Heat pump water heaters, sometimes called hybrid water heaters, use technology similar to heat pumps. Instead of heating air, they heat water.
Water heating can chew up nearly 15 percent of a household’s energy spending and ranks as the second-largest consumer of electricity in homes after heating and cooling.
A HPWH operates like a refrigerator running in reverse. A refrigerator pulls heat from inside its cooling area and moves it into the air in a room. A heat pump water heater pulls the heat out of the air, usually the air inside your garage, heats it up more, then moves it into the hot water tank.
Like many new technologies, heat pump systems require a higher upfront investment. “They can run from less than $1,000 to more than $2,000 not including installation,” said DuWayne Dunham, energy counselor for Clark Public Utilities. “But they are very efficient compared to electric or gas water heaters and may lower your utility bill several dollars a month. Which adds up over time.”
Some high-efficiency models of HPWHs can be installed by the homeowner, but all require a Clark County permit.HPWHs are almost 2½ times more efficient than electric ones. Two years ago, the Electric Power Research Institute did a study on heat pump water heaters that involved five residents of Clark County. The HPWHs were installed and monitored for more than a year.
“The study showed heat pump water heaters save about 3 kilowatt hours per day for a yearly savings of 1,095 kilowatt hours over an electric water heater,” Dunham said.
None of us pay much attention to our water heaters until they break. When one does, we want our hot water for showers and dishwashers back in 24 hours or less. That doesn’t leave much time for researching alternatives.
Fortunately, Ridgefield resident Tom O’Neal took the time to research HPWHs as soon as the electric water heater in his garage showed signs of failing early last fall. When it finally died, he replaced it with an $1,100, 50-gallon heat pump water heater and expects to recoup his investment within four years.
Current utility rebates for HPWHs, combined with available manufacturer rebates, can significantly reduce the cost for eligible homeowners. Utility rebates require that the HPWH replace an existing electric water heater and vary based on efficiency.
Beside garages, good locations for HPWHs include utility rooms and basements. During normal operating conditions, the HPWH produces cool exhaust air and can sound like a window air conditioner for about four hours each day.
Some resources for finding out more about HPWHs are the Clark Public Utilities website as well as smartwaterheat.org. Using these, you can find lists of the manufacturers offering rebates and can search for a contractor in your area by ZIP code.The utility offers a $300 (Tier I) or a $500 (Tier II) rebate on HPWHs.
To find out which units qualify for these rebates, go to the utility’s website: www.clarkpublicutilities.com/index.cfm/your-home/appliances/water-heaters/heat-pump-water-heater.
The utility website leads you to information on the Bonneville Power Administration website for a list of models that qualify for a rebate and to smartwaterheater.org if you’re looking for a certified contractor.
Energy Adviser is written by Clark Public Utilities. Send questions to ecod@clarkpud.com or to Energy Adviser, c/o Clark Public Utilities, P.O. Box 8900, Vancouver, WA 98668.