MOJAVE DESERT — At first glance, California’s vast Mojave Desert seems barren: mile after mile of dust, sand and scrubby creosote bush under a blistering sun. But the huge desert, which spans an area larger than West Virginia, is becoming speckled with gigantic solar power plants that are creating hundreds of construction jobs and, when complete, will generate electricity for millions of homes.

California’s solar Gold Rush is under way, fueled by billions of dollars of federal stimulus funding and a new state law that requires utilities to buy a third of their electricity from renewable sources by 2020. While the collapse of Fremont solar manufacturer Solyndra has dominated the news in recent weeks because it received a $535 million loan guarantee from the Department of Energy, several other solar companies that received loan guarantees appear to be thriving.

The project furthest along is BrightSource Energy’s Ivanpah Solar Electric Generating System, which has been under construction for one full year and is currently being built on federal land near the California-Nevada border with the help of a $1.6 billion loan guarantee. BrightSource, which is based in Oakland, uses mirrors to concentrate the sun and turn turbines that generate electricity. When complete in 2013, Ivanpah will be the largest solar thermal power plant in the world, generating enough electricity for 140,000 homes.

Currently, more than 800 construction workers are on the sprawling 3,600-acre site, which covers an area half the size of Los Gatos. The steel shell of a massive tower that eventually will be taller than coastal redwood trees is rising from the dust near a parking lot filled with cars, trucks and construction vehicles. Most of the workers arrive before dawn to beat the searing late-afternoon heat, and engineering managers pore over plans in air-conditioned trailers.

Ivanpah is one of nine solar thermal power plants approved by the California Energy Commission last year. In addition, scores of other solar projects are in the pipeline. In August, the federal Bureau of Land Management was processing applications for 17 solar power plants in California’s deserts.

Solar currently accounts for less than 1 percent of the state’s electricity, most of which comes from natural gas, two nuclear power plants and hydropower. But advocates — including Democratic Gov. Jerry Brown — want solar to play a key role in the state’s energy future, in part because each project generates hundreds of construction jobs. Brown hopes to add 20,000 megawatts of renewable generation — about one-third of the state’s current power needs — to California’s electric grid by the end of the decade.

“We use a lot of energy in California, and we have aspirations to electrify our vehicle fleet, our ports and to develop high-speed rail,” said Commissioner Karen Douglas of the California Energy Commission. “We need significant amounts of utility-scale renewable electricity.”

Public land at risk?

However, critics and grass-roots organizations such as Solar Done Right fear the West’s last remaining tracts of pristine public lands are being industrialized by “Big Solar” in the name of clean energy, bringing irreparable harm to native plants and threatened species. They want “smart from the start” planning that allows renewable energy development in some parts of the desert while protecting the rest as conservation land. They want residents in the Bay Area and elsewhere to know that California’s deserts are as beloved to some residents as its beaches, parks and redwood trees are to others.

“There’s plenty of desert out there — just put it in the right place,” said Jim Lyons, senior director for renewable energy at Defenders of Wildlife, a national organization that opposes the proposed 4,613-acre Calico Solar Project east of Barstow because of its effects on desert tortoises, burrowing owls and bighorn sheep. “It’s a lot like real estate: location, location, location.”

Solar’s potential

The Ivanpah facility embodies many of the hopes and fears of solar power plants in the desert. It will generate 370 megawatts of electricity, which BrightSource says will displace 13.5 million tons of carbon dioxide emissions over the plant’s 30-year life. Google (GOOG) has invested $168 million in the project, while PG&E and Southern California Edison have signed long-term contracts to purchase the electricity.

“Solar thermal technology projects like Ivanpah are playing a vital role in helping us meet our state renewable goals while providing for a secure and sustainable energy future,” Fong Wan, senior vice president for energy procurement at PG&E, said in a statement.

