Water Heating


Keep water hot and use less energy with Heat Pump Water Heaters.

Idrew-wyman-hpwh.jpgf yours is one of the 750,000+ homes in Maine, New Hampshire, and Massachusetts that heats domestic hot water (DHW) with an oil-fired boiler, it’s hard to ignore the roar in your basement as the boiler fires up to make hot water while sunshine pours down onto your roof, especially in the summer.

This is a terribly inefficient (and therefore environmentally harmful) way to make hot water, but the good news is you can save hundreds of gallons of oil per year by switching to a heat pump water heater, and powering it with solar.

Using the same refrigerant process as an air source heat pump, heat pump water heaters efficiently leverage the ambient air of your home for water heating.

Heat Pump Water Heater Federal Tax Credit

Starting in January 2023, you can receive a 30% tax credit for heat pump water heaters, capped at $2,000 per year. The credit resets each tax year, effectively becoming available again for additional projects. 

Additionally, there are further credits for low-moderate-income households, thanks to the High-Efficiency Electric Home Rebate Act (HEEHRA). Home Energy Rebates under HEEHRA are not yet available, but we expect New England states to launch programs available to their residents in 2024.

For low-income households (under 80% of Area Median Income), HEEHRA covers 100% of your heat pump water heater costs up to $1,750. For moderate-income households (between 80% and 150% of Area Median Income), HEEHRA covers 50% of your heat pump water heater costs up to $1,750.

Total HEEHRA discounts across all qualified electrification projects are capped at $14,000.


  1. Instead of making heat, heat pump water heaters simply move it from one place to another, which is much more efficient than conventional electric water heaters, or other ways to make hot water.
  2. They produce hot water 200-600% more efficiently than resistive electric tanks.
  3. While they move heat, they also help dehumidify the space around them.
  4. They are highly insulated, meaning the energy you do use for hot water is not wasted in ‘standby losses’ as the tank sits idle.
  5. They are available in large tank sizes, which means that you can easily meet the needs of a 4+ person household with a heat pump water heater.

All of this efficiency translates to savings, with bonus basement dehumidifying! Plus, many states offer cash rebates for installing them.

Due to its much lower electric consumption, a heat pump water heater needs only about 1/3 of the PV modules to generate the electricity for domestic hot water compared to a resistive electric tank.

Heat Pump Water Heater with Solar PV

  • Very simple and straightforward installation, can usually be done same day as Solar PV install
  • Excellent balance of efficiency and cost
  • Long lasting systems come with reliable 25-year PV warranty and a 10-year water heater warranty

Typical Yearly Water Heating Costs for a Family of 4*

Heat pump water heater powered by grid $413
Heat pump water heater powered by solar $165 **
Electric water heater powered by grid $1,238
Electric water heater powered by solar $495
On demand electric powered by grid $1,022
On demand electric powered by solar $408
Oil boiler (oil at $1.99/gal) $647 ***
Oil boiler (oil at $2.99/gal) $971
Propane water tank $1,539
On demand (tankless) propane $432
 
Assumptions:
  • * Load calculations use 65 gallons a day of hot water for a 4-person household or 16.25 gallons per person. To calculate consumption for a different number of people, or different consumption, just do the math!
  • ** Grid electricity priced at 25 cents per kilowatt-hour, solar at 10 cents per kilowatt-hour (roughly the 20-yr cost of solar PV for an average 5kw system), propane at $3.50/gallon.
  • *** Oil and propane tanks calculated at ‘average’ efficiencies. There are a few different ways of using oil and propane to heat domestic hot water (direct fired, indirect tank, tankless), this chart uses an average.