Republic Services Inc. this week cemented its leadership in landfill energy production with the dedication of a solar energy cover on its closed Hickory Ridge landfill near Atlanta. The innovative flexible solar cover technology that increases renewable energy output at landfills will generate 1 MW of electricity and meet the needs of 224 homes. The 45-acre closure system, which includes 10 acres of solar panels, is the world’s largest landfill solar energy cap and can be seen from planes using the Hartsfield-Jackson Atlanta International Airport.
As one of the largest solar projects in Georgia so far and only the third application of this solar landfill technology in the country, Hickory Ridge becomes the state’s first landfill solar farm, transforming a closed landfill into a commercial scale, solar energy-generating facility. The cover, a Spectro PowerCap made by Carlisle Energy Services (CES), is a new dual-purpose landfill closure system that allows a landfill owner to close a landfill and also generate renewable electrical power.
“This is a technologically advanced solution that is actually very simple at its core,” said Bob Boucher, senior vice president of operations for Republic. “Given the choice of covering the site with clay and soil, or flexible solar panels, we made the choice that not only caps the landfill with an environmentally safe technology but also produces enough renewable energy to power the equivalent of 224 homes.”
The roughly $5 million investment by Republic is being offset by a $2 million grant of federal stimulus money awarded through the Georgia Environmental Finance Authority (GEFA). Georgia received $82.5 million in American Recovery and Reinvestment Act funding for state energy-efficiency and renewable energy programs.
“GEFA encourages renewable energy in Georgia by funding solar projects such as Hickory Ridge. In addition to funding, we provide technical assistance to state agencies, local governments and private sector companies in developing innovative energy resources,” said Kevin Clark, executive director of GEFA.
Carlisle’s Spectro PowerCap is a dual-purpose landfill closure system that meets regulatory requirements as an alternative closure system and provides clean renewable energy. The system features Carlisle’s three-ply, scrim-reinforced GeoTPO Geomembrane that serves as both the closure system and platform for integrated solar photovoltaics. GeoTPO was developed exclusively for Exposed Geomembrane Solar Cap (EGSC) or Exposed Geomembrane Cap (EGC) applications as both a long-term and final landfill closure solution.
“Our Spectro PowerCap installation at Republic’s Hickory Ridge is a remarkable achievement for the entire team. It confirms our system is viable for large scale solar electricity generation and in meeting state regulatory requirements for landfill closure,” said Arthur Mohr Jr, director of Landfill Solutions at Carlisle Energy Services.
The Hickory Ridge landfill solar energy cover uses nearly 7,000 solar panels to generate more than 1 million kWh of renewable electricity annually. The solar panel area is located on the landfill’s south slope and covers approximately 10 acres of the 45-acre site. The solar array is configured to allow access to landfill utilities such as landfill gas collection wells, while also incorporating cost- effective wiring and efficient electrical operations. The entire array of panels and their accompanying infrastructure are installed on the exposed geomembrane to produce year-round renewable electricity during the 30-year post closure long-term care period and beyond.
The new solar cover will be complemented by a soon-to-be installed landfill gas-to-energy project.
According to the U.S. Environmental Protection Agency, there are about 100,000 closed landfills in the United States, which could potentially represent hundreds of thousands of acres of property that could be used for renewable energy development. Many of these landfills are close to urban areas and have infrastructure in place to deliver solar and other forms of alternative energy economically.