Heat water with heat that is already in your home.
A heat pump water heater uses a small compressor and fan to move heat from the surrounding air into a storage tank. The result is efficient hot water, lower electric use, and an appliance that pairs naturally with rooftop solar.
Lower operating cost. Less energy. A better fit for an electric home.
Water heating is one of a home's larger energy loads. Instead of making heat directly with resistance elements, a heat pump moves existing heat—similar to the technology in a refrigerator, but in reverse.
Reduce electricity use
Heat pump operation can dramatically reduce the electricity needed for hot water compared with a conventional electric tank. Hybrid units can still use resistance elements when hot-water demand is unusually high.
Make solar go farther
Because the water heater is an efficient electric load, solar can directly offset much of its annual consumption. Smart scheduling can also shift water heating toward sunny daytime hours.
Lower environmental impact
Using less electricity reduces the energy required to heat water. Replacing combustion water heating also removes on-site fuel burning, while the environmental benefit grows as the electric grid gets cleaner.
What could a heat pump water heater save?
The most useful payback comparison is the incremental cost of the heat pump model versus the conventional water heater you would otherwise install. Adjust the assumptions to match your home.
ENERGY STAR's published example for a four-person household is about $550/year in savings at $0.146/kWh, with 3,760 kWh of annual savings compared with a standard electric water heater. Actual performance depends on hot-water use, operating mode, installation location, electric rate and equipment.
A small amount of solar can cover a surprisingly large share of your hot water.
A representative efficient 65-gallon heat pump water heater can use roughly 1,100–1,200 kWh per year under a standard draw profile. In Wisconsin, a well-sited 440-watt panel may produce roughly 500–550 kWh per year, so about 2–3 modern panels can offset the water heater's annual electricity use.
Important: this is an annual-energy comparison, not a claim that the water heater runs directly from those panels at every moment. Grid-connected solar production and water-heating demand occur at different times.
panels to offset annual HPWH use
Each panel is estimated to produce about 550 kWh/year. Exact output depends on roof direction, tilt, shading, snow, equipment and weather.
Think “efficient water heater + small dehumidifying cooling effect.”
Manufacturers commonly call for access to roughly this much free air, or appropriate venting. ENERGY STAR gives an 8 × 12 × 8 ft room as an example of adequate volume.
ENERGY STAR Version 5.0 products are limited to less than 55 dBA. Some models are around 45 dBA—similar to a quiet dishwasher.
While actively heating water, the unit can reject this amount of cooling into the surrounding space and also remove moisture from the air.
What homeowners usually want to know first.
What does a 65-gallon heat pump water heater typically cost?
For planning purposes, we use an average installed price of about $4,000 for a 65-gallon system. Actual cost depends on the equipment selected, plumbing changes, electrical requirements, condensate routing and site conditions.
How loud are heat pump water heaters?
They contain a fan and compressor, so they are not silent. ENERGY STAR Version 5.0 models are rated below 55 dBA, roughly background-conversation territory, and some units are closer to 45 dBA. A basement, utility room or other space away from bedrooms is generally a better location than a quiet living area.
How much room do they need?
Manufacturer requirements vary, but ENERGY STAR notes common minimum free-air requirements of approximately 450 or 700 cubic feet. If the unit must be installed in a small closet, transfer grilles, a louvered door or approved ducting may be used depending on the model and installation instructions.
Will it make my basement cold?
It will cool and dehumidify the room while the heat pump is operating. ENERGY STAR guidance cites roughly 2,500–5,000 BTU/h of cooling during operation. In summer this can be a welcome side effect; in a Wisconsin winter it creates a small additional load on the home's heating system. Basements are still commonly considered strong installation locations.
Does it dehumidify the room?
Yes. Moisture condenses as the unit extracts heat from room air, so the discharge air is cooler and drier. The unit therefore needs a condensate drain or, when gravity drainage is impractical, an appropriate condensate pump.
Will a 65-gallon tank keep up with a family?
Often, yes, but tank size should be selected around household size and peak hot-water demand. Larger tanks can improve efficiency because they let the heat pump do more of the work and reduce reliance on the faster but less-efficient resistance elements during heavy use.
Why does a heat pump water heater pair so well with solar?
It converts a major household energy use into a highly efficient electric load. For a representative 65-gallon unit, annual use can be in the neighborhood of 1,100–1,200 kWh, which is roughly the annual output of 2–3 well-sited modern solar panels in Wisconsin. Smart controls can also help move water heating toward daytime solar production.
Does it need a special electrical circuit?
Many whole-family hybrid heat pump water heaters use a 208/240-volt circuit, often with a 30-amp circuit, although lower-amperage and 120-volt products also exist. The exact requirement must follow the selected manufacturer's installation instructions and applicable electrical code.
We can look at the water heater, electrical service and solar together.
A combined review makes it easier to choose the right tank size, electrical approach, installation location and solar offset.
This page uses general planning estimates, not a site-specific engineering or utility-savings guarantee. Key technical references: U.S. Department of Energy guidance on heat pump water heater efficiency; ENERGY STAR heat pump water heater savings and design guidance; and PVWatts/National Laboratory solar-production methodology. Product image photography shown above is sourced from ENERGY STAR / EPA.
ENERGY STAR: Benefits & Savings · ENERGY STAR: Design Considerations · DOE: Heat Pump Water Heaters · PVWatts Calculator