The Energy Star program has recently issued its first-ever criteria for water heaters. Beginning Jan. 1, 2009, five categories of residential water heaters will be eligible to bear the Energy Star label: high-performance gas storage, whole-home gas tankless, advanced drop-in or integrated heat pump, solar, and gas condensing water heaters.
Water heaters have not been part of the Energy Star program to date, although they were considered for inclusion in 2003. However, at that time the U.S. Department of Energy (DOE) determined that conventional technologies did not offer sufficient energy savings or market differentiation and that advanced technologies did not meet its performance or reliability expectations, according to to Christina Kielich in DOE’s public affairs office.
According to the U.S. Department of Energy (DOE), water heating is responsible for nearly 17 percent of the nation’s total residential energy consumption; they are the second largest energy consumer behind a home’s heating and cooling equipment. The DOE predicts that by the end of their fifth year in effect, the new water heater criteria will achieve a cumulative energy savings of more than 3.9 billion kilowatt-hours and 270 million therms of natural gas, and will prevent the emission of 4.2 million tons of carbon dioxide.
Each water heater category addressed by Energy Star has a different set of criteria for efficiency, which is expressed as energy factor (EF). A higher EF means a more efficient water heater.
Energy Star criteria for high-performance gas storage water heaters will go into effect in two phases. Beginning Jan. 1, 2009, gas storage water heaters must have a minimum energy factor (EF) of .62, or 6.9 percent more efficient than the federal standard. Phase two goes into effect Sept. 1, 2010 and requires gas storage water heaters to have an EF of .67, or 15.5 percent more efficient than the standard.
Whole-home gas tankless water heater criteria, effective Jan. 1, 2009, will require a minimum EF of .82, a minimum flow of 2.5 gallons per minute at a 77-degree-F rise, or 41.4 percent more efficient than the standard.
Starting Jan. 1, 2009, residential drop-in or integrated heat pump water heaters will be required to have a minimum EF of 2.0, or 121.2 percent more efficient than the standard, and must meet a minimum first-hour rating requirement of 50 gallons per hour.
To qualify for the Energy Star label, a solar water heater must have OG-300 certification from the Solar Rating and Certification Corp., ensuring it has met requirements for performance, reliability, durability, and safety. Solar water heaters also must have a minimum solar fraction (or solar savings fraction) of .50.
Also effective Jan. 1, 2009, residential gas condensing water heaters must have an EF of .80 to qualify for the Energy Star label, making them 37.9 percent more efficient than the standard. They also must achieve a first-hour rating of 67 gallons per hour.
These new additions to the Energy Star program are projected to help homeowners save approximately $780 million in utility costs.
