Solar photovoltaic energy developers are always looking for large, flat, available pieces of land to install arrays of panels in “solar farms.”
So far that has included hundreds of the 10,000 landfills across the United States identified as closed by the Environmental Protection Agency and other “brownfield” sites where trees have been cleared, like former gravel pits and phosphate mines. It’s also led to numerous installations of solar PV panels over parking lots to create “solar carports” protecting vehicles underneath from exposure to weather.
In some areas, the quest has turned especially creative: Solar panels in the grassy strips alongside the Massachusetts Turnpike. Four solar projects planned in Japan at abandoned golf courses. Even a solar-PV-incorporating bike path in the Netherlands called the SolaRoad.
Here at TRC, we’ve recently come to appreciate another abundant and underutilized source of open space highly suitable to solar farms: the old surface and underground coal mining sites of the U.S. Midwest. In developing lists of solar PV candidate sites for clients, we’ve identified an abundance of sites in Illinois, Indiana, Kentucky, and Ohio comprising hundreds, sometimes even thousands, of acres of open grasslands left behind following post-mining reclamation work.
Unlike situations where solar developers may have to negotiate with reluctant landowners, owners of former mine sites are almost always highly motivated to lease or sell them to get them back into economic productivity. Also, besides being treeless and flat, ex-mining sites are located next to existing roads and often power transmission lines and electric-grid equipment that connected to former mine substations. Having that existing infrastructure in place can accelerate the process of interconnecting a solar PV array to the grid.
Many of these surface mine sites were reclaimed decades ago, so the land has had plenty of time to settle to a flat, stable topography. Most are in remote rural areas with few adjacent landowners, where sites are large enough to allow the designation of buffer areas separating solar PV from neighbors to ease potential siting objections.
Retired underground coal mines can also present opportunities. While the surface footprint is smaller than surface mines, the refuse disposal areas near reclaimed underground mines can often provide up to a few hundred acres of solar development potential. Unlike old municipal trash landfills that have been capped but still contain material that is biodegrading and settling, most underground coal mine disposal areas are comprised of a stable mix of coarse and fine coal refuse under 2 to 4 feet of soil vegetated with grass or other ground cover.
While these are big, easy sites to work with, you’ll still need to bring in experts from an organization like TRC to do the right homework. That will include evaluating what mix of rocks, glacial till, silts, clays, and sands you have at each site and what procedures will be necessary for driving piles and installing racking systems. You’re also well advised to call or visit the local mining regulatory authority to examine the reclamation plan on file and obtain valuable information about the post-mining conditions.
What you’re likely to find are many large, ideal locations for solar PV farms that can represent a fascinating next chapter in the story of how we get and use energy: The very same locations where coal mining drove the Industrial Revolution in the 19th century can now be some of the biggest-impact locations driving the Green Energy Revolution in the 21st century.