Oxford study proves heat pumps triumph over fossil fuels in the cold::Published Monday in the scientific journal Joule, the research found that heat pumps are two to three times more efficient than their oil and gas counterparts, specifically in temperatures ranging from 10 C to -20 C.
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Okay, I suppose you wouldn’t do that when replacing and old furnace but rather go for a hybrid system. In Europe loads of people are reacting to hiked gas prices and have perfectly fine furnaces in place that they don’t want to get rid of.
That’s a good case for mini-split systems.