We recently had our heater changed to a heat pump and whilst producing the same amount of heat, it’s also very energy efficient, using a good chunk less energy than our previous heater.
How do they work and how are they so damn efficient?
We recently had our heater changed to a heat pump and whilst producing the same amount of heat, it’s also very energy efficient, using a good chunk less energy than our previous heater.
How do they work and how are they so damn efficient?
Moving heat is cheaper than creating heat.
An air conditioner runs a motor to run a compressor which pushes a fluid through a set of pipes moving heat from a cold spot to a hot spot. A heat pump in heating mode does the same thing, except the cold spot is outdoors.
The amount of heat moved to the hot spot is equal to the amount of heat moved to the cold spot plus the work done (heat created).
Imagine a terrible, broken-down heat pump that just barely works. The amount of heat moved from the cold environment to the hot environment is near zero. The amount of heat moved from the hot environment to the cold one is near zero. The main source of heat in the whole system is the pump which just gets hot because it’s doing work pumping a fluid. An electrical heating system is basically just that. It’s a heat pump moving zero heat, instead of using a motor, it just uses a resistive electric wire. A motor doing zero useful work that just gets hot is essentially an electric heater. If you can get that motor to do any useful heat-pump work at all, of course it’s going to increase the efficiency of the system.
The only drawback of heat pumps is that you need all the fiddly bits to move heat from A to B. An electric heater is easy because it just heats up the area where it is located.