The Sustainable Campus (Trends and Innovations)

Pollinator-Friendly Solar

Denison University, a private liberal arts university in Granville, OH, strives to be an exemplary steward of the natural world and a leader in sustainability. Denison takes an intentionally multidisciplinary approach to sustainability that balances environmental, economic, and social responsibility.

A Solar Commitment

Clean, renewable solar energy is a growing part of Denison’s commitment to sustainability. That commitment began in the 1960s with the foundation of the Biological Reserve, a 350-acre parcel set aside for student and faculty research as well as enjoyment by the community. It continued with the establishment of the Homestead in the 1970s. An alternative student living arrangement, off the energy grid, the Homestead is one of the first such communities in the country and is still going strong today.

In addition to three rooftop solar arrays on campus, Denison’s newest solar array, activated in December 2017, was established to generate 2.3 MW of power, about 10 percent of the college’s energy use. For this installation, Denison provided about 10 acres of “compromised” land from which the top soil had been removed for other uses and scrub trees and nonnative plants had filled the void.

Today, that land is a pollinator-friendly solar habitat.

Solar Installation at Denison Univerity

Denison’s pollinator-friendly solar array is the first of its kind in Ohio and the first in a five-state area, demonstrating an innovative and productive use for the land under and around groundmounted solar panels.

Denison’s ground-mounted solar array has a generation capacity of 2.3 MW solar array and produces 2,800,000 kWh annually. It is home to more than 1,000,000 flowering and pollinator-friendly plants. Only in its first year, the pollinator habitat already is teeming with butterflies, bees, and other beneficial insects. They, in turn, are attracting and supporting birdlife in the adjacent 350-acre Biological Reserve.

A Team Project

“So many people from all different interests came together to build this project,” says Jeremy King, Denison’s sustainability coordinator. Key partners in the project include Pheasants Forever, AEP Energy, U.S. Fish and Wildlife, Third Sun Solar, and the Center for Pollinators in Energy at Fresh Energy. “It was heartening to see how a pollinator habitat could become a common goal for everyone.”

King also will join the advisory committee to a 25-site study over 10 states being led by the National Renewable Energy Laboratory to examine best practices in vegetation establishment and management on solar arrays. Preliminary results of the study, named InSPIRE, indicate that establishing a low-growing meadow, rather than using gravel or turfgrass, leads to reduced operations costs and can influence panel efficiency by creating a cooler microclimate under the panels.

“Denison University’s leadership reveals a simple fact—when buyers specifically ask for energy from a pollinator-friendly solar array, the resulting partnerships and landscape are beautiful,” says Rob Davis, co-chair of the InSPIRE study advisory committee and director of the Center for Pollinators in Energy at nonprofit Fresh Energy.

“We applaud Denison University’s leadership and landscape stewardship and hope to see it become a standard practice for large-scale solar throughout the region,” said Michael Retterer, state coordinator for Ohio Pollinator Habitat Initiative and Pheasants Forever.

Exceeding Expectations

The 10-acre solar array significantly exceeds the beneficial habitat threshold established by Ohio Pollinator Habitat Initiative, a consortium of more than 80 organizations including representatives from government agencies and conservation organizations.

Some fun facts about the Denison Pollinator Habitat:

  • Native bees, monarch butterflies, and grassland birds populate the habitat.
  • Plants include Golden Alexander, Showy Black-eyed Susan, Mountain Mint, and Heath Aster.
  • The site provides habitat equivalent to more than 6,000 homes each planting 6-foot-by-12-foot pollinator gardens and then maintaining them for 30 years.
  • The Solar Site Pollinator Habitat Planning and Assessment Scorecard, published by the Ohio Pollinator Habitat Initiative, establishes a standard for pollinator-friendly solar.
  • The deep-rooted native plants are better at stormwater and soil retention and more resilient to new weather patterns.
  • Mowing only once per year cuts down on energy use.
  • Thicker vegetation under solar panels creates a cooler microclimate. Panels can run more efficiently, providing peak performance and extending longevity of the panels.
  • The site is managed to be free of noxious/invasive weeds.