Heat pumps: smarter, cleaner, cosier home heating

Heat pumps vs Gas boilers

Cost to run: Cosy heat pump customers on the Cosy Octopus tariff saved an average of £219 last year compared to using a gas boiler running at 85% efficiency on our standard variable tariff.

This figure is based on the actual energy consumption of all Cosy heat pump customers on a Cosy Octopus tariff between 19 March 2025 and 18 March 2026, using tariff rates at the time.

We compared this to the cost of producing the same amount of heat with a typical UK gas boiler operating at 85% efficiency, priced using our Flexible Octopus (standard variable) tariff at the same time.

Savings from gas standing charges were included only for customers who had fully removed their gas supply (less than 3% of customers).

Actual savings vary depending on system design, tariff choice, home insulation and energy use.

Efficiency: A heat pump is around 4x more efficient than a gas boiler

Heat pumps don’t generate heat by burning fuel. Instead, they transfer existing heat into your home. This means they can deliver multiple units of heat for each unit of electricity used.

Based on performance data from a fleet of installed Octopus Cosy heat pumps, typical seasonal performance (SPF or SCOP) is around 3.6. This means around 3–4 kWh of heat is delivered for every 1 kWh of electricity used (an effective efficiency of 300–400%).

By comparison, typical UK domestic gas boilers operate at around 85% efficiency, delivering approximately 0.85 kWh of heat per 1 kWh of gas used.

On this basis, a heat pump can be around 4× more efficient than a typical gas boiler.

All our heat pumps are independently tested by the Building Research Establishment (BRE), with SCOP values published on the Microgeneration Certification Scheme (MCS) product database.

This comparison is based on typical real-world performance of Octopus Cosy heat pumps and typical UK domestic gas boilers. Actual efficiency will vary depending on the property, system design, and usage.

For more information, explore our Octopus Cosy heat pump fleet performance dashboard.

Lifespan: Heat pumps typically last longer than gas boilers

The expected lifespan of a typical gas boiler is 10–15 years. A heat pump typically has a lifespan of 15–20 years, with UK government research indicating an average of around 20 years. Manufacturer Daikin reports similar ranges. Actual lifespan depends on factors such as installation quality, maintenance, usage patterns, and operating conditions.

Emissions: Cut carbon emissions by around 80% with a heat pump

A typical medium-use home could reduce operational heating carbon emissions by around 85% using an electric powered Octopus Cosy heat pump compared to a typical UK domestic gas boiler, depending on factors like home efficiency, system design and usage, based on the following calculation:
Gas CO2 = (A*D) = 2.42 tonnes per year
Electricity CO2 = (A/B*C*E) = 0.37 tonnes per year
Carbon saving = 2.05 tonnes or 85%

Where A - E are:
A - 11,500 Ofgem gas consumption values for a typical medium-use home
B - 360% typical seasonal coefficient of performance from our fleet of Octopus Cosy heat pumps
C - 85% typical gas boiler efficiency from a BEIS study
D - Gas fuel emissions of 210 gCO2/kWh (SAP 10.2)
E - Electricity fuel emissions of 136 gCO2/kWh (SAP 10.2)

Based on these sources, heat pumps typically produce lower operational emissions when heating the home than gas boilers.

For more information, explore our Octopus Cosy heat pump fleet performance dashboard.

General heat pump claims

Heat pumps give reliable, consistent heating and hot water

The heat pump user survey report by Nesta from May 2023 summarises that "users are highly satisfied with their heat pumps". It states "People living in England, Scotland and Wales who own their home and use a heat pump to heat it are satisfied that heat pumps are safe, reliable, quiet heat sources that are effective for space heating and producing hot water". Find the full report here.

Heat pump heating makes the air healthier in your home

Homes with a heat pump emit far less harmful nitrous oxide (NOx) emissions from gas boilers and cookers, significantly reducing asthma and other respiratory illnesses. According to the Sustainable Markets Initiative Cleantech homes report.

A heat pump can add thousands to your property value

Analysis by the Department of Land Economy at the University of Cambridge suggests a 16% value uplift for new-build homes with enough solar and battery storage to eliminate energy bills. A further study of over five million existing properties indicates a 2-3% value increase for existing homes with solar panels or heat pumps (versus like-for-like gas-heated homes). According to the Sustainable Markets Initiative: Cleantech Homes report, 2024.

As of April 2025, the average house price in the UK is £265,497 according to Land Registry. Therefore, a 2-3% value increase for an average house priced at £265,497 would be between £5,310 and £7,965.