Save on Energy Bills
Find out how you can save up to 50% on energy bills

How Can I  Save Money On My Energy Bills?

Alongside improving your energy efficiency and helping reduce carbon emissions when you install a heat pump, you can also make substantial savings on your energy bills, especially if you are replacing a G-rated oil or LPG boiler. You will still have to pay some fuel bills because a heat pump is powered by electricity, but you will save on the fuel you are replacing. This means you are more likely to see lower running costs with a new heat pump. 

For example, based on the Mitsubishi Ecodan 8.5kW Air Source Heat Pump unit providing 100% of your heat and hot water demands, you could save over 50% on energy bills:

  • Based on the system having a Seasonal Coefficient of Performance (SCoP) of 3.44 at 55′C flow temperature (see below section for description). 
  • The average price for electricity per kW hour is 12.74p. Due to SCoP figure above, you should achieve 3.70p per kWh (heat energy) on average over the year.

  •  Oil has a calorific value of 10.31 meaning you get 10.31 kWh’s of heating per litre consumed. The average dwelling runs 1,500-2,000 running hours per year.

  • According to Which?, the average cost of oil heating for a three-bedroom house is around £1,355. This compares to between £770 and £950 for mains gas, depending on the efficiency of your boiler:
  • A new A rated oil boiler is generally 90-93% efficient
  • An old G rated oil boiler is generally 70% efficient, therefore;

  • With 100% boiler efficiency, you could achieve 5.33p per kWh (heat energy)– 30% saving with an Air Source Heat Pump  based on an oil running cost of 55p per litre.
  • 93% boiler efficiency can achieve 5.74p per kWh (heat energy) – 35% saving 
  • 70% boiler efficiency can achieve = 7.62p per kWh (heat energy) 51% saving 

If you currently have an LPG boiler or are looking to install a Ground Source Heat Pump or larger Air Source Heat Pump, you could see an even greater saving. 

What is SCoP?

The efficiency of a heat pump is referred to as the Seasonal Coefficient of Performance or SCoP. This is the ratio between heat delivered and power consumed which will vary throughout the year depending on the outside temperature. The average UK winter heating temperature has an average SCoP of 3.4:1, providing 3.4 units of heat for each unit of energy consumed, resulting in significant energy savings.

What is a kilowatt hour (kWh)?

A kilowatt hour (kWh) is a measure of energy that equates to 1,000 watts – or 1 kilowatt (kW) of energy being used for one hour. The performance of every electrical household appliance is measured in watts (UK Power).

Please note that these figures are an estimate only. Savings will depend on each specific installation and are not guaranteed.

Heat pumps can provide up to 100% of your heating and hot water needs. Read one of our case studies here to find out how Mrs Stacey’s home achieved 100% of its heating and hot water needs and helped save on energy bills.

8.5kW Mitsubishi Ecodan SCoP details (

The electricity figure is based on the average electricity cost tariffs highlighted in the UK electricity suppliers chart. Costs correct as of October 2018 (