Question

An air conditioner uses 10543 J of energy to run, but only 5818 J of energy is used to heat or cool the air of a home. What is its energy efficiency?

Answer 1

In order to calculate the efficiency, we need to divide the useful energy by the total energy used:

$e=\frac{P_{useful}}{P_{total}}$

So, using the given information, we have:

$e=\frac{5818}{10543}=0.5518=55.18\%$

Therefore the energy efficiency is 55.18%.