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Is it right that I refer to an Air Source Heat Pump as an energy generator?

At events I've spoken recently at I've started to refer to heat pumps as an energy generator so want to explain why.

If it feels wrong to call it a generator it’s because we use them to heat our homes and hot water and it’s consuming electricity so surely it’s not a generator of energy.

Solar panels and wind turbines generate energy - these are easier to comprehend because we see and feel sunlight and wind and can understand how energy comes from those sources and some clever technology converts that to electricity that we can consume any way we want to as well as reducing our purchase of electricity from the grid.

However electricity generation is really the conversion of energy from one form (oil, gas, sunlight, wind) into another, electricity, as you can’t create energy out of thin air; PV panels, wind turbines and burning stuff is just the clever technology of converting a form of energy into electricity. Electricity is a very versatile form of energy - heating, lighting, driving, cooking, powering all our gadgets, etc. The output of a heat pump though is heat which we use pretty much only for heating and hot water so it’s much less versatile which probably contributes to the impression it's not generated but it has still generated that output - so hence it’s a form of energy generation. But that isn’t the whole of my definition. A heat pump is using electricity (think of that as its fuel) to extract heat from the air and if you compared its output to that of an electric heater you find the heat pump produces 3 to 5 times the output because of the magic of extracting heat from the air. In fact the fuel, if you like, is both the electricity and the air around us.

And this is what I mean when I say a heat pump is a generator; not the conversion of electricity to heat but that for each kWh of electricity consumed it generates 3 to 5 times as much energy output. For the home that means consuming 1/3rd to 1/5th electricity if the heating and hot water were purely electric. If gas and electricity were to cost the same per kWh then you can instantly see how much better it is - let alone the environmental benefit of not burning stuff.

In fact I’d go so far as saying it really is generating energy out of thin air.


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