64% n.th + COP4 = more heat out of fuel than its calorific value?

In summary, the conversation discusses the efficiency and COP (coefficient of performance) of a CCGT (combined cycle gas turbine) and a heat pump. The question is raised about whether it is possible to get more heat out of the fuel's calorific value by using a heat pump powered by the generator. One person expresses confusion about where the extra heat comes from and suggests a more direct way to use the heat from burning fuel. The other person explains that COP is not the same as efficiency and can go over 100% due to energy being moved, not created, and limitations on temperature differences. A link is provided for further information on heat pump efficiency.
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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?
 
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Short summary of @Llewelyn 's point: COP is like efficiency, but it is not efficiency. It is always way over 100%. That's not a violation of the laws of thermo. The energy isn't being created, just moved, and there are hard restrictions on the available temperature deltas.
 
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FAQ: 64% n.th + COP4 = more heat out of fuel than its calorific value?

What does the equation "64% n.th + COP4 = more heat out of fuel than its calorific value" mean?

The equation represents the efficiency of a fuel-burning system, where 64% of the energy released from the fuel is converted into usable heat, and the Coefficient of Performance (COP) is 4 times the fuel's calorific value.

How is the efficiency of a fuel-burning system determined?

The efficiency is determined by measuring the amount of heat produced by the fuel and comparing it to the fuel's calorific value. The higher the percentage of heat produced, the more efficient the system is.

What is the significance of having a COP of 4 in the equation?

A COP of 4 means that the fuel-burning system is able to produce 4 times the amount of heat compared to its calorific value. This indicates a highly efficient system that is able to extract more energy from the fuel.

How does this equation relate to renewable energy sources?

This equation is primarily used for traditional fuel sources, such as coal or natural gas. However, it can also be applied to renewable energy sources, such as biomass or solar power, to measure their efficiency in converting energy into usable heat.

Can this equation be used to compare different fuel types?

Yes, this equation can be used to compare the efficiency of different fuel types. By plugging in the respective values for each fuel, the equation can determine which fuel is more efficient in producing heat.

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