The White House is finally on the solar grid, in response to prodding by environmentalists and nearly four years after then-Energy Secretary Steven Chu pledged that solar panels and a solar water heater would be installed on the historic building's roof.
The American-made panels are converting sunlight into energy at the first family's residence as part of President Barack Obama's "commitment to lead by example to increase the use of clean energy in the U.S.," said Matt Lehrich, a White House spokesman.
The long-awaited announcement came as Obama on Friday touted a raft of administration initiatives aimed at boosting the use of alternative energy, as part of his alert on climate change - a message that resounds with his liberal base but faces opposition from congressional Republicans, who the president said Friday were "wasting time" arguing about what he said was a settled debate.
"Climate change is real and we have to act now," Obama said at a California Wal-Mart as he praised the company for embracing solar energy. He sought to counter Republican criticism that addressing climate change will cost jobs, saying "there are cost-effective ways to tackle climate change and create jobs at the same time."
He suggested a growing consensus that climate change is a threat: "Unfortunately, inside of Washington we've still got some climate deniers who shout loud, but they're wasting everybody's time on a settled debate," he said.
Senate Minority Leader Mitch McConnell, R-Ky., said that if Obama were serious about creating jobs he'd change course.
"If the president really wanted to be helpful and move America toward energy independence, he'd do things like approving the Keystone pipeline, stopping the war on coal," McConnell said.
The panels on the White House are a part of a plan to improve the energy efficiency of the building and "demonstrate that historic buildings can incorporate solar energy and energy efficiency upgrades," Lehrich said.
It's estimated that the upgrades will pay for themselves in energy savings over the next eight years - if the next president doesn't remove them. President Jimmy Carter installed 32 panels in 1979, when an Arab oil embargo spiked fuel prices, but President Ronald Reagan removed them in 1986 when the roof was resurfaced.
President George W. Bush had some installed on a maintenance building and on the president's cabana to heat water for the outdoor White House pool, and environmentalists have been pressing Obama to go even further.
"The point is that the president is wanting to highlight that solar can go anywhere, even on the people's house," said Amit Ronen, who directs the George Washington University Solar Institute.
As any homeowner knows, renovations can take time, and the White House isn't the average house. The delays have been attributed to a mix of politics, bureaucracy, security and the historical nature of the building.
Chu promised in October 2010 that the panels would go up on the White House.
"As we move toward a clean energy economy, the White House will lead by example," he said. "It's been a long time since we've had them up there."
By the next year, the Energy Department said the project was mired in the "competitive procurement process."
Solar enthusiasts note that homeowners are unlikely to encounter the same delays. Experienced crews can install panels on two standard houses in a day, though many homes take longer.
The retrofit includes energy-saving equipment such as updated building controls and variable-speed fans, as well as 6.3 kilowatts of solar generation, Lehrich said.
A White House video promoting the panels features new Energy Secretary Ernest Moniz, who proclaims himself "very bullish on the future of solar energy as a key part of our clean energy future."
The size of the array of panels used is about the same as that for the average American house, White House usher James Doherty says in the video, noting that because of security concerns, the entire roof couldn't be covered.
At a Mountain View, Calif., Wal-Mart that has solar panels atop its roof, Obama announced more than 300 private- and public-sector solar power and energy efficiency commitments that the White House says will create jobs and cut carbon pollution.
And he announced a Department of Energy program to increase the use of high-efficiency outdoor lighting, replacing more than 500,000 lighting poles in towns and cities, starting with Detroit, the Kansas City, Mo., metro area, West Palm Beach, Fla., Little Rock, Ark., and Huntington Beach, Calif.
He said the Department of Energy's Solar Instructor Training program would support training programs at community colleges to help 50,000 students enter the solar industry by 2020.
Obama also said he had ordered an additional $2 billion goal in federal energy efficiency upgrades to federal buildings over the next three years.
Explore further: Sun rises on solar panels on White House roof