Heat pump or standard electric cylinder?
What each one costs to buy, what each costs to run, and who should pick which.
Last reviewed 2026-09-02
This is the main decision when a cylinder is being replaced, and the honest answer is that it depends on how long you are staying in the house.
Standard electric
An element heats the water directly. Cheapest to buy, simplest to replace, goes wherever the old one was. It uses the most power of any option.
Heat pump
Moves heat from the outside air into the water instead of generating it. Uses roughly a third of the power. Costs more up front, and it has to go outside — which frees up the cupboard the old cylinder was in.
How to choose
- Staying long term — heat pump. The running cost saving adds up and it is the cheaper option over the life of the unit.
- Rental or selling soon — standard electric. Lowest up front cost, and the power bill is not yours.
- No outdoor space — standard electric. A monoblock heat pump cannot go in a cupboard.
One thing people miss
A heat pump cylinder needs about a metre of clearance above it so the anode can be pulled and checked, which the manufacturer requires every five years. If it gets wedged into a tight alcove it cannot be serviced. Worth thinking about before the install, not after.