Although the move to renewable energy is pleasing many, some conservationists are concerned that the solar farms are destroying natural habitats instead of being adapted into already developed areas.
(TNS) -- New industrial scale solar arrays in California are displacing natural scrublands along with pastures and farms, says a new analysis of big solar power plants.
The study released Monday by the Carnegie Institution of Science relies on an exhaustive database of existing and pending solar sites, and found that less than 15 percent were located on land already disrupted by human development.
The majority — spanning 145 square miles — are built on natural landscapes. More than 28 percent are located on croplands and pastures.
The study highlights concerns voiced for years by conservationists that California’s boom in large-scale solar energy plants may be carving up desert landscapes in haphazard ways that compromise wildlife habitats and reduce arable land.
"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,” said Rebecca Hernandez, lead author of the study being published in the Proceedings of the National Academy of Sciences. “Instead, we see that ‘big solar’ is competing for space with natural areas. Knowing this is vital."
Ideally, the researchers said, most solar can be located over landfills, parking lots and rooftops. Hernandez and her colleagues held out Germany’s example of putting 90 percent of solar facilities in developed areas.
Bernadette del Chiaro, executive director of the California Solar Energy Industries Association, said the location of large-scale solar development is determined by several factors: proximity and access to transmission lines, land availability and, lastly, permitting issues and opposition from local communities.
“That’s what really drives the patchwork quilt,” she said.
The study does not concern smaller-scale rooftop solar energy systems, which do not count toward California’s mandate for electric utilities to provide 33 percent renewable energy by 2020. More than 250,000 California households and businesses generate their own rooftop energy, in small doses.
Public agencies overseeing state and federal lands have spent years hashing out guidelines designed to minimize the impact of solar, wind and geothermal power plants on delicate wildlife and habitat across 22 million acres of Southern California.
The still-pending framework would streamline renewable energy permitting in select areas within Imperial, Inyo, Kern, Los Angeles, Riverside and San Bernardino counties and a portion of eastern San Diego County (268,000 acres).
Provisions for privately held lands, however, have been delayed despite concerns that development may gravitate toward wide-open public lands. Early critics of the plan include the U.S. Environmental Protection Agency, which long ago identified disturbed and contaminated lands that are ideal for solar.
The Carnegie study looked at solar energy farms of 20 megawatts or larger (about 4,000 times the size of a typical household rooftop array, or greater) across the state. It included both sunlight-absorbing photovoltaic arrays and heat collecting technologies that typically use mirrors to create steam and spin electrical turbines.
Researchers found 161 existing and planned projects as of May 2014, concentrated mostly in the southern reaches of California’s Central Valley, the high Mojave Desert north and east of Los Angeles, and the farming-intensive Imperial Valley.
The study also looked at the location of solar farms in relation to existing transmission lines. It found 19 percent of solar farms were located far from existing transmission infrastructure, suggesting wasteful planning.
“We were surprised to find so few installations were sited in place in the built environment, close to where energy is consumed,” said Hernandez, who currently works at UC Berkeley and Lawrence Berkeley National Laboratory.
Innovative solutions are emerging, such as floating, watertop solar arrays that can limit evaporation at reservoirs and improve panel efficiency with cooling — but may displace water birds.
Hernandez said the published solar study is the culmination of efforts dating back to 2010. She and other researchers discovered there was no single repository for data on the location of solar energy installations, so they created one.
The data are highlighting many unanticipated consequences of solar development.
“Anyone would think that it’s quite oxymoronic that a solar energy plant could actually create or cause environmental degradation,” Hernandez told the San Diego Union-Tribune. “That’s what is happening. ... We make these discrete decisions without a broader reconning on its impacts on landscape stability.”
She said California’s extended drought may be speeding the conversion of cropland to solar energy production, especially in the Central Valley.
That transition may be a win-win, however, on lands that have been heavily contaminated by salt.
©2015 The San Diego Union-Tribune Distributed by Tribune Content Agency, LLC.