WASHINGTON - The U.S. Department of Energy (DOE) has announced new Energy Star® criteria for water heaters, the first in the history of the program. According to DOE projections, by the end of the fifth year in effect, the new water heater criteria are expected to save Americans approximately $780 million in utility costs, avoid 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. Water heating currently represents up to 17 percent of national residential energy consumption, making it the third largest energy user in homes, behind HVAC and kitchen appliances.

DOE Assistant Secretary for Energy Efficiency and Renewable Energy Andy Karsner said, “Expansion of the Energy Star program to include water heaters will give Americans yet another way to more efficiently use energy in their homes.”

For the first time, the following five categories of residential water heaters will be eligible for an Energy Star label: high-performance gas storage, whole-home gas tankless, advanced drop-in or integrated heat pump, solar, and gas condensing.

The new criteria for high-performance gas storage water heaters will take effect in two phases. The first phase goes into effect Jan. 1, 2009, and requires gas storage water heaters to have a minimum Energy Factor (EF) of 0.62 - or they must be 6.9 percent more efficient than the federal standard. Energy Factor is a measurement of relative energy efficiency for a water heater; the higher the Energy Factor, the more energy efficient the water heater. A 50-gallon high-performance gas storage water heater which meets the new Energy Star criteria, for example, is estimated to yield annual savings of 7.3 percent and save $26 using the national average gas rate. Effective Sept. 1, 2010, phase two requires the EF to increase to 0.67 - or 15.5 percent more efficient than the federal standard, resulting in annual savings of 14 percent and $51 for a single high-performance gas storage water heater.

Taking effect Jan. 1, 2009, whole-home gas tankless water heaters which carry the Energy Star label must have a minimum EF of 0.82, minimum gallons-per-minute flow of 2.5 at a 77°F rise, or be 41.4 percent more efficient than the current federal standard. A whole-home gas tankless water heater with a 0.82 EF is expected to achieve a 30 percent reduction in energy use and save a consumer approximately $108 in annual energy costs compared to a typical gas storage water heater.

Energy Star criteria for residential drop-in or integrated heat pump water heaters require a minimum EF of 2.0 or must be 121.2 percent more efficient than the federal standard, and a minimum First-Hour Rating requirement of 50 gallons-per-hour, effective Jan. 1, 2009. Under these criteria, a heat pump water heater is expected to save consumers nearly 55 percent in energy use and yield annual energy savings of approximately $277 compared to a typical electric resistance water heater.

Effective Jan. 1, 2009, solar water heaters must have at a minimum Solar Fraction of 0.50 and OG-300 certification from the Solar Rating and Certification Corporation (SRCC) in order to carry the Energy Star label. The SRCC is a third-party organization that rates solar water heater systems. By earning the OG-300 rating, solar water heaters have met certain performance, durability, reliability, and safety requirements set by the SRCC. An OG-300 certified solar water heater with a 0.50 Solar Fraction and a 50-gallon electric storage auxiliary water heater would achieve a Solar Energy Factor of 1.8, saving 50 percent in energy use and annual savings of $180, compared to a typical electric storage water heater.

To qualify for the Energy Star label, residential gas condensing water heaters must have an EF of 0.80, which is 37.9 percent more efficient than the federal standard, and a minimum First-Hour Rating of 67 gallons-per-hour. Under these criteria, taking effect Jan. 1, 2009, a 50-gallon water heater would save nearly 30 percent in energy consumption and result in $102 in annual energy savings compared to the conventional typical gas storage water heater.

For more information about the Energy Star program, visit www.energystar.gov.

Publication date:04/21/2008