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RE-Powering: Key Considerations

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Does the Site have Sufficient Resource?

An initial consideration is whether a site has sufficient resource availability to make a renewable energy project technologically and economically viable. To help make this determination, the Department of Energy’s National Renewable Energy Lab (NREL) has developed maps for various renewable resources and specific projects. 

Additional information and resources for estimating a site’s resource availability can be found below:

  • Solar

    NREL’s Renewable Energy Resource maps provide information at a regional level, while the PVWatts Viewer provides resource based on site address, zip code, or latitude and longitude. The EPA’s RE-Powering Mapper provides information on a site specific basis for a number of federal and state-tracked sites that preliminarily screen well for solar. Also, see SunShot's PV Mapper Tool.

  • Wind

    NREL and AWS Truepower have developed an 80-meter (m) height, high-resolution wind resource map for the United States with links to state wind maps.  In addition, NREL has also developed a national wind resource assessment, as well as a series of wind maps.  The EPA’s RE-Powering Mapper provides information on a site specific basis for a number of federal and state-tracked sites that preliminarily screened well for wind.

  • Biomass

    NREL has developed a series of maps showing the biomass resources available in the United States by county.  Feedstock categories include crop residues; forest residues; primary and secondary mill residues; urban wood waste; and methane emissions from manure management, landfills, and domestic wastewater treatment.  The EPA’s RE-Powering Mapper provides information on a site specific basis for a number of federal and state-tracked sites that preliminarily screened well for biomass.

  • Geothermal

    NREL has developed a series of maps showing currently developed and planned geothermal power plant projects, as well as favorable resources for enhanced geothermal systems and identified hydrothermal sites.  The EPA’s RE-Powering Mapper provides information on a site specific basis for a number of federal and state-tracked sites that preliminarily screened well for geothermal.

How can I Finance a Project?

Project financing varies by project size, as well as local market conditions and available incentives. For many large-scale projects, options range from owner-operator financing, where the system is purchased directly, to third-party power purchase agreements, where the system is owned by an energy developer and the site owner purchases electricity for a given term. Other financing structures include sale/lease back models, which enable the energy user, such as a city government, to use the energy through leasing agreements, while the system owner benefits from tax advantages.

In several states, community solar gardens or virtual net metering policies enable energy developers to partner with consumers who subscribe to purchase power for a given period of time. For large, utility-scale projects, financing is typically provided through project banks. Development of these utility-scale projects typically employs complex financing deal structures. The potential project scale, site owner, market conditions, and renewable energy developer typically dictate the financing option.

For more information on potential financing tools and resources, see RE-Powering’s Fact Sheet on Financing Renewable Energy Projects on Contaminated Lands.

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Are Incentives and Policies Available?

Incentives and policies affecting renewable energy development may be available at federal, state, or local levels. The Database of State Incentives for Renewables & Efficiency (DSIRE), which is operated by the N.C. Clean Energy Technology Center at N.C. State University and funded by the U.S. Department of Energy, is the most comprehensive source of information on incentives and policies supporting renewable energy and energy efficiency in the country.  DSIRE maintains an updated list of possible incentives and policies that may be relevant and available, as well as produces policy maps, reports and provides technical assistance to various stakeholders.

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Will I be Held Liable for Existing Contamination?

To promote the numerous environmental, public health, and economic benefits associated with cleaning up and reusing previously developed property, EPA and states developed brownfields and land revitalization programs. Accordingly, many state and federal laws and policies were changed to address, and in certain situations provide protection against, the liability risk associated with the reuse of contaminated properties, particularly for parties who wish to reuse property that they did not contaminate.

These protections may be applicable to address the potential liability concerns of a developer of renewable energy on contaminated property. EPA has also developed a variety of mechanisms, including policy and guidance and property-specific documents to address potential liability concerns and uncertainty.  Enforcement policy and guidance documents and publications specific to renewable energy development on contaminated properties include:

Generally, only contaminated properties with significant actual or potential public health and/or environmental impacts or those needing immediate attention are likely to warrant federal cleanup. The majority of cleanups are performed under state authority and do not require EPA involvement.

Whether a federal or state law or policy applies to a purchaser or lessee will depend on the facts and circumstances of each case, including, among other things, the developer’s conduct with respect to any contamination on the property.

For more information general regarding EPA’s cleanup policy and guidance, models, and publications, see the Agency’s website Waste, Chemical and Cleanup Enforcement Policy, Guidance, and Publications.

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