SAN FRANCISCO — Proposals for the first large solar power plants ever built on federal lands won final approval on Tuesday from Interior Secretary Ken Salazar, reflecting the Obama administration’s resolve to promote renewable energy in the face of Congressional inaction.
Both plants are to rise in the California desert under a fast-track program that dovetails with the state’s own aggressive effort to push development of solar, wind and geothermal power. The far larger one, a 709-megawatt project proposed by Tessera Solar on 6,360 acres in the Imperial Valley, will use “Suncatchers” — reflectors in the shape of radar dishes — to concentrate solar energy and activate a four-cylinder engine to generate electricity.
A 45-megawatt system proposed by Chevron Energy Solutions and featuring arrays of up to 40,500 solar panels will be built on 422 acres of the Lucerne Valley. When complete, the two projects could generate enough energy to power as many as 566,000 homes.
Mr. Salazar is expected to sign off on perhaps five more projects this year; the combined long-term output of all the plants would be four times that of the first two.
“It’s our expectation we will see thousands of megawatts of solar energy sprouting on public lands,” he told reporters.
The announcement, which came shortly after the White House unveiled plans to install the latest generation of solar panels on the roof of its living quarters, reflects a need to enable solar manufacturers to break ground by the end of 2010 so they can share in soon-to-expire grants and loan guarantees for renewable energy.
Federal stimulus grants and federal loan guarantees could underwrite as much as hundreds of millions of dollars or more of the $2.1 billion Imperial Valley plant, said Janette Coates, a Tessera spokeswoman.
The decision also follows a long series of setbacks for climate and energy legislation in Congress. After passage of a House bill last year, efforts to advance a major emissions-reducing bill through the Senate collapsed over the summer for lack of votes linked to fears of a voter backlash.
In addition to the two plants approved Tuesday, projects that are poised to gain approval by the end of the year include BrightSource Energy’s proposed 370-megawatt Ivanpah facility, Tessera’s 850-megawatt Calico project, NextEra’s 250-megawatt Genesis Solar Energy Plant and Solar Millennium’s 1,000-megawatt Blythe project.
The next batch of approvals, Secretary Salazar said, “is something that is not months away.”
But even with federal approval, a major hurdle remains for most of the projects: finding excess capacity on transmission lines in the desert, most of which are fully booked or nearly so. At the moment, capacity exists for about 345 megawatts of the 754 megawatts that would eventually be generated by the two newly approved projects.
The rest would require a new line, like San Diego Gas & Electric’s 123-mile proposed Sunrise Powerlink, which has been approved but faces challenges in federal and state courts.
Mr. Salazar emphasized that the Lucerne Valley and Imperial Valley projects had the support of the Sierra Club, the Natural Resources Defense Council, Defenders of Wildlife and the Wilderness Society.
Both projects were altered to meet environmental objections: they have a smaller footprint than was originally planned and now include greater commitments to mitigate the impact on species like the endangered desert tortoise. Imperial uses minimal water, a scarce resource in the desert. Still, local desert-protection groups remain opposed, and representatives of large environmental groups expressed support in carefully parsed statements.
“These projects were not selected by us,” said Johanna Wald, a senior lawyer with the Natural Resources Defense Council. “They are, as it were, the cards that we were dealt. So we are doing the best that we can by working with the companies, working with the agencies,” to “make them as good as they can be.”
Jim Lyons, who works with renewable energy projects for Defenders of Wildlife, said he supported the Lucerne Valley project. But he said he had some concerns about the impact of the sprawling Imperial Valley solar-reflector project on the landscape, though it has been scaled back from the original 900-megawatt proposal.
“It is smaller, it will go forward in two phases — that certainly is an improvement,” Mr. Lyons said. He said that to achieve such concessions, conservation groups had lodged a formal protest with the Bureau of Land Management, part of the Interior Department.
“It is important for the department to take the lessons learned from these fast-track projects and use that to develop some guidelines,” he added.
The power from the Imperial Valley plant will fulfill its contract for renewable energy made with the San Diego Gas & Electric Company. The power from the Lucerne Valley photovoltaic array is destined for Southern California Edison.
California utilities are currently required to meet a state mandate that they generate 33 percent of their power from renewable sources by 2020.
The announcement of the planned solar panels on the roof at 1600 Pennsylvania Avenue, which would be used to heat water and generate a small amount of electricity, came just a few weeks after the White House rebuffed an environmental organizer who tried to present the White House with a panel from an array installed by President Jimmy Carter in the 1970s. (Ronald Reagan’s administration removed those panels in 1986.)
“This project reflects President Obama’s strong commitment to U.S. leadership in solar energy and the jobs it will create here at home,” Energy Secretary Steven Chu said in a statement. “Deploying solar energy technologies across the country will help America lead the global economy for years to come.”
The Interior Department’s action was delayed by the need for multiple approvals from agencies ranging from the Secret Service to the General Services Administration, officials said.
John M. Broder and Michael D. Shear contributed reporting from Washington.