"Oil prices sank again on Monday, giving consumers more of a break and causing a split among OPEC leaders about what action should be taken, if any, to halt the slide."

"At the annual SXSW Eco, a conference in Austin, Texas, you'll find a lot of serious discussion of the rapid decline of the Earth's ecosystems."

"A little-known federal office that has long been a thorn in the side of regulatory reform advocates is taking center stage in the battle over a controversial water regulation."

"Toymaker will not renew current multimillion pound deal, that sees Shell-branded Lego sets sold at petrol stations, following a viral video against Arctic drilling by the green group"

"For a variety of reasons -- whether it be mitigating climate change, enhancing security, increasing economic incentives or even improving the health of indoor living -- countries around the world have been investing in ways to boost energy efficiency. Worldwide, that market of cutting back on energy waste is growing and is now worth at least $310 billion, reports the International Energy Agency."

"The share-price boom at U.S. energy firms has gone bust, due to slumping global growth and tumbling crude prices."

"What ties America's second-biggest energy company, ConocoPhillips Co., to a small Houston-based shale driller, Halcón Resources Corp.? They had some of the worst carbon pollution rates among their peers in 2012."

The Chesapeake Bay region would reap an additional $22.5 billion a year from improved hurricane protection, crab and fish production and climate stability if the Obama administration's contested plan to clean up the watershed proceeds, an environmental group says."