The EPA awarded the most Energy Star ratings in the country last year to Los Angeles, where 262 buildings earned the agency's conservation designation. Energy Star buildings use at least 35% less energy than average buildings and emit 35% less carbon dioxide into the atmosphere.
The sheer size of Los Angeles suggests it would have the most buildings going green, but size wasn't the only factor, said EPA spokeswoman Maura Beard.
"California often leads the country in being progressive in looking at the environment and looking at what they can do," she said.
San Francisco came in second in the country. Rounding out the top 10 in 2008 were Houston; Washington; Dallas-Fort Worth; Chicago; Denver; Minneapolis-St. Paul; Atlanta; and Seattle.
One Los Angeles-area Energy Star-rated building is Providence Little Company of Mary Medical Center San Pedro, where operators pushed for improvements because they knew they could save money while doing the right thing, said Andy Goldschmidt, the hospital's director of facilities.
"We aggressively tried to make this happen," he said.
Steps included upgrading to energy-saving lighting and installing more efficient motors for elevators, fans and other mechanical systems. Among the results was a 2.4% reduction in electricity use, which saved the hospital $90,000 last year.
"We spent $300,000 on this program over the past three years, but we've already made it back," Goldschmidt said.