The familiar yellow EnergyGuide labels seen on home appliances will be attached to televisions in stores, giving consumers a better idea of how TVs stack up on power consumption.

The Federal Trade Commission yesterday announced that televisions manufactured after May 10, 2011 will need to have an EnergyGuide label, which are now used for white goods such as dishwashers and refrigerators.

Consumers will be able to get an estimate of the cost to power a TV for a year and how those costs compare to other TVs of a similar size. The labels must be displayed on the front of the TV. Starting in July next year, Web sites will need to display an image of the label online.

"Unlike many years ago, before flat screens and plasma, today's televisions vary widely in the amount of energy they use," said FTC Chairman Jon Leibowitz. "By comparing information on the EnergyGuide labels, consumers will be able to make better-informed decisions."

A sample EnergyGuide label for TVs which shows estimated annual energy use based on five hours of use a day and the national average price for electricity.

With more households buying larger, flat-screen TVs to replace CRTs, power consumption from TVs can in many cases increase. (See CNET's TV energy efficiency guide here). Electronics, such as TVs, computers, and DVRs, are the fastest growing source of energy consumption in homes, according to the Natural Resources Defense Council.

The FTC was tasked with created the EnergyGuide label for consumer electronics in the 2007 federal energy law.

Industry group the Consumer Electronics Association (CEA) which fought implementation of California's TV efficiency mandates, lauded the labels. "CEA has long supported efforts to provide consumers with more information about the energy use of the electronics they purchase, and we look forward to working with the FTC as it considers similar measures for other product categories."

Senior scientist at the NRDC, Noah Horowitz, said that the labels for TVs are particularly important because one TV could consume double another one. He said the FTC did a good job on the labels and encouraged them to take on other electronics products.

"It's really important to get this information in front of consumers who want to know what they are buying as they try to lower their electric bill," Horowitz said.