Solar PV or Solar Thermal?
Many of our heat pump clients in Cornwall, Devon, Somerset and beyond want to combine our installations with other forms of renewable energy, such as solar panels, in hopes of producing the most efficient and eco-friendly home they possibly can. However, many people aren’t sure which type of solar panel system is best to use alongside a ground or air source heat pump.
Firstly, it’s important to understand that although there are many types of solar panel systems available that can be floor mounted, roof mounted and made into tiles with many different functions. If we look specifically at combining heat pump and solar technology though, there are two options.
Solar thermal
Solar thermal technology involves a water heating system that uses heat from the sun to warm domestic water. Solar water heating uses either flat plates or evacuated tubes to collect energy from the sun which is stored in a hot water cylinder inside the property.
Solar thermal considerations
The first question to ask is if you have an adequately sunny place to locate your solar panels. This is because solar panels will only be able to produce hot water when they have gathered sufficient energy from the sunshine, and even then, they may need to be supplemented with another energy producing system. Investing in an additional system would take up more space and more of your budget.
Solar thermal compatibility with a heat pump
While it’s possible to use a heat pump and solar panels in conjunction, both technologies essentially do the same job, so you would be doubling your costs for little or no benefit. This is because an air or ground source heat pump will be able to produce 100% of your property’s hot water and heating demand. Some argue this point in the following way; “With a solar panel system also installed, the heat pump will not need to work as hard and consequently there will be a reduction of running costs.”
Unfortunately this isn’t the case, as in order to fulfill its job of producing 100% of your property’s heating and hot water demand, the heat pump must be sized correctly, so you won’t be able to “get away with installing a smaller system” and you might have to use the heat pump to supplement the energy production expected of the panels, when they do not perform sufficiently, due to a lack of energy gathered from the sun for example.
Solar PV
Also known as solar photovoltaics (PV), solar panel electricity systems collect energy from the sun through photovoltaic cells before converting that energy into electricity for your home using technology that even works on a cloudy day!
Solar PV compatibility with a heat pump
Solar PV systems are the perfect renewable partner for heat pumps. PV systems create electricity by using sunlight and heat pumps can use that electricity to create up to four time as much energy as they consume, before converting that energy into heating and hot water. Using relevant measures of energy, for every kW of electricity that your PV panels produce, your heat pump can create up to 4.3kW of heating and hot water.
If your heat pump is being run or supplemented by the electricity produced by your solar PV panels, your running costs would decrease even further. Any additional electricity can be used to power other parts of your home and you could still sell your electricity back to the national grid. Solar PV systems and heat pumps really are a match made in renewable heaven!
Solar PV considerations
The larger your solar PV system is, the more electricity it can generate. This subsequently increases the cost of the solar PV system, but also increases the amount of money it could save you.
What do we suggest?
If you have already decided that you would like a heat pump to produce 100% of your property’s heating and hot water demand, but want to use additional renewable technologies, Source Energy would suggest that investing in a solar PV system is your best option. Solar PV panels are able to produce the minimum amount of electricity that the heat pump requires in order to run, in addition to supplementing the electricity demand of your home. Also, by selling electricity back to the national grid you can benefit from the Feed In Tariff, by earning back the cost of the panels while producing free electricity to run your heat pump.
Please call 0800 865 4328 today if you have any questions about how heat pumps and solar panel systems could be suitable for your project. You can also visit our Solar PV Partner page for information about Cornwall Solar Panels.
Click the image to read about a state-of-the-art homes development in Cornwall which uses heat pump and solar technology. Source Energy installed Thermia/Danfoss ground source heat pumps with boreholes to provide hot water and underfloor heating for the properties.
