Planting the Seeds for Solar: The Multiple Benefits of Pollinator-Friendly Vegetation in Solar Fields | Article

Solar power is a blossoming source of renewable energy. In 2020, 43 percent of new electricity-generating capacity built in the United States was solar. As these projects proliferate, it’s critical to ensure that solar installations are designed with the wellbeing of the surrounding environment in mind. Solar arrays are land-intensive, projected to take up 3 million acres by 2030, which has sparked some to find solutions that lower the impact of solar sites on the land.

One solution that has gained popularity is planting vegetation—with an emphasis on native and flowering plants—between rows of solar panels. This dual use of land bolsters pollinator populations, whose rapid decline in recent years threatens agriculture in the United States and globally.

A solar field with pollinator-friendly plants in Minnesota. Photo courtesy of Fresh Energy.

As part of its InSPIRE initiative, the National Renewable Energy Laboratory has collected data on a number of solar projects across the country that have implemented pollinator-friendly vegetation, and it has found a wide array of benefits. At three solar sites in Minnesota, the InSPIRE team observed a threefold increase in beneficial plant species between 2019 and 2020 and a fourfold increase in pollinators between 2018 and 2020. In addition to providing habitat for pollinators, native plants also help store water in the soil during storms and droughts and improve soil health, even in areas with polluted soils.

Importantly for solar facility operators, planting ground cover on-site can also raise energy output. Compared to traditional solar farms, those that integrate plants into their solar arrays have lower ambient air temperatures, which enables higher energy output. This approach also could lower costs because it requires less ongoing maintenance than turfgrass and circumvents the need to remove topsoil during site preparation.

Since much of the land that will be developed for solar is privately owned, it’s important to think about the private sector's role in making new solar projects more environmentally friendly, and several companies have already begun to do so. Presenting at a Greenbiz webinar, “Amplifying the Sustainability and Biodiversity Benefits of Solar,” Elysa Hammond, Clif Bar's senior vice president of environmental stewardship, discussed the company’s new bakery in Idaho that lives up to its ‘think like a tree” philosophy of being regenerative and emissions-free. This zero-waste facility is completely powered by seven acres of on-site solar panels and pollinator-friendly plants. Other features of the facility include solar panels over the employee parking lot for powering and shade, educational information for visitors, and even “solar honey” from the bees that thrive in the solar field.

Other companies such as Bank of America, Organic Valley, and Aveda, as well as several universities, have also integrated this pollinator-friendly approach to their solar installations. Bank of America, which also presented at the Greenbiz webinar, recently signed contracts for 80 megawatts of new solar arrays in the Carolinas, all of which include pollinator habitat.

As companies across sectors begin incorporating native vegetation into their solar projects, Fresh Energy, a Minnesota-based company paving the way for pollinator-friendly solar design, identified a need to assess the impact of these pollinator-friendly measures. They developed the Pollinator-Friendly Scorecard, which assigns points to various attributes of project design, including the percentage of the site covered by vegetation, the percentage of the site dominated by native vegetation, and the diversity of cover species. In the Greenbiz webinar, Rob Davis, director of the Center for Pollinators in Energy at Fresh Energy, said that the scorecard was developed in part to address potential “greenwashing,” which is when companies exaggerate the environmental-friendliness of their products or company to impress customers. The scorecard can help keep companies accountable and motivate them to pursue plans that will have the greatest benefit for pollinators.

Looking to the future, it is clear that solar must take up a larger share of the energy market if the United States is to decarbonize quickly enough to combat climate change. Adding pollinator vegetation is a low-cost intervention that can make solar an even bigger win for the environment.

Author: Anna Sophia Roberts