A rare desert plant known as the threecorner milkvetch has flourished at the Gemini Solar Project near Las Vegas, Nevada, following construction that preserved the local ecosystem. Scientists observed a significant increase in the plant's population, attributing it to the shading effect of solar panels that reduces soil evaporation. This success highlights potential benefits of ecovoltaics in minimizing environmental disruption from renewable energy developments.
The Mojave Desert, often seen as barren, supports diverse flora including the threecorner milkvetch, a low-growing member of the pea family under consideration for protection under the Endangered Species Act. This plant emerges after rains to flower and reproduce in the harsh conditions.
Traditional solar farm construction involves blading and grading, which removes vegetation and disturbs seed banks. However, the Gemini Solar Project, developed by Primergy outside Las Vegas, adopted a gentler method to protect the habitat. A study published late last year by the Desert Research Institute found that before development, only 12 threecorner milkvetch plants were present on the site. By 2024, post-construction surveys counted 93 plants, indicating the seed bank's survival.
Compared to an adjacent undeveloped area, the plants at Gemini were larger, with greater width, height, more flowers, and increased fruit production. Ecologist Tiffany Pereira, lead author of the study, explained: "So you just have the potential for a lot more plants." She noted emerging seedlings of other species, crediting the panels for shading the soil and slowing evaporation, thus retaining more moisture for growth.
This approach, termed ecovoltaics, prioritizes native species by avoiding heavy disturbance and seeding with local grasses and flowers. Lee Walston, an ecologist at Argonne National Laboratory, highlighted how such seed mixes can attract pollinators, birds, and wildlife, posing the question: "If you build it, will they come?"
Supporting evidence from Minnesota solar sites showed biodiversity gains, including a sevenfold increase in flowering plants and a twentyfold rise in native bees over five years. Factors like panel height influence outcomes, allowing space for taller plants or grazing animals to control weeds.
While challenges remain, such as varying shade needs for different species, ecovoltaics offers a way to enhance habitats rather than degrade them. As Pereira emphasized, "Rather than a moonscape of invasive species and dust blowing into cities, why not strive for something better?"