WThe appearance of lush hills is created when hen landfills are grassed and capped. Despite their green appearance, however, these sites are known as “brownfields”—a term for an environmentally hazardous site without a promising future. Because of the contamination and physical instability below, landfills can be unsuitable sites for development.
But what they can be repurposed for are solar farms, and these so-called “brightfields” are growing in number and size.
According to the World Resources Institute (RMI), an organization which promotes clean energy, last year local governments in the United States announced that they would generate 207 megawatts from 21 landfill-based solar energy projects. That’s a 10-fold increase in energy capacity compared with recent years, and it includes the three largest projects in the country to date.
It is indicative of the growing interest in clean energy by cities to pursue ambitious projects. One brightfield deal, which was announced in September last year, generates 50 megawatts. A second project with similar potential was announced last September on the same site in Columbus, Ohio. It is located in Houston, Texas, and covers 240 acres. These two projects together account for about half the brightfield energy that was announced last year and will each power approximately 5,000 homes per year.
While it’s not unheard of for capped landfills to become parks or golf courses, solar farms can be a more feasible alternative, as there’s no need to prepare or maintain the site to accommodate the public. Also, solar farms can leverage resources found nearby landfills like roads and electric infrastructure. Brightfields, unlike traditional golf courses, harness clean energy sources that can be distributed to large populations. This helps to address environmental injustices experienced by people who live near landfill sites.
There is enormous potential for these types of projects on a nationwide scale. Based on an RMI brightfield analysis from late 2021, closed landfills could host more than 60 gigawatts of solar capacity—enough energy to power the state of South Carolina.
However, it will not be easy. Brightfields are subject to different regulations and costs due to the terrain they are located on. “There’s more due diligence, there’s more design and engineering, and people’s time that has to go into sufficiently planning this,” says Matthew Popkin, an urban transformation manager at RMI. “If you put a stake in the grass in a random field poorly, the dirt might suffer. If you put a stake in a landfill poorly, the community might suffer.”
These barriers can be overcome. It is easier and cheaper to plan large-scale projects than for smaller ones. Brownfield cleanup grants can be provided by the state and federal governments to offset some of the costs. The cost of future solar projects could decrease as the industry learns and improves its best practices.
“Local governments are really pushing their clean energy goals,” says Popkin. “And sure, you can put 200 kilowatts on your city hall. This can be placed on buildings and fire stations, as well as a few other facilities. But when you start to look at municipally owned land that is in your control and that is able to host a large project, suddenly a brownfield or a closed landfill looks very attractive because it can’t be used for … housing, mixed-use apartments, or the next Walmart or Target superstore.”
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