Inside the Solar Impulse 2, a 5,000-pound plane powered by nothing but sunshine.
It's the Germans' answer to Amazon drones, and it's way, way better.
New rules for oil trains aren't nearly strict enough to prevent disastrous explosions. The most dangerous cars can keep rolling until 2018.
Farmers are buying and selling water up and down the Golden State, and that helps cut waste. If we streamlined and modernized the system, it could do even more.
The billionaire inventor and entrepreneur wants to bring solar power to the masses.
Australia combines two of our favorite things: Solar power and wastewater treatment facilities.
We have some good and some bad reasons for worrying about GMOs — especially when they’re us.
Sarah Fritschner is leading a farm-to-cafeteria movement in Kentucky.
As the U.S. embraces energy efficiency and renewables, economic growth is now rising much faster than greenhouse gas emissions.