Rating Heat Pumps in the Real World

Heat pump energy rating labels inform consumer purchasing decisions and utility incentive programs, though rarely do they come with the caveat mileage may vary. But when measuring the correlation between energy label ratings and actual performance after installation, the truth is that mileage varies a lot.

In fact, actual energy savings from residential HVAC systems is 30-50% lower than the federal test rating implies based on Northwest Power and Conservation Council’s Regional Technical Forum UES values. There are several reasons for this, but a big one is the ratings used to model savings do not accurately reflect energy savings in real-world conditions.

A group of utilities, government agencies, and Purdue University seeks to address this misalignment through the Heat Pump Rating Representativeness Project. The project will compare current test procedures with a new load-based test procedure and rating for heat pumps. The new procedure and rating measures equipment performance in real-world scenarios and under the native controls of the heat pump. This test procedure is especially valuable for variable speed ductless and ducted heat pumps with sophisticated controls and wider operating ranges. The research will inform the testing procedures necessary to create energy ratings that are accurate, easy to measure, and hard to game.

“Accurate performance metrics are an essential first step to transforming a market,” notes Christopher Dymond, senior product manager at the Northwest Energy Efficiency Alliance (NEEA). “When ratings do not match performance, consumers spend more money and utilities can’t predict loads on the grid.”

The project is backed by a collaboration of eight funding partners including: NEEA; Xcel Energy; Southern California Edison; Commonwealth Edison Company; Air-Conditioning, Heating & Refrigeration Institute; British Columbia Hydro; New York State Energy Research & Development Association; New England Energy Efficiency Partnerships. Field and lab testing beginning in early 2022 and is expected to be completed by Q2 of 2023. For more information, contact Christopher Dymond.