Foundation Design for Installing Solar Harvesting Systems on Closed Landfills

The average residential retail price of electricity in the United States was 11.33 cents per KW-hour in 2009 which shows a 6.5% increase per year since 2007. The average price of electricity in the US is expected to increase to 15.93 cents per KW-hour by 2015. Florida ranks nationally among the top 5 states in the amount of energy consumed per capita. Even with substantial lifestyle changes, conservation, and energy efficiency improvements, global energy demand is likely to more than triple within next fifty years. Closed sanitary landfills have been developed for different purposes. Although most closed landfills have been developed as open areas and public parks, a number of closed landfill sites have been used for a range of beneficial uses including building sports complex, storage facilities, and shopping malls. Recently, a number of closed landfills have been considered for use as potential sites for renewable energy generation (i.e., from wind or sun). Foundation-cap compatibility is one of the critical factors that must be considered when planning the final site use for closed landfills as power parks. This paper evaluates the compatibility requirements for foundation design for installing solar energy capture systems on closed landfills. Potential challenges associated with foundation design and requirements for support equipment/structures are evaluated. Landfill characteristics and design considerations for controlling leachate and gas generation as well as management of vegetation on closed landfills were evaluated for different types of foundation structures. Technical analyses were conducted to assess the site closure and development needs for suitability of closed landfill sites and necessary foundation requirements for capturing solar energy. Landfill cap design features, wind and snow effects on solar panels, slope, and landfill settlement were evaluated.