A new study sounded the alarm on how solar power plants in sunny California may be compromising natural habitats and harming biological diversity in certain areas.
Rebecca Hernandez of University of California Berkeley and Madison Hoffacker of University of California Riverside found that a majority of solar power sites are on natural landscapes spanning about 145 square miles. On Oct. 19 the team published their findings in the Proceedings of the National Academy of Sciences.
Around 85 percent are located in undeveloped areas, while about 20 percent are far from transmission networks, entailing “adverse economic, energetic, and environmental consequences.”
The report covered 161 existing and planned large-scale Californian solar energy facilities, including the farming-intensive Imperial Valley and the southern reaches of the Central Valley.
The study comprised two solar technologies in built-up areas: photovoltaics and concentrated solar power, both of which were found in previous research by Hernandez’s team to potentially meet the state’s energy needs “three to five times over.”
California serves as a good model for understanding utility-level solar energy development because it is an early adopter of the renewable energy, said Hernandez.
“Solar energy in developed areas, or for example on contaminated lands, would have great environmental co-benefits, but this is not what is being emphasized. Instead, we see that ‘big solar’ is competing for space with natural areas,” she warned.
The team calculated the proximity of solar installations to protected habitats. For instance, 20 percent of the solar facilities were distant from transmission infrastructure. This translates to energy traveling farther, resulting in greater energy expenditure, increased spending, and the degradation of natural surroundings caused by new transmission modes.
On how nearly 30 percent of all solar installations were found in croplands and pastures, Hernandez said that landowners specifically in the Central Valley are shifting from crop and forage harvesting to harnessing the sun – likely due to drought.
The lead researcher explained that reducing the United States’ greenhouse emissions by 80 percent of 1990 emissions by the year 2050 means using 27,500 sqm. of land (around South Carolina’s size) for solar installations.
She recommended efficient land use through reducing “spaces between rows of photovoltaic modules or concentrating solar power mirrors,” or placing the installations in already-developed areas such as landfills, parking lots, and rooftops.
California Solar Energy Industries Association Executive Director Bernadette del Chiaro said that several factors affect large-scale solar developments, including land availability, access to transmission lines, land use permits and local community opposition.
California mandates electric utilities to offer 33 percent of renewable energy by 2020 – something that does not involve smaller-scale rooftop solar energy systems.
Public agencies are still creating guidelines on minimizing renewable plant impact on natural habitats across 22 million acres of Southern California.
Photo: Uwe Potthoff | Flickr