Water heaters have finally joined the Energy Star party.

This spring, the federal government issued the criteria that water heaters must meet to obtain the Energy Star label. These new standards, which take effect beginning in 2009, are expected to save American consumers approximately $780 million in utility costs by the fifth year of the standard’s use.

(As many builders know, Energy Star is a joint EPA/DOE program designed to save money and protect the environment through energy-efficient products and practices. The program covers a wide variety of building products such as appliances, HVAC equipment, and lighting as well as consumer products such as home electronics.)

The DOE says criteria will cover five categories of residential water heaters: high-performance gas storage, whole-house gas tankless, advanced drop-in or integrated heat pump, solar, and gas condensing units.

Standards for high-efficiency and high-performance gas storage water heaters will take effect in two phases—Jan. 1, 2009, and Sept. 1, 2010. Standards for all other categories are effective Jan. 1, 2009.

“It is our intent to accelerate the provision of high-performance gas storage water heaters in the market by establishing a goal for manufacturers to meet,” Energy Star Products Manager Richard H. Karney said.

The DOE says the new water heater standards will eliminate 4.2 million tons of carbon dioxide emissions “and achieve cumulative energy savings of more than 3.9 billion kilowatt-hours and 270 million therms of natural gas,” according to an agency release.

Homeowners are expected to benefit as well. Water heating is the third-largest expense in the home (after air conditioning and major appliances) and accounts for 14 percent to 25 percent of the home’s operating costs. Domestic water heating represents up to 17 percent of national residential energy consumption.

For more specific information on efficiency requirements for hot water tanks, visit www.energystar.gov.

Nigel Maynard is senior editor for BUILDER magazine.