Air Source Heat Pump Running Costs: What to Expect in Sussex

An air source heat pump could cost from £650 to £870 a year to run. However, the size of your property, the capacity of your heat pump and its usage will all play a part in the final costs you pay. Additionally, the quality of your insulation, how efficiently your pump turns electricity into heat, and current UK energy costs will also be significant factors.

Compared to new boilers, heat pumps cost a similar amount to run, but for properties with older boilers, oil, LPG or direct electric heating, the running costs are significantly lower.

Air source heat pump running costs: Key factors at a glance:

Various factors influence the running costs of your air source heat pump. These include:

• The size and insulation of your home: A well-insulated home needs less heat to keep it warm, so the pump runs less often.
• The efficiency of the heat pump: Also known as the SCOP or Seasonal Coefficient of Performance. A higher SCOP means more heat per unit of electricity.
• Your electricity tariff: How much you pay per unit of electricity
• Your flow temperature and heating habits: Lower flow temperatures and steady, low-and-slow heating are cheaper than short, hotter bursts
• The system you are replacing: Savings are noticeable against new gas boilers, but significant against old, oil or LPG systems.

Throughout this guide, we’ll answer common questions about the running costs of an air source heat pump in the UK and compare it to other heating options, giving you a balanced assessment so you can make an informed decision.

How much does it cost to run an air source heat pump?

Based on the current energy price cap, an air source heat pump in a typical house could cost around £650-£870 per year to run. As mentioned earlier, these prices can vary significantly depending on how well the home is insulated, how efficient the unit is, your current electricity costs and more.

Heat pumps are popular because of their efficiency, and despite electricity costing much more per unit than gas, a good heat pump can deliver three to four units of heat for every unit of electricity it draws.

What will affect the running costs of a heat pump?

Five things affect your annual heat pump costs the most. For this guide, we have assumed a typical annual heating demand of around 10,000kWh. Your home’s actual figures depend on its size and insulation.

1. Heat demand: An average home in the UK can need approximately 10,000kWh, broadly in line with Ofgem’s typical household gas use of 9,500kWh per year. Smaller properties need much less; however, a larger property, or even a smaller one that is insufficiently insulated, may need much more.
2. Insulation and EPC rating: Loft and cavity wall insulation help reduce the heat your home loses, making the pump more efficient. A higher EPC band will normally mean lower running costs.
3. SCOP: The SCOP is how much heat you get per kWh of electricity. If your heat pump has a SCOP of 3.0, it means you get 3kWh of heat for every 1kWh of electricity used. Most modern units achieve around 3.0-4.0.
4. Unit price: The current cap has electricity priced at 26.11p per kWh; a specialist heat pump tariff could lower the rate on the electricity you use.
5. Flow temperature and habits: Heat pumps are at their most efficient when they run at lower flow temperatures over longer periods. Pushing flow temperatures up reduces your efficiency and increases your bill.

How do I work out the annual cost of running an air source heat pump?

To work out the annual cost of running an air source heat pump, take the approximate heat demand of your home and divide it by the SCOP of the heat pump. You then multiply this amount by the unit price. Our table below shows an example based on the current price cap of 26.11p per kWh in a house with a heat demand of 10,000kWh per year.

A properly installed air source heat pump that achieves a higher SCOP is almost certainly cheaper to run. For a more accurate cost for your home, simply use your home’s annual heat demand and your current electricity rate.

Air source heat pump running costs vs gas and oil boilers

Compared to a new gas boiler, an air source heat pump is comparable; however, when compared with older boilers or other fuels, a heat pump is considerably cheaper. Keeping with the 10,000kWh example from earlier and the July-September 2026 price cap for gas and electricity, we can see the difference in running costs.

These prices are, of course, only approximate and will vary per household. You should complete your own calculations for more figures closer to your usage.

Gas costs about a quarter of the price of electricity per unit. As a result, a heat pump needs a SCOP above 3.2 to start saving against a new efficient gas boiler. The majority of modern systems range between 3.0 and 4.0.

You can also switch off your gas entirely. This will remove the standing charge, which is around 29p per day or £106 per year.

The savings are largest against old boilers, oil, LPG and direct electric heating, with the Energy Saving Trust stating that hundreds of pounds per year can be saved switching from these old heating systems to more modern heat pumps.

How much does an air source heat pump cost to install?

Aside from running costs, there is, of course, the initial outlay on the heat pump installation itself. These can range substantially, with anything from around £4,000 to £15,000 being spent before any grants from the Boiler Upgrade Scheme. It’s worth noting that these prices are only a guide, and for some properties, heat pump costs can be much higher.

The current scheme allows for up to £7,500 towards heat pump costs per eligible household in England and Wales. We’ve explored how these grants work and the eligibility criteria in a recent blog. (link for other blog)

How much are the maintenance and servicing costs of an air source heat pump?

Air source heat pumps need annual servicing. This will help it run efficiently and maintain the warranty. With professional servicing, you can expect costs of £150-£300, but this could vary, especially if you have not looked after your heat pump and allowed its overall condition to deteriorate.

In between services, you can do a few things to keep running costs down and ensure servicing doesn’t involve any surprise fees.

• Keep the outdoor unit free of leaves, debris and obstructions
• Clean and check filters as per the user manual
• Watch for drops in performance and report them as soon as possible. Leaving issues, even small ones, could see your bills rise.

Can you reduce the running costs of an air source heat pump?

You can. A few simple steps, as outlined below, can make a difference.

• Switch to a heat pump or time-of-use tariff: Specialist tariffs exist that offer cheaper rates on the electricity your pump uses, making a noticeable difference to your annual costs.
• Run a lower flow temperature: Letting the pump run at a lower flow temperature is much more efficient than short, high-temperature bursts.
• Improve insulation in the property: Adding or upgrading your loft, cavity wall and floor insulation cuts heat demand, meaning the pump works less.
• Use the correct pump for your home: A well-sized system and correctly sized radiators or underfloor heating let the pump achieve a higher SCOP in everyday use.
• Pair with solar power or a battery: If you generate or store your own electricity, you can offset some of the pump’s consumption.

Considering a heat pump to help reduce your energy costs?

The running costs of a heat pump depend heavily on usage, system, maintenance and installation. Sussex Air Conditioning and Heat Pumps designs and installs air source heat pumps for homes and businesses across Sussex and the surrounding counties. Our systems can deliver 3kW to 5kW of heat for every 1kW of electricity used. As MCS-accredited installers, the systems we fit are eligible for government grants, helping reduce your installation costs. You can get a free quote for your installation today, or give us a call on 01273 434586 for further advice and information.

Air source heat pump running Cost FAQs

How much does it cost to run an air source heat pump per year?

A typical Sussex home could cost around £650 to £870 to run an air source heat pump, based on an assumed annual heating demand of 10,000kWh, a SCOP of 3.0-4.0 and the current electricity price cap of 26.11p per kWh.

Is an air source heat pump cheaper to run than a gas boiler?

At the current price cap, it is broadly comparable to a new efficient gas boiler but much cheaper than an old one. Because electricity is much more expensive than gas per unit, your heat pump should have a SCOP of above 3.2 to start saving against a new boiler. Most modern units are around 3.0-4.0.

How do I calculate my heat pump running costs?

Divide your home’s annual heat demand (in kWh) by the heat pump’s SCOP to find the electricity it will use, then multiply it by your electricity rate. For example, 10,000kWh/3.5= 2,857kWh x 26.11p= £750 per year.