The University of California study comes as state and regional initiatives on climate-change policies have been gathering momentum.

Winter is coming. The economy is in crisis. People are fearful. So why should we hope oil prices don’t fall too far?

Winter is coming. The economy is in crisis. People are fearful. So why should we hope oil prices don’t fall too far?

After months of political assault from Republicans over high gas prices, Democrats are preparing legislation to relax a decades-old ban on oil drilling along much of the nation’s coastline.

Interest for wind turbines small enough to mount on a roof is spreading from coast to coast, even though their installation is hardly ever recouped in electricity savings.

Compared to hotels abroad, the American hospitality industry does not yet have much of a culture of saving resources — but some say changes are coming.

Hybrid models of Detroit’s 5,500-pound S.U.V.’s get better mileage, but consumers have been slow to embrace them.

Hybrid models of Detroit’s 5,500-pound S.U.V.’s get better mileage, but consumers have been slow to embrace them.

Hybrid models of Detroit’s 5,500-pound S.U.V.’s get better mileage, but consumers have been slow to embrace them.

Getting ride of household appliances older than 15 years will probably save you money and their energy costs more environmentally-friendly.