Heat Pump Efficiency: The Heating Season Performance Factor


Heat pumps aren’t just for heating and cooling homes in mild climates anymore! Advances in heat pump technology have created a legitimate heating alternative for colder regions where temperatures may drop below freezing.1 Today’s heat pumps are now being installed from Alaska to Florida.2

A heat pump is considered an energy-efficient heating option because it moves heat rather than converting it from fuel. When a thermostat calls for heat, the refrigerant in your heat pump’s coil extracts heat energy from the cold outdoor air. Even if it’s 32°F outside, there is enough heat energy from the outdoor air to heat your home.

A heat pump’s reversed refrigeration cycle may allow properly installed heat pumps to deliver up to three times as much heat as the electrical energy used to operate it.3 This may make a heat pump a great energy-efficient option for your home.

How Heat Pump Heating Efficiency is Measured?

A heat pump’s heating efficiency rating is indicated by the Heating Season Performance Factor or HSPF number. That number represents the calculation of the heat pump’s total seasonal heat output, including the supplementary electric heat, as compared to the total electricity used during the same period.4 The HSPF is a heat pump’s heating version of SEER or Seasonal Energy Efficiency Ratio.

HSPF measures heat pump efficiency in heating mode
SEER measures heat pump efficiency in cooling mode

HSPF and Efficiency


Typically, the higher the HSPF number, the more efficient the heating performance of your heat pump.5 The U.S. Department of Energy raised the minimum energy efficiency standard for heat pumps in 2015 to 8.2 HSPF nationwide. That’s great news for homeowners in the market for a new heat pump — especially if your current heat pump’s HSPF rating is lower than the current standard.

Energy-efficient features, such as variable speed fans and variable speed compressors have ushered in a new era of heat pumps and heating systems. These features offer increased energy efficiency benefits when compared to some older or base models, as well as help keep your budget in check and greatly improve your overall comfort level in your home.

Today’s high-efficiency heat pumps can boast HSPF ratings of 9 or higher, which may provide significant savings on monthly heating bills when compared to a lower HSPF model operating under the same conditions. However, there is more to heating efficiency than just a heat pump’s HSPF number. Other factors that may significantly impact the performance of a heat pump. These often include:6 

  • Air duct air leaks
  • Part-load efficiency
  • Proper equipment sizing
  • Thermostat or control system settings
  • Climatic conditions

If you are looking to save even more on monthly heating bills, the opportunity for additional savings may be hidden in other areas of your home. You may improve the energy-efficiency by improving insulation, sealing air leaks, and repairing ductwork.

Which HSPF is Right for Me?


In some locations across the country, a heat pump runs nearly year-round – cooling in the summer and heating in the winter. If you live in one of these areas, you may want to consider installing a high-efficiency ENERGY STAR® certified heat pump.* An ENERGY STAR certified heat pump may possibly save you more in energy costs if your current model isn’t listed as ENERGY STAR equipment.

Specific heat pump features often determine the efficiency rating of a heat pump. A high HSPF with these additional energy-efficient features may cost you more than a base or standard efficiency model, but it may save you money over the life of the system.

When determining if a high-efficiency heat pump fits your budget, you should evaluate how long you will use your new heat pump. By identifying how long you will live in your current home, you may be to determine how long it would take to recoup the initial costs of a high HSPF model heat pump.

  • Do you currently live in your “forever home”?
  • How long will your current home fit your lifestyle?
  • Would a job change require you to relocate?

If you determine that high-efficiency is right for your home but tough on your budget, HVAC financing can often help spread out the cost of a new heat pump or entire heating systems over a specific time frame. Why dip into savings you may have set aside for something else, add to an existing credit card balance or even consider a home equity line of credit? HVAC financing can be an effective means to fit high-efficiency equipment into your budget without breaking the bank.

Your licensed HVAC dealer can assist you in determining which heat pump and HSPF rating are right for your home and budget. 

*Proper installation and calculated equipment sizing are critical components to achieving optimal operational performance. Split system heat pumps must be matched with appropriate coil components to meet ENERGY STAR criteria.  Ask your contractor for details or visit www.energystar.gov.

Amana Heat Pumps

1 Heat Pump Systems. n.d. https://energy.gov/energysaver/heat-pump-systems.
2 Vanessa Stevens, Colin Craven, Robbin Garber-Slaght. Air Source Heat Pumps in Southeast Alaska. Fairbanks, Alaska: Cold Climate Housing Research Center, 2013. http://www.cchrc.org/sites/default/files/docs/ASHP_final_0.pdf.
3,4 U.S. Department of Energy. Air-Source Heat Pumps. n.d. https://energy.gov/energysaver/air-source-heat-pumps. 26 April 2017.
5 NC State. Heating Seasonal Performance Factor (HSPF)- Defined. n.d. https://energy.ces.ncsu.edu/heating-seasonal-performance-factor-hspf-defined/. 2 August 2017.
6 Paul W. Francisco, Larry Palmitter, David Baylon. Understanding Heating Seasonal Performance Factors for Heat Pumps. ACEEE, 2004. http://aceee.org/files/proceedings/2004/data/papers/SS04_Panel1_Paper08.pdf.