National (U.S.)

A well-working market that prices conservation as a source of electrical energy faces serious legal challenges from power producers.

"DES MOINES, Iowa — Christmas tree likely will cost a little more this year, and growers like John Tillman say it's about time."

"President Obama could leave office with the most aggressive, far-reaching environmental legacy of any occupant of the White House. Yet it is very possible that not a single major environmental law will have passed during his two terms in Washington."

"A ProPublica analysis of federal government data adds new details to what’s known about the routes taken by trains carrying crude oil. Local governments are often unaware of the potential dangers they face."

"The U.S. Supreme Court on Tuesday agreed to weigh a challenge by industry groups and some states to an Obama administration regulation intended to limit emissions of mercury and other hazardous pollutants mainly from coal-fired power plants."

"The Obama administration is expected to release on Wednesday a contentious and long-delayed environmental regulation to curb emissions of ozone, a smog-causing pollutant linked to asthma, heart disease and premature death."

"If you're heading to the airport to fly to the East Coast for Thanksgiving, expect delays of three to six hours."

"The Interior Department is scrambling to meet a September 2015 deadline to avert an Endangered Species Act listing for the greater sage grouse -- what some Westerners warn would be a political and economic disaster."

"Lake Powell is at historic lows, offering kayakers new channels to explore but raising the alarm about water."

"As biotech masterminds and venture capitalists scramble to hatch a new generation of environmentally friendly fuels that can help power the average gasoline-burning car, they are confronting an unexpected obstacle: the White House."