In his most extensive public comments to date on the subject, the president says that Keystone would create few jobs and raise gas prices for Americans.
As more government land is earmarked for solar and other renewable energy projects, some environmental activists in the West are not happy.
Two incompatible electric-vehicle charging systems are fighting for dominance, like a replay of the '80s-era battle between VHS and Betamax.
The fire is out at the gas-drilling rig that caught fire in the Gulf of Mexico this week, but a debate about drilling regulations has sparked back to life.
When Halliburton's computer simulations showed it could have shared blame for the epic blowout and oil spill, the company destroyed the results.
Eight in 10 young voters support Obama's climate plan, and three-quarters describe climate deniers as "ignorant," "out of touch," or "crazy."
A cliff of Antarctic ice is wasting away 10 times faster than it had in recent geological history, a new study says, and that could be bad news for the whole continent.
Transocean has been refusing to hand over documents to the federal government, but now a federal appeals court says it must.
After air pollution reached sickening new heights earlier this year, the government now says it will spend $277 billion to tackle the problem.
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