On a unanimous vote, the California Energy Commission required all new televisions up to 58 inches to be more energy efficient, beginning in 2011. The requirement will be tougher in 2013, with only a quarter of all TVs currently on the market meeting that standard.
The commission estimates that TVs account for about 10 percent of a home's electricity use. The concern is that the energy draw will rise by as much as 8 percent a year as consumers buy larger televisions, add more to their homes and watch them longer.
Commissioners say energy efficiency standards are the cheapest and easiest way to save electricity.
"We have every confidence this industry will be able to meet the rule and then some," Energy Commissioner Julia Levin said. "It will save consumers money, it will help protect public health, and it will spark innovation."
TVs larger than 58 inches, which account for no more than 3 percent of the market, would not be covered by the rule, a concession to independent retailers that sell high-end home-theater TVs. The commission is expected to regulate them in the future.
Environmental groups supported the tougher standards and hoped they will prompt manufacturers to make new energy-efficient models for the rest of the nation. They said the rules would cut California's power bill by $1 billion a year, avoiding the need to build a 500-megawatt power plant.
Some manufacturers said implementing a power standard will cripple innovation, limit consumer choice and harm California retailers because consumers could simply buy TVs out of state or order them online.
Industry representatives also have said the standards would force manufacturers to make televisions that have poorer picture quality and fewer features than those sold elsewhere in the U.S.
As an example of the new standards, all new 42-inch television sets must use less than 183 watts by 2011 and less than 116 watts by 2013. That's considerably more efficient than flat-screen TVs placed on the market in recent years.
A 42-inch Hitachi plasma TV sold in 2007 uses 313 watts slightly more than the power consumed by five 60-watt light bulbs while a 42-inch Sharp Liquid-crystal display, or LCD, TV draws 232 watts, according to Energy Commission research. LCDs now account for about 90 percent of the 4 million TVs sold in California annually.
Some televisions already meet the early standards imposed under the rule approved Wednesday. About three-quarters of the TVs more than 1,050 models sold today comply with the 2011 California standards, and more than 300 comply with the 2013 standard, according to the Energy Commission.
California has previously led the nation in setting efficiency requirements for dishwashers, washing machines and other household appliances as a way to address the state's growing electricity demand.
Utilities and environmental groups say the TV standards should head off steep increases in home electricity use and rising electric bills.
Each energy-efficient TV would save a household roughly $30 a year in lowered electricity costs. If all 35 million TVs watched in the state were replaced with more efficient sets, Californians would save $8.1 billion over 10 years, according to the Energy Commission report.
Televisions account for about 2 percent of California's overall electricity use. Requiring them to be more energy efficient would save enough electricity to power 864,000 single-family homes a year in California by 2023. That's enough for Anaheim, Burbank, Glendale and Palo Alto combined.
The electricity savings could help California meet the goals of its 2006 global warming law, which calls for the state to cut greenhouse gases 25 percent by 2020.
Gov. Arnold Schwarzenegger praised the commission's action as another signal of California's leadership on environmental matters. He noted that the state's per-capita electricity consumption has remained flat over the last three decades while energy consumption nationwide has increased.
"I applaud the commission for its hard work to enact these and other cost-effective energy efficiency standards that are not only great for the environment, but also good for consumers," the governor said in a statement.