"Southern California Edison and the maker of steam generators at San Onofre nuclear plant knew about problems with the generators even before they were installed, Boxer and a congressman assert."

"Greenhouse gas emissions from U.S. power plants fell 4.6 percent in 2011 as more generators were switched to cleaner-burning natural gas and renewable sources from coal, according to new data from the Environmental Protection Agency."

"Duke Energy Corp, the biggest power company in the United States, said Tuesday its Progress Energy Florida utility will retire the Crystal River nuclear plant in Florida."

"OSLO -- Plans by Arctic nations to start cooperating over oil spills are vague and fail to define corporate liability for any accidents in an icy region opening up to oil and gas exploration due to global warming, environmentalists said on Monday."

"WASHINGTON -- Critics want a halt to offshore Arctic drilling in the wake of Shell's latest mishap in the waters off Alaska but there's no sign the Obama administration and key members of Congress are backing off their support for drilling in the sensitive region."

California's Monterey Shale formation holds a vast reserve of oil -- on the verge of being tapped -- that could rain riches and controversy on the state.

"Duke Energy will close two of its oldest coal-fired power plants, Riverbend west of Charlotte and Buck in Rowan County in April, two years ahead of schedule."

"CHARLESTON, W.Va. -- Long-term forecasts for coal production in West Virginia and the rest of Central Appalachia continue to show major declines are underway -- and still to come -- for the region's mining industry."

"U.S. Energy Secretary Steven Chu, the Nobel Prize winner who shepherded an effort to help spur a clean energy U.S. economy, will step down after a tenure rocked by the failures of some costly government investments."

"The EPA found serious flaws in two earlier environmental reviews. Soon it will have another opportunity to weigh in, with climate impacts a major concern."

"One of the biggest unknowns in the unfolding Keystone XL debate is the role the U.S. Environmental Protection Agency might play."