technology and placement, potential energy generating capacity, estimated return on investment, and economic feasibility of the renewable energy projects.

The EPA solicited applications from states, tribes, and governments that are interested in the development of renewable energy on current and formerly contaminated land. The plan, announced in April 2011, is to spend 18 months assessing 26 former landfills and brownfields located in New Mexico, Arizona, Colorado, Montana, Vermont, New York, New Jersey, Delaware, Georgia, Mississippi, Illinois, Indiana, Louisiana, Iowa, Missouri, Kansas, Nebraska, California, Oregon and Washington.

Project Success

The current project is not a new idea. According to the EPA, there have already been over 20 renewable energy projects either built or under construction on contaminated brownfield sites around the United States. One example is the 10MW Exelon City Solar project in Chicago built on a former 41-acre industrial brownfield property that had been vacant for over 30 years. Now the nation’s largest urban solar power plant, Exelon City Solar contains 32,292 PV panels.



Other examples include:

  • The Hawaiian Electric Company signed an agreement in August 2011 to purchase power generated by a 1MW PV plant at the Kapolei Sustainable Energy Park, a former industrial disposal site on Oahu, Hawaii. The plant will use more than 4,200 PV panels mounted on a sealed 12-acre industrial waste site where dumping was halted in 1986 and the property deemed unusable by the federal EPA.
  • In Springfield, Massachusetts, the Western Massachusetts Electric Company is turning a local landfill into a 4.2MW solar facility by installing some 17,000 PV panels, making it New England’s largest solar facility.
  • In November 2011, China-based ENN Solar Energy announced it had partnered with National Energy Renewable Corp. to turn an East Brunswick, New Jersey, landfill into a 4.3MW solar site using thin-film PVs that will “float” on the landfill cap without puncturing it and releasing the flammable methane gas that has the built-up over the years.

Landfill Solar Farms in Europe

It seems that the use of contaminated wastelands for sitting solar projects is an American phenomenon for the time being. For example, European environmental laws have favored the development of waste-to-energy programs rather than using landfills for solar. Part of this is because the European Union has rigorous restrictions on the creation of new landfill sites. In the UK alone, 22 such “waste-to-energy” facilities are in operation, and countries like Denmark and Germany have been expanding their waste-to-energy capacity. In fact, Denmark regards garbage as a “clean” alternative fuel.

The most common technology to convert waste into fuel is the gasification process, which involves heating waste at very high temperature to breakdown the chemical bonds and convert it into usable gas which burns like natural gas to create energy. Critics maintain that the benefits of such incineration are environmentally questionable due primarily to concerns over emissions. Another concern is that it diverts waste from recycling, which critics say is a better investment since it re-uses the waste products. And once you build “waste-to-energy” power plants, you have to “feed” them, taking away any economic incentive to retrieve the usable materials from the waste.

Interestingly, there are only about 87 waste-to-energy power plants in the United States, most built at least 15 years ago with no new ones planned despite the fact the both the U.S. government and nearly half the states classify it as a “renewable energy.”


Locating solar projects, especially large-scale solar arrays, near urban areas without sacrificing valuable greenspace that contributes to the “quality of life” has begun to surface as an issue in the United States. The country’s industrial development also has a long history of using and then abandoning lands that have ultimately left a legacy of unusable “superfund” hazardous waste sites, unattended landfills or mining waste dumps. The ability to use these brownfield lands for renewable energy technology seems to have the potential of solving two issues at once.

The information that comes from the U.S. Department of Energy’s brownfield-to-energy assessment on even the few selected sites it has chosen has the potential to not just determine how technically feasible development of such renewable energy projects are, but also the economically feasibility of expanding to concept to much larger contaminated sites.

The criteria for a landfill site to accommodate current solar technology includes the site be fairly level with little vegetation and adjacent to the local utility power line grid. According to the joint data from the EPA and NREL, there currently exist nearly 4,100 waste sites in the U.S. already determined to be economically and technically feasible for renewable energy development.

The data collected from the projects that develop from the current DOE assessment could go a long way toward nudging more solar firms to take on the bigger challenges and, in turn, boost the solar industry as a whole as the need for more specialized and site-specific equipment increases. This could open unanticipated opportunities for new start-up companies focusing on this particular solar development niche. In fact, if this wasteland development trend expands to other countries, the market could become vast.

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