It doesn't make sense, though. You need the same amount of energy to heat up a room, regardless of how you produce the aforementioned heat. If the energy immedi

It doesn't make sense, though. You need the same amount of energy to heat up a room, regardless of how you produce the aforementioned heat. If the energy immediately dissipates, it means the building has very poor insulation. In order to heat up a radiator you need very hot water (>60C), that takes a while to heat up and then sits in the radiator slowly cooling off. Simply keep the air pump on for longer at 20C and you'll get the same temperature for _way_ less energy consumption. With a radiator you simply consume more energy upfront, you don't save money (on the contrary, you spend way more if the electricity doesn't come from fossil fuels because burning things is not efficient by any metric).