Yes, they simply move energy from one place to another. A fridge works on the same principle. For example, a bottle of white wine brought home straight from your local supermarket is at room temperature. If you put it in your fridge and wait a few hours it will be cold enough to drink. If you touch the back of your fridge during that time you will feel heat. The fridge has taken the low temperature energy out of the wine, compressed it up to a higher temperature and in effect has warmed the kitchen up slightly. By using the same process both Air Source and Ground Source Heat Pumps remove energy from a source and transfer it into your building. The sun naturally replenishes the energy removed from the air and ground.