Poster Spotlight: Putting Together the Pieces for Sustainable Land Management on Solar Sites

Description and Background: Establishment of sustainable vegetation is integral to stormwater management and compliance with provisions of the US Environmental Protection Agency (EPA) Clean Water Act (NPDES) and other state and local environmental regulations or requirements. Development of solar sites often involves clearing and denudation of large tracks of land. Moreover, placement of access roads, buildings, electrical equipment, arrays, and panels create impervious surfaces and accelerated stormwater runoff. Vegetation holds soil in place which reduces and filters sediment discharges and ultimately sedimentation into receiving water bodies.

Successful establishment on solar sites can be problematic when proper measures and methods are not implemented. Several challenges emerge when large areas are stripped of existing vegetation. Topsoil is difficult to salvage and be stored properly, often resulting in poorly developed soils where restoration efforts are required. Seed mixes must be carefully selected to ensure the plants are locally adapted, preferably low growing and suitable for the creation of habitat for forage and/or pollinating insects.

Furthermore, development of sustainable vegetation consisting of natives and pollinators can reduce operation and maintenance costs and have been documented to offer Returns of Investment (ROI) within 3 to 8 years versus fast growing turf and other species. When fully established, stands of natives and pollinators develop extensive root systems that can sequester nearly twice the amount of carbon versus shallow rooted turf grasses. Lastly, photovoltaic energy production is enhanced when surface temperatures are lowered by dense stands of vegetation versus bare or sparsely vegetated surfaces or especially synthetic turf.

Beyond these considerations are properly installed erosion control measures to protect the soil and facilitate vegetative establishment. After installation the solar sites must be inspected and properly maintained for a typical 30-year design life. Designers must be mindful to create and maintain access for equipment needed for seeding and erosion control as well as the maintenance equipment.

The importance of this holistic approach cannot be understated as we learn more about pollinator habitat requirements and the significant O&M cost reductions enjoyed when employing low growing native vegetation. The experienced and esteemed group of panelists will offer insight on various aspects to ensure cost -effective and sustainable land use on solar sites.

The subject matter is highly relevant to those seeking guidance on proper design and installation of sustainable vegetation with reduced maintenance costs on their solar sites. In addition, this guidance can assist those who have experienced less than desirable results on previous efforts to stabilize and restore their solar sites. Remedies to correct failed measures will be discussed.