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- If a CCGT generates electrical power at 64% efficiency, and a heat pump generates 4 times the thermal power to electrical power, is that more heat energy out than the fuel has?
Something that has been on my mind a while.
If a CCGT generates electrical power at 64% efficiency, and a COP4 heat pump, powered by that generator, generates 4 times the thermal power to electrical power, wouldn't that mean we can get 256% heat out of the fuel's calorific value?
Maybe that is OK, but seems non-intuitive.
Where does the extra heat come from, or what am I not understanding?
I presume the answer is that because we're going from 'very hot' heat to colder heat, we can suck up some of the environmental heat? If so, is there not a more direct way to use the combustion temperature from a burning fuel to directly suck in extra heat from the environment, missing out the electrical generation bit?
If a CCGT generates electrical power at 64% efficiency, and a COP4 heat pump, powered by that generator, generates 4 times the thermal power to electrical power, wouldn't that mean we can get 256% heat out of the fuel's calorific value?
Maybe that is OK, but seems non-intuitive.
Where does the extra heat come from, or what am I not understanding?
I presume the answer is that because we're going from 'very hot' heat to colder heat, we can suck up some of the environmental heat? If so, is there not a more direct way to use the combustion temperature from a burning fuel to directly suck in extra heat from the environment, missing out the electrical generation bit?