Turning Landfills Into Places Where Solar Power Is Developed

(3BL/JustMeans) The number of active landfills that receive municipal solid waste across the country have been decreasing. There were almost 8,000 of them in 1988, but less than 2,000 by the mid 2000s. What happens to landfills that are no longer active anymore?

Most landfills are about 40 acres. There are literally millions of acres of space not being used in the U.S. One solution to make good use of inactive landfills is to generate solar power on them. The federal government encourages renewable energy development on active and inactive landfills through the EPA’s RE-Powering America’s Land Initiative. Through the initiative, former landfills now have solar arrays.

Most landfills are in the warmer, sunnier regions of the county, with almost 40 percent in the West and 35 percent in the South. Only seven percent of landfills are in the Northeast, but Massachusetts has become a leader in solar development on landfills. Massachusetts even has a guide for developing solar photovoltaics (PVs) on landfills. Vermont is another Northeast state that has embraced landfill solar. A solar array of 300 PV panels are being developed on an inactive landfill in South Burlington which has not been used for 25 years. The solar array will sit on about eight acres of the landfill and generate 2,665,000 kilowatt hours (kWh) a year, enough energy to power almost 400 homes.

The Northeast is not the only area to develop solar energy on landfills. And inactive landfills are not the only ones with solar developments. One of the largest solar energy facilities in Georgia sits on an at-capacity landfill. It is the largest solar energy cap in the world and the first time the technology has been used as a landfill final closure system. Instead of a traditional cap for the landfill, an enhanced geomembrane is used, and thin-film PV panels are put on top. There are more than 7,000 PV panels that generate over one megawatt of energy. The solar cap means that thousands of greenhouse gases (GHGs) are prevented from being emitted like they would be with a traditional cap.

Landfills with municipal solid waste are not the only ones to feature solar power. In Wisconsin, a 17 acre capped coal combustion residual landfill now features over 7,700 PV panels that produce 2.3 megawatts (MW), enough energy to power 500 local homes. Called the Rock River Solar project, it is the largest solar power site in the state famous for cheese.

Solar power on landfills provides clean energy and solves a problem of what to do with either inactive landfills or ones that are at-capacity. Instead of letting acres of unused land just idle, they can be used to harness the power of the sun.

Photo: HDR, Inc.