energy efficiency ratio

American  

noun

1. a measure of the efficiency of a heating or cooling system, as a heat pump or air conditioner, equal to the ratio of the output in B.T.U./hour to the input in watts: EER

   A high-efficiency home window air conditioner has an energy efficiency ratio of 7.5 or more.

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Example Sentences

The cooling efficiency of a unit is measured by something called a seasonal energy efficiency ratio, which divides the cooling power produced by the energy consumed. 

From Forbes

The Seer rating, the Seasonal Energy Efficiency Ratio, was too low — even though the new system would be at least a third more efficient than my leaky clunker.

From New York Times