Compares a year of heating on the current fuel with the same heat from a heat pump.
Most of the form is filled in already with figures that give a sensible answer. Adjust what you know and press the button.
Compare what a household spends heating on its current fuel with what the same heat would cost from a heat pump.
The heat demand is worked out from the household's own metered fuel use, not from a model, because a year of bills describes a particular house far better than any estimate of it. Supply the annual fuel use in the fuel's own unit (kWh for gas and electricity, litres for oil and LPG, kilograms for coal), its price per unit in pounds, and the seasonal efficiency of the existing appliance, which defaults to a realistic figure for that fuel instead of the one on the badge.
The comparison turns on one ratio. A heat pump costs less to run whenever its seasonal coefficient of performance beats the ratio between the price of a unit of electricity and the price of a unit of heat from the current fuel. The result reports that break-even figure explicitly.
SCOP must be the figure at the flow temperature the system is actually designed for. The same machine can return 4.2 at 35 degrees and 3.1 at 55, and quoting the first for a system designed at the second is the commonest way of overstating a saving.
This is a running cost comparison. It says nothing about the capital cost or any grant.
The same calculation answers on
POST /api/calculators/heat-pump-running-cost
and as the MCP tool heat_pump_running_cost.
How to call them.
No standard, grant or network rule requires one, and a heat pump will run without it. What a smart meter changes is which electricity tariff you can be on, and on a heat pump the tariff decides a large part of the running cost.
A heat pump is set up once, on commissioning day, for a house the installer had known for a few hours. The settings that decide the running cost can be improved through the first winter and checked every year after. This covers the settings worth revisiting and the checks worth making each year.
The grant that pays part of the cost of replacing a boiler with a heat pump in England and Wales. What it is worth, who can have it, and what the April 2026 rule changes opened up.
Short answers on whether a heat pump suits your house, what it costs to run, how loud it is and what has to change before one goes in.
It is meant to. A heat pump that ticks over all day costs less than one switched on and off, and the radiators are supposed to feel lukewarm. Here is why, and what that means for how you use it.
A heat pump quoted at 4.5 and one quoted at 3.1 may be the same machine measured differently. What each figure means, and which of them to compare quotations on.
A heat pump moves heat instead of making it, which is why it can deliver more heat than the electricity it consumes. What that means for your radiators and for the way the house is heated.