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July 21, 2008

Hawaii to require solar water heaters in new homes

Solar_water_heaterLate last month, Hawaii became the first state in the nation to require solar water heaters in new homes. With few exceptions, solar water heaters will be required in all newly built single-family homes beginning January 1, 2010.

"This solar power legislation is another important step in our long-term plan for energy independence in Hawaii," said Governor Linda Lingle. "In addition to solar, it is critical that we continue to develop innovative energy solutions that capitalize on our natural renewable resource advantages in order to achieve our goal of having 70 percent clean energy in Hawaii by 2030."

The Hawaii law allows builders to install gas-powered water heaters if the home includes another gas appliance. Hawaii's Public Utilities Commission will set standards for solar water heaters, and counties in the state will create implementation procedures. (The illustration above, courtesy of the U.S. Department of Energy, shows an active closed-loop solar water heater.)

Water heating accounts for 15 to 30 percent of a typical household's energy use, according to the DOE. Solar water heaters, while significantly more expensive than their conventional counterparts, can reduce water-heating bills by at least 15 to 25 percent, depending on the efficiency of the system and local climate conditions, the DOE estimates.

A typical two-collector solar water heater costs $5,000 to $7,000, installation included. But after incentives like rebates and tax credits, that cost could drop to $1,400 to $2,100, according to Hawaii's Department of Business, Economic Development and Tourism. (Download the PDF here for more details.)

For Hawaiians, who largely rely on imported fuel and pay among the nation's highest energy prices but enjoy abundant sunshine year-round, solar water heaters could bring long-term financial benefits.—Kristi Wiedemann, Science and Policy Analyst,

Essential information: Read "Save hundreds on energy costs" for more expert advice on slashing your utility bills. Don't miss our reports on thermostats and windows for more information on products that can help you reduce energy consumption.

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