Heat Pump vs Gas Cost Calculator

Compare annual heating and hot water costs with a heat pump or gas, including delivered-kWh cost, savings, payback and cumulative difference over 5, 10 and 15 years.

Compare real heating and hot water costs

Heat Pump vs Gas Cost Calculator

Enter your annual demand or estimate it from floor area, insulation, climate and occupancy to compare heat pump versus gas with a clear, mobile-friendly decision layout.

Calculation mode

Known annual demand

Heat pump

Gas

Advanced block

Subsidies, financing and future price changes are not included.

Complete the comparison to see results

The comparison will show annual and monthly cost, payback and cumulative difference over 5, 10 and 15 years.

Brief introduction

This comparison tool is designed for households that want to know whether a heat pump can reduce annual cost versus gas without getting into subsidies, financing or specific brands. The calculation focuses on delivered energy, maintenance, fixed gas cost and any extra upfront cost.

How the comparison works

You can work in two modes. In the first one you enter a known useful annual demand. In the second one you estimate that demand from floor area, insulation level, climate severity and whether hot water is also included.

Once useful demand is defined, the calculator converts that energy into annual electricity use according to the heat pump SCOP and into annual gas use according to the boiler seasonal efficiency. It then adds maintenance and, for gas, the annual fixed charge.

What most affects heat pump vs gas cost

The biggest driver is usually the combination of useful annual demand, heat pump SCOP and the unit price of each energy source. A home with high demand amplifies both savings and estimation errors.

The annual fixed gas cost also matters. Even when the gas variable price looks competitive, a high standing charge can worsen the outcome when annual demand is not very large.

Useful demand, SCOP and efficiency

Useful annual demand represents the heat actually delivered to the home. That is why it is the right basis for comparing different technologies.

SCOP shows how many delivered kWh the heat pump provides for each kWh of electricity consumed. For gas, seasonal efficiency plays the equivalent role by showing how much useful heat is obtained from the fuel.

How to interpret the break-even point

If the heat pump saves money every year and also has an extra upfront cost, the break-even point estimates how many years are needed to recover that initial difference.

If annual savings are zero or negative, no numeric payback is shown because the extra cost is not recovered under the current assumptions.

Frequently asked questions

What exactly does this calculator compare?

It compares the annual heating and hot water cost of a heat pump versus gas using the same useful annual demand and adding maintenance, fixed gas cost and any extra upfront cost.

When should I use the estimated mode?

Use it when you do not have a reliable figure for useful annual demand and only know floor area, insulation quality, climate and number of occupants.

Why might the heat pump not pay back?

Because a low SCOP, high electricity price, low annual demand or high extra upfront cost can make annual savings too small to recover the additional investment.

Does cumulative difference include the extra upfront cost?

Yes. The 5, 10 and 15 year horizons add the extra upfront cost to the heat pump scenario so it can be compared directly against gas.