Common joke says that heaters are 100% effient because all they make is heat. How much energy is actually lost?

Question

Common joke says that heaters are 100% effient because all they make is heat. How much energy is actually lost?

In: Physics

Answer 1

Typical heaters are in fact 100% efficient. But you can do better by being willing to cool it down a bit more outside, by making a heater that is effectively the opposite of an air conditioner. Rather than *creating* heat, it just *transports* heat, and you can move heat for less than the cost of making it. These heat pumps can reach effective efficiencies of 200-300%.