Light on Landfills: Solar Energy Covers Turn Maxed-Out Landfills into Solar Farms
Hickory Ridge landfill solar cover as seen by air when flying into Atlanta's Hartsfield Jackson International Airport (Photo courtesy of HDR Engineering Inc.)
Hickory Ridge landfill outside of Atlanta, GA, is full. Like most landfills that reach capacity, it was capped to contain its noxious mix of debris that will slowly degrade over the decades and centuries to come. But unlike most, Hickory Ridge glistens on a sunny day due its over 7,000 thin-film photovoltaic solar panels plastered to a geomembrane that has been stretched over the hill like a swim cap.
The goal for this new capping system is to create an alternative to traditional landfill covers that will create revenue, boost renewable energy use, and utilize obsolete land, said Mark Roberts, Senior Project Manager for HDR Engineering Inc., the company which developed the technology.
Normally when a landfill closes, the waste is sealed using a polyethylene cap, buried under a couple feet of compacted soil and seeded with grass. The grassy knoll is then effectively useless, albeit somewhat pleasing to the eye.
In contrast, a solar energy cover aims to eliminate the typical maintenance costs of mowing and soil replacement, and instead allows a closed landfill to continue being useful by generating revenue through renewable energy production. This new system uses a durable geomembrane constructed for roofs and fastens it to the landfill with vertical anchor trenches. The geomembrane-covered landfill slopes then serve as a secure and clean surface for the solar panels.
Source: Scientific American
By Robynne Boyd