IVANPAH VALLEY, Calif. – Construction cranes rise like storks 40 stories above the Mojave Desert. In their midst, the “power tower” emerges, wrapped in scaffolding and looking like a multistage rocket.

Clustered nearby are hangar-sized assembly buildings, looming berms of sand and a chain mail of fencing that will enclose more than 3,500 acres of public land. Moorings for 173,500 mirrors — each the size of a garage door — are spiked into the desert floor. Before the end of the year, they will become six square miles of gleaming reflectors, sweeping from Interstate 15 to the Clark Mountains along California’s eastern border.

BrightSource Energy’s Ivanpah solar power project will soon be a humming city with 24-hour lighting, a wastewater processing facility and a gas-fired power plant. To make room, BrightSource has mowed down a swath of desert plants, displaced dozens of animal species and relocated scores of imperiled desert tortoises, a move that some experts say could kill up to a third of them.

Despite its behemoth footprint, the Ivanpah project has slipped easily into place, unencumbered by lasting legal opposition or public outcry from California’s boisterous environmental community.

The public got its chance to comment at scores of open houses, but the real political horse trading took place in meetings involving solar developers, federal regulators and leaders of some of the nation’s top environmental groups.

Away from public scrutiny, they crafted a united front in favor of utility-scale solar development, often making difficult compromises.

“I have spent my entire career thinking of myself as an advocate on behalf of public lands and acting for their protection,” said Johanna Wald, a veteran environmental attorney with the Natural Resources Defense Council. “I am now helping facilitate an activity on public lands that will have very significant environmental impacts. We are doing it because of the threat of climate change. It’s not an accommodation; it’s a change I had to make to respond to climate.”

That unusual collaboration — along with generous federal subsidies and allotments of public land — has sparked a wholesale remodeling of the American desert.

Industrial-scale solar development is well under way in California, Nevada, Arizona, New Mexico, Colorado and Utah. The federal government has furnished more public property to this cause than it has for oil and gas exploration over the last decade — 21 million acres, more than the area of Los Angeles, Riverside and San Bernardino counties put together.

Even if only a few of the proposed projects are built, hundreds of square miles of wild land will be scraped clear. Several thousand miles of power transmission corridors will be created.

The desert will be scarred well beyond a human life span, and no amount of mitigation will repair it, said scores of federal and state environmental reviews.

“The scale of impacts that we are facing, collectively across the desert, is phenomenal,” said Dennis Schramm, former superintendent at neighboring Mojave National Preserve. “The reality of the Ivanpah project is that what it will look like on the ground is worse than any of the analyses predicted.”

In the fight against climate change, the Mojave Desert is about to take one for the team.

For decades, America’s Western deserts have been storehouses for government scrap, a lode for minerals, a staging ground for military maneuvers.

But the thrum of industry is afoot, bringing Space Age technology and a sense of urgency.

The BrightSource solar plant stands as an exclamation point in the desert.

The $2 billion plant is an amalgam of gadgetry designed to wring the maximum energy from the sun. Computers continually focus the field of mirrors to a center tower filled with water, which will heat to more than 1,000 degrees. The resulting steam drives an array of turbines capable of generating 370 megawatts, enough to power roughly 140,000 homes during peak hours.

Capturing a free, clean source of energy is not cheap. Capital costs and other market factors make solar three times more costly than natural gas or coal.

Ratepayers’ bills will be as much as 50 percent higher for renewable energy, according to an analysis from the consumer advocate branch of the state Public Utilities Commission.

What has opened the way for such a costly source of energy is the dramatic turn in federal policy. As early as 2005, the Bush administration established generous programs to reward renewable-energy developers. The Obama administration sweetened the pot, offering $45 billion in federal tax credits, guaranteed loans and grants.

Ex-Gov. Arnold Schwarzenegger freed large solar plants from property taxes and handed out $90 million in sales and use tax exemptions. Under Gov. Jerry Brown, the state invested more than $70 million in clean-energy research in 2011, funded by a ratepayer surcharge.

The funding has sparked a land rush echoing the speculative booms in mining, railroad construction and oil and gas on Western federal land.

One of the first firms out of the gate was Oakland-based BrightSource Energy Inc., which received $1.6 billion in federally guaranteed loans in addition to hundreds of millions in private capital derived from such disparate sources as NRG Energy Inc., Google Inc., investment bank Morgan Stanley and CalSTRS, the state’s teachers’ retirement fund.

By taking advantage of the available government subsidies, shrewd solar developers can get taxpayers to cover close to 80 percent of a multibillion-dollar project. The rest comes from investors, attracted by what amounts to a tax shelter.

But other companies — often no more than a website and a phone number — obtained solar permits from the federal Bureau of Land Management with no apparent intention other than to sell their place in line. Some sat on the land and never turned a spade of soil.

Federal and state officials have used job creation to partly justify their subsidy of private solar companies. During the two to three years of a solar plant’s construction, most new jobs will go to union tradesmen. But after a plant is built, employment opportunities are limited.

BrightSource’s Ivanpah facility is expected to employ 1,000 workers at the height of construction, but that will fall to 86 full-time maintenance and facility workers once it is up and running.

“The public has bought the whole solar expansion hook, line and sinker because it’s ‘renewable,’ ” Schramm said. “The public would be up in arms if someone was building Disneyland next to a national park.”