Energy Star Expands to Home Water Heaters

The U.S. Department of Energy 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 heating and cooling, and kitchen appliances.

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-efficiency and 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.

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 degrees Fahrenheit rise, or be 41.4 percent more efficient than the current federal standard.

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.

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 in order to carry the label.

To qualify for the 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 January 1, 2009, a fifty-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.