America’s eyesores are becoming the hot places to install renewable energy for electric power generation. The land is cheap, often abandoned but properly zoned. They’re usually close to necessary infrastructure such as power lines and roads, and no other developers are rushing to erect anything on them. The U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) is evaluating sites for renewable energy potential on behalf of the EPA.
Brownfields could be former industrial sites abandoned when the owners went bankrupt. There might have been paint or fuel spills there, but the exact source of contamination may be unknown. However, superfund sites usually have a responsible party identified. Some brownfields are ready for redevelopment, but others need a lot of work first.
Photographing the sky for its solar potential
Salasovich and other traveling NREL engineers start with a device called a SunEye, which has a fish-eye lens to photograph the sky above the landfill. “We point it south and take a photo,” he says. “It puts out a spherical graph and shows where the shade will be by what time of day and what time of year.” An algorithm built into the device can detect differences between the sky and a tree.
If a site has wind potential, the engineers install a meteorological tower with instruments to read wind speed and direction, according to Joseph Roberts, an engineer with the National Wind Technology Center at NREL. After 12 months of measurements, they can find an average speed and see how it compares with data from nearby airports. Crew members also check the distance to the nearest roads and transmission lines, evaluating the sites’ potential for generating renewable energy and making it work economically.
NREL Engineers select potential plots from the EPA’s list of superfund and brownfield sites, as well as those identified by the Resource Conservation and Recovery Act (RCRA). In some cases, the renewable energy apparatus in construction is powering the ongoing clean-up efforts at the sites. In other cases, the wind turbine, solar array, or hydro power is sending power to nearby cities. This is most feasible when the site is close enough to transmission wires to tie into the grid. There are about 11,000 sites in the U.S. with some past or current environmental contamination problem that may hold potential for renewable energy, according to Gail Mosey, senior energy analyst in the Strategic Energy Analysis Center. She says it’s a great opportunity to reuse land for power generation without help from fossil fuels.
Erecting devices without disturbing the contamination
Some sites, particularly superfund sites, are so contaminated with toxic chemicals and heavy metals that the earth should not be disturbed. However, Mosey explains, “There are a lot of others that can endure a slight intrusion. There are workable solutions for installing renewable energy on the surface or outside the contaminated area.” For example, solar arrays fit comfortably on top of the two feet of dirt and liner that typically cover a condemned landfill.
There are even wind turbines (supported by surface-mounted concrete footing) that can generate energy without burrowing into the muck of a superfund site. “These are places where you wouldn’t necessarily want to put a housing development, pour a foundation, or have people plant backyard gardens,” Mosey says, “but they are excellent sites for renewable energy.”