A unique device turns excess water pressure from reservoirs, water treatment plants and factories into electricity.

If you use more as you pay less, the planet keeps getting hotter

Solar power has long had a reputation for being expensive, but the falling costs of making panels could change that

Antarctica is so vast that the pictures give you no sense of scale. The pencil-thin line across the satellite image of Pine Island Glacier (above) is actually more than 18 miles long, 800 feet across in places, and 180 feet deep. And it’s growing. In...

Forecasters are perplexed by the mild weather across the U.S., and they expect more of the same. Many residents are delighted, but ski areas and other season-oriented businesses are struggling.Birds were singing. Insects were buzzing. And a large skunk suddenly appeared in the road in front of meteorologist Paul Pastelok as he drove to work in rural Pennsylvania.

The relatively clean gas is replacing dirty coal-fired power plants. That's good news for the environment. But in the long run, cheap natural gas might delay the transition to even cleaner sources of energy, such as wind and solar power.

Climate scientists are protesting the Wall Street Journal's publication of a letter from climate skeptics with mostly non-climate backgrounds.

More than a million green turtle eggs were laid last year on one of the Turtle Islands in the Philippines.

The fact that the climate is already changing, and will continue to change, means we need to start adapting agriculture to a warmer world immediately

Clouds of slow-moving charged particles reach from the top of Earth's atmosphere to a quarter of the distance to the moon, new data show.

Advances are opening solar to the 1.3 billion people who don't have access to grid electricity.

Even with California's volatile weather, where exceptions are the rule, the season has been the driest in 30 years. Without snow, hotels offer rock climbing and archery to frustrated skiers.Reporting from Yosemite National Park -- Winter in the high country is usually a season of icy quiet. Birds leave, bears hibernate, and only a few hardy people on skis or snowshoes pass through en route to snow-covered granite domes.

Gardeners: Take heed. An updated plant map shows that the United States is getting warmer. That means spring planting may come earlier and some plants can tolerate new northern latitudes.

The president is promoting the sale of new oil and gas drilling leases in the Gulf of Mexico and the promise of cars running on natural gas in two key states for his re-election campaign, Nevada and Colorado. The push comes days after he drew sharp Republican criticism for rejecting the Keystone XL pipeline from Canada.

Astrowatt's wafer-making method could mean cheaper solar power. Today, most solar cells are made with a process that turns almost half of the raw material—highly refined and processed crystalline silicon—into sawdust. A new process developed by startup Astrowatt aims to eliminate most of this waste while making solar cells more efficient.