Unlike rooftop solar panels that directly convert sunlight into electricity, solar thermal plants concentrate the sun’s rays with mirrors or lenses to boil water to create steam; the steam then turns turbines that generate electricity. Ivanpah consists of three separate power plants, each with a 459-foot-tall “power tower” and tens of thousands of mirrorlike “heliostats” — 173,500 in all. While land has been cleared for the construction site, BrightSource has taken pains to leave much of the native vegetation intact. Thousands of pylons protrude from the ground amid vegetation that has been trimmed, but not plowed.

“This has the lowest environmental impact of any project in solar,” BrightSource CEO John Woolard said in remarks to media members who toured the project. “We’re using a minimal amount of water, and there is low impact on the soil and terrain.”

But Jim Andre, a botanist and plant ecologist at UC Riverside, says native plants will not survive under the newly created shade.

“You’re altering the conditions that the species have evolved in,” he said. “It goes against conservation biology 101.”

Concern about tortoise

The biggest environmental controversy at Ivanpah is the endangered desert tortoise. Though BrightSource expects to spend at least $45 million on everything from salaries for biologists to the purchase of thousands of acres of conservation habitat, activists worried about the tortoise protested outside the company’s Oakland headquarters.

While alienating some environmentalists, Big Solar has many supporters among the ranks of the state’s unemployed. Ivanpah is a welcome source of jobs in San Bernardino County, which has been hit hard by the housing crash.

Iraq War veterans Ross Bowlin and Kenneth Platten carpool more than 200 miles from their homes near Riverside to get to Ivanpah, and they share an inexpensive hotel room in Nevada during the workweek. Both obtained their jobs via “Helmets to Hardhats,” an apprentice program that helps veterans transition to careers in the construction trades.

“Before this job I had no construction experience at all, and I was on unemployment for a while,” said Bowlin, a former Marine who served two stints in Iraq. “But this job reminds me of being in the military, in that we have a job that’s bigger than ourselves. We’re facing an energy crisis.”

Platten, who served in the Army, misses the adrenaline rush of war but says the sheer scale of Ivanpah gives him a different kind of thrill. The good wages — about $35 an hour — help make up for the long drive. In addition, he’s used to the desert heat: The deserts of Iraq are even hotter than the Mojave.

“We’re building the biggest solar thermal power plant in the world,” he said, as he surveyed the power tower. “To see this going up is amazing. I can look out and know that I hauled some of that iron, and that’s cool.”

Sprouting like weeds

Ivanpah is not BrightSource’s only project. The company has filed applications with the California Energy Commission to build two other large solar power plants: the 500-megawatt Hidden Hills project, in California’s Inyo County, and the 750-megawatt Rio Mesa project in Riverside County.

“There’s so many companies submitting plans and filing for permits that it’s hard to keep track,” said Laura Cunningham of Basin and Range Watch, a volunteer group fighting “energy sprawl.”

“You basically have a few dozen activists trying to protect this huge desert,” she said. “Each solar project is on a different type of ecosystem, and there hasn’t been a lot of planning. It’s been, ‘There’s sun, let’s build a power plant.’ “

Cunningham grew up in the Bay Area and moved to a rural mining town in southern Nevada 10 years ago. A biologist and reptile expert, she has grown to love the desert, and the sense of calm and wonder it inspires.

“You can go into the desert and feel like you are the only person in the world,” she said. “And yet it’s teeming with life: jack rabbits, burrowing owls, rattlesnakes. In the spring, we have the most spectacular wildflowers, and the whole desert erupts in blossoms.”

Conservation plan

In an effort to resolve conflicts between solar companies and conservationists, California is developing a Desert Renewable Energy Conservation Plan to decide which parts of the desert will be open for renewable energy development and which parts will be protected.

“Initially, all of these big solar projects were being crammed down our throats,” said Ileene Anderson, a biologist with the Center for Biological Diversity who is active in the conservation plan’s process. “But now the state is realizing that you can’t just bully projects into being — you have to take a close look at where they are sited. Climate change is real, and we have to transition to renewable energy. But let’s do it without driving species to extinction.”

Contact Dana Hull at 408-920-2706. Follow her at Twitter.com/danahull.