- You’ll need a large solar panel system to power a heat pump
- You won’t be able to power your heat pump with solar panels at night
- A 5.25 kilowatt solar panel system can power the average heat pump
Heat pumps offer an environmentally friendly alternative to traditional fossil fuel boilers, utilizing the ambient warmth from the air, ground, or water and relying on electricity for operation.
Given that electricity from the grid may not always originate from renewable sources, you might be contemplating the possibility of powering your heat pump with solar panels.
We have conducted an investigation into the feasibility of this approach, including an assessment of the associated costs, the potential requirement for a storage battery, and the projected timeframe for achieving cost parity in a system incorporating both a heat pump and solar panels.
Can you use solar panels to power a heat pump?
Certainly, it is possible to integrate your air source or ground source heat pump with solar panels to enhance the eco-friendliness of your heating and hot water system.
However, to utilize solar energy for powering your heat pump during the night, it would be necessary to have a storage battery. Without a storage battery, reliance on electricity from the grid would be inevitable for heating your home after dark.
Can you fully power a heat pump with solar panels?
You have the option to utilize solar panels to power your heat pump, provided that the system is sufficiently large to meet your electricity requirements.
Nevertheless, fully powering a heat pump with solar panels can be challenging since you also need to cater to the energy needs of the rest of your home.
For instance, if a 4 kW solar panel system is suitable for your property without a heat pump, you would require a system of more than double this capacity to fulfill the energy demands of a heat pump.
Moreover, winter presents additional challenges as the reduced sunlight may not be adequate to supply the necessary power for your heat pump. Consequently, you may only be able to partially supplement the energy supply to your heat pump during the colder months.
As long as you remain connected to the grid, there is no need to be concerned about your heat pump running out of power. However, you may still be susceptible to high electricity prices.
One alternative to consider is a solar thermal system, which harnesses sunlight to heat your water instead of generating electricity. This can help alleviate the water-heating load on your heat pump, reducing the amount of power required.
By lessening the load on your heat pump, you can potentially reduce the size of the solar panel system needed.
How many solar panels do you need to power an air source heat pump?
| House size | Heat pump size | Electricity required | Number of solar panels |
|---|---|---|---|
| 3 bedrooms | 5 kW | 25 kWh | 20 |
| 4 bedrooms | 10 kW | 60 kWh | 40 |
| 5+ bedrooms | 16 kW | 80 kWh | 62 |
The table provided illustrates various sizes of heat pumps and the corresponding number of solar panels required, based on the size of your residence.
Determining the necessary quantity of solar panels involves calculating the amount of energy essential for your heat pump to effectively heat your home.
In a typical UK household heated by a gas boiler, approximately 12,000 kilowatt hours (kWh) of gas are consumed annually. However, heat pumps exhibit significantly higher efficiency.
While a typical gas boiler operates at an efficiency rating of 95%, heat pumps generally achieve around 300% efficiency.
Consequently, heating your home with a heat pump would necessitate roughly 4,000 kWh, a requirement that can be fulfilled by a 5.25 kW solar panel system. Nonetheless, you would still need to rely on the grid to power the remaining electricity usage in your home.
Should you aspire to power both your residence and heat pump with solar energy, a larger solar panel system would be essential. It is important to verify that you have adequate roof space—approximately two square metres per panel—to accommodate the necessary system.
How much does an air source heat pump with solar panels cost?
| Size of heat pump | Cost of heat pump | Cost of solar panels | Total cost | Total cost with BUS |
|---|---|---|---|---|
| 5 kW | £10,000 | £14,935 | £24,935 | £17,435 |
| 10 kW | £13,000 | £29,870 | 39,870 | £32,370 |
| 16 kW | £15,000 | £47,949 | £62,949 | £55,449 |
The average cost of air source heat pumps is £10,000, but this amount decreases to £2,500 with the government’s Boiler Upgrade Scheme. However, it is important to note that this scheme is only intended to cover 60,000 homes within its initial three years, so it is advisable to promptly verify your eligibility.
For a 4.2 kW solar panel system, the cost amounts to £9,433, resulting in a total expense of £11,933 after factoring in the Boiler Upgrade Scheme discount.
This total may not be sufficient to power both your heat pump and your household, necessitating the installation of either a larger solar panel system or a storage battery.
Typically, a storage battery carries a price tag of around £4,500 and necessitates replacement after approximately 12.5 years. In comparison, a heat pump boasts a lifespan of 20 years, while solar panels typically endure for at least 25 years.
Consequently, the overall expenditure on solar batteries is estimated to be around £9,000, on average.
Do you also need a storage battery to power an air source heat pump?
You may operate an air source heat pump without a storage battery, but having one can be advantageous.
By possessing a storage battery, you have the capability to store a portion or all of the energy produced by your solar panels throughout the day.
This stored energy can subsequently be utilized during the night to operate your heat pump once your solar panel system has ceased generating electricity for the day.
Is your home suitable for a heat pump and solar panels?
In the majority of cases, your residence will be appropriate for the installation of a heat pump and solar panels, as neither usually necessitate planning permission.
However, if your property lacks accessible roof space, the installation of a solar panel system may not be feasible. Furthermore, if your residence is designated as a listed building or situated within an Area of Outstanding Natural Beauty, it may be necessary to request planning permission.
Insufficient roof space is also a crucial consideration, particularly in light of the substantial energy requirements of heat pumps.
Summary
Combining your heat pump with solar panels is a highly sensible choice from an environmental perspective, provided it is within your budget.
This approach allows for a reduction in emissions, enables the majority of your home’s heating requirements to be powered by solar energy, and eliminates the need to replace your heat pump and solar panel system for 20 years or more.
If you meet the criteria for the Boiler Upgrade Scheme, investing in a heat pump and solar panel system also makes complete financial sense.