The U.S. Department of the Interior released a plan outlining the best sites for solar development, focusing on six Western states.

Formally called the Supplement to the Draft Programmatic Environmental Impact Statement for Solar Energy Development, Interior's plan identifies 17 "solar energy zones" in California, Nevada, New Mexico, Utah, Arizona and Colorado covering 285,000 acres.

It follows a draft plan released last December and comes partly in response to more than 80,000 comments from developers, electric utilities, state government agencies, environmental groups and residents about the then-proposed 24 zones covering 677,000 acres in the six states.

"This Solar PEIS establishes for the first time a blueprint for landscape-level planning that will help facilitate smarter siting of solar energy projects," Interior Secretary Ken Salazar said in a statement Thursday, adding that "it lays a solid foundation for an enduring, sustainable solar energy future for our nation."

The Los Angeles Times reports that this latest draft of the Bureau of Land Management cost the agency more than $13 million to prepare. In addition, as of last year the BLM had spent more than $18 million to more accurately map federal land holdings.

BLM refined or removed zones from last year's draft that involved development obstacles or serious resource conflicts.

Environmental groups were largely supportive of the new plan, with the Defenders of Wildlife, the Wilderness Society, the Natural Resources Defense Council and the Sierra Club calling it "a balanced package intended equally to reflect the needs of the emerging solar industry and the mandate to conserve our nation's precious natural resources" in a joint statement.

The Solar PEIS also establishes a process that will allow development of well-sited projects outside of Solar Energy Zones on an additional 20 million acres of public land.

Interior's announcement comes amid pressure on the Obama administration following the bankruptcy of solar panel company Solyndra, which received a $535 million loan guarantee as part of the president's green energy initiative.

U.S. Energy Secretary Steven Chu, who will testify before a Nov. 17 congressional committee investigating the Solyndra loan, in the Interior news release announcing the Solar PEIS, was quoted as saying, "Tapping the vast potential of solar resources in the Western states will go a long way to diversifying the country's energy portfolio and re-establishing our position as a clean energy leader in a global market worth trillions of dollars in the long term."

Solar power generates about 1-10th of 1 percent of the nation's electricity.