Ground-source Heat Pumps
Use the earth’s constant temperature.

Why install a ground-source heat pump?

A ground-source heat pump takes advantage of a renewable resource: the heat underground and in underground water.

Ground-source heat pumps are among the most energy efficient of all heating and cooling systems. While they’ve traditionally cost more than other systems, improvements in installation techniques and processes have made them an attractive alternative, and prices are coming down.

Good applications include homes that:

  • Need energy-efficient heating and cooling

  • Have access to ground water or surface water

  • Have forced-air or radiant hydronic wall registers

  • Aren’t practical locations for above-ground AC or outdoor heat pumps

  • Are being built and will enable radiant hydronic piping in the floor or ceiling


  • Use up to 72 percent less energy per year than electric resistance heating with standard air conditioning*

  • Efficiencies of 300 to 600 percent on the coldest winter nights, compared to 240 percent efficiency for a standard air-source heat pump*

  • Essentially “free” hot water when cooling is needed.

  • Zero emissions

  • Embraced by LEED™ and other green building organizations

How a ground-source heat pump works

A geothermal heat pump uses the constant below-ground temperature of soil or water to heat and cool your home. In winter it pulls heat from the earth or water (1) and brings it inside, using a heat exchanger (2). In summer, the process reverses to cool your home. Some systems also supply hot water, further increasing energy efficiency.

Hire an experienced contractor

These installations are complex, so it’s critical to use a qualified licensed contractor with experience in ground-source heat pump installations. Some PGE-approved contractors are expert at installing ground-source heat pumps. The Oregon Department of Energy also maintains a statewide listing of tax-credit certified technicians.

Purchasing advice

The U.S. Department of Energy website has extensive information on how to buy an energy-efficient, ground-source heat pump PGE.

Discounts, Incentives and Credits**

On qualifying, premium-efficiency heat pumps

Get a $200 instant PGE discount when you have PGE-approved contractors install an energy-efficient heat pump, or upgrade from an older, less efficient heat pump.

  • Heat pumps must be rated at a minimum ARI certified 8.2HSPF (heating efficiency) and 14 SEER (cooling efficiency).

  • The system must meet PGE installation specifications. The PGE-approved contractor can also help you select the right size and model.

You may also qualify for an up to $900 Oregon tax credit PGE and a 30 percent federal energy tax credit PGE. The federal tax credit is 30 percent of installed cost, with no upper limit.

Ask your PGE-approved contractor about generous manufacturers’ rebates that may be available.

*Source: U.S. Department of Energy

**Incentives and tax credits are subject to change. Make sure your heat pump meets all qualifying criteria by consulting with a tax advisor and visiting PGE.

Need help? Just ask!

The PGE Energy Experts can discuss your eligibility for rebates, tax credits and incentives. Email or call them at 503-612-3500 or 800-722-9287.