Report Released: Cold Climate Air Source Heat Pump

Apr 24, 2018

CEE has released a final report for its Cold Climate Air Source Heat Pump research project, funded by CARD. Air source heat pumps (ASHPs) support more efficient space heating and lower energy costs in homes located in states with cold climates, where natural gas may be unavailable. Although ASHP technology has been available for many years, there has been concern over its effectiveness in climates with temperatures as cold as Minnesota’s.

ASHPsmall.JPGThis project installed ASHPs in six Minnesota homes where natural gas was unavailable. Propane furnaces were used for back-up at four sites and the existing electric resistance baseboards were used for back-up in two homes. Staff alternated between the furnace or electric resistance baseline and ASHP operation throughout the heating season, and the equipment was monitored to characterize the energy use and determine if the system could effectively meet the space heating load. Occupant comfort and acceptance was evaluated from monitored space temperatures and occupant surveys.

Main research conclusions

  1. Inverter driven cold climate ASHPs are capable of operating at very cold temperatures. The monitored performance of the heat pumps systems verify that their installed performance is in line with the manufacturer performance specifications.

  2. When heat pump equipment is installed and operated with an appropriate back-up system they provide a cost effective and energy efficient space conditioning option for homes without access to natural gas.

Research staff monitored field performance tests to help confirm the operation of newer generation ASHP technologies to support their use in Minnesota's utility Conservation Improvement Program (CIP). The results from the study helped determine ASHP savings potential and facilitated the design of CIP.

Access the full report: Cold Climate Air Source Heat Pumps