When biologists began surveying more than 4,000 acres on the eastern end of the California Valley earmarked for a large solar project, they knew the area was home to kangaroo rats. Signs of the rodents’ large burrows — biologists call them precincts — were visible everywhere.
However, it wasn’t known whether the kangaroo rats were the endangered giant species or the more common Heermann’s variety. Biologists eventually determined they are giant kangaroo rats and that they are scattered throughout the center of the area proposed for the 250-megawatt photovoltaic power plant.
That piece of information sent project proponents SunPower and county planners scrambling back to the drawing board. They had to rearrange the tens of thousands of photovoltaic panels to avoid the kangaroo rat’s habitat.
“It was a surprise that so many giant kangaroo rat precincts were found in the project area,” said John McKenzie, county planner for the project. “That meant that we had to look more closely at some of the other alternatives.”
County planners also looked at the feasibility of relocating the project to the Central Valley, where decades of intense agriculture and oil development have already eliminated most endangered species such as the giant kangaroo rat.
That is the option Susan Harvey, president of the Paso Robles-based group North County Watch, would prefer. She would also like planners to consider developing rooftop solar rather than allowing large commercial power plants in ecologically fragile areas.
“I think it’s unfortunate that there is this prevailing attitude that we need to destroy the environment in order to save it,” she said.
Both the county and SunPower have come up with redesigned projects that minimize the impact on giant kangaroo rat habitat. Both versions use a new model of rotating solar panel developed by SunPower that lies closer to the ground and requires less land.
However, the two proposals differ significantly in other ways. The main difference is that what the county calls its environmentally superior alternative calls for the project to be scaled back 30 percent from 250 megawatts to an estimated 175 megawatts.
SunPower’s alternative proposal calls for the size to remain at 250 megawatts. To do this, some of the arrays (solar panels clustered together in groups) would be moved to areas with less desirable terrain. SunPower plans to use as many as 88,000 solar panels.
Specifically, a group of arrays would be placed on the north side of Highway 58 on steeper terrain. Another group of arrays would be placed on the site of a defunct gypsum mine.
“The great thing about this property is that we are able to move arrays around to meet our goals,” said Greg Blue, SunPower’s outreach coordinator.
SunPower’s revised project is a “close second” to the county’s reduced acreage alternative, McKenzie said. However, planners balked at embracing the solar company’s option for several reasons.
First, moving some of the arrays north of Highway 58 means that they would be on both sides of the highway, increasing the visual impact of the project. Also, putting arrays on steeper ground and reclaiming the gypsum mine would require more grading, increasing air pollution impacts.
SunPower will try to convince county planners that keeping the size of the project at 250 megawatts is worthwhile because it better helps the state attain its ambitious alternative energy goals, Blue said.County planners hope to have a formal recommendation of which alternative to choose when the Planning Commission takes up the project in January.
An environmental impact report for a second photovoltaic plant in the California Valley, the 550-megawatt Topaz Solar Farm, is expected to be published by the end of the year.
Reach David Sneed at 781-7930.