About Heat Pump Water Heaters

Why a Heat Pump?

Heat pump water heaters are more energy efficient because they use less energy to heat the water compared to natural gas and other electric resistant water heaters. Thanks to heat pump water heating technology, heat pumps expel cold air when they heat your water. This can increase the overall comfort of the surrounding space.  

In addition, heat pump water heaters can improve the air quality and safety in your home. According to the California Air Resources Board, replacing a natural gas water heater with a heat pump water heater helps reduce the amount of carbon monoxide and nitrogen dioxide (N02) that is expelled into your home. This helps improve overall health and reduces safety risks.  

Since Alameda Municipal Power provides 100% clean electricity to your home, you will help reduce the amount of overall greenhouse gas emissions entering your home and the surrounding community when you make the switch to all electric.

How Does a Heat Pump Work?

It helps to think of heat pump water heating as working like your refrigerator, but in reverse.  While a refrigerator pulls heat from inside a box and dumps it into the surrounding room, a stand-alone heat pump water heater pulls heat from the surrounding air and directs it—at a  higher temperature—into the tank of water. Heat pump water heaters are unique because they use electricity to move heat from one place to another instead of generating heat directly. As a result, they can be two to three times more energy efficient than conventional electric resistance water heaters.

Most water heaters have a lifespan of 10 -15 years, and emergency replacement doesn’t usually allow enough time for making the switch. It’s important to plan ahead. When transitioning to a heat pump water heather, there are a few things to consider:

Increased Electric Load

Transitioning appliances to become all electric may require additional capacity for your electrical panel. For example, some heat pump water heater models require about 30amps to operate with a 220/240V breaker. To help offset the cost of panel upgrades, AMP is offering a generous rebate of up to $2500 for customers who are fuel switching. Check out the rebate requirements here.

Space requirements:

Heat pump water heaters are typically installed in a garage, basement, or attic as they are best suited for unconditioned space. They usually take up slightly more space than a conventional gas water heater—700 cubic feet or more is the usually recommendation with 6” clearance above and around. Be sure to confirm space requirements and specifications with your certified installer.

Building Permit:

Replacing your water heater requires a building permit. Please contact the City of Alameda Permit Center for more information.

City Hall Ground Floor
2263 Santa Clara Ave., Room 190
Alameda, Ca 94501


The Bay Area Regional Energy Network (BAYREN) has an approved list called HOME+, which lists approved installers who work in Alameda County for your convenience. Check out their Heat Pump Water Heater Contractor website to get started today.