It’s a cold January morning. Your air source heat pump is warming the house, but the sun has barely risen and your solar panels aren’t producing much electricity. Does that mean these two technologies don’t work well together?
Not at all. Solar panels can help lower the cost of running an air source heat pump. How much they contribute depends on when your home generates and uses electricity.
At Electrical Innovations, we’re a family-run, MCS-certified solar installer serving homeowners across Derby and the Midlands. Here’s what you need to know if you’re thinking about bringing solar panels and a heat pump together.
How do solar panels work with an air source heat pump?
An air source heat pump uses electricity to draw heat from the outside air and bring it into your home. Because it moves existing heat rather than creating it, it uses less energy than many other electric heating systems.
Solar panels generate electricity. They don’t need to connect directly to the heat pump. The electricity they generate helps power anything running in your home, including the heat pump. If the panels don’t produce enough electricity, your home will automatically draw the rest from the grid.
Can solar panels fully power an air source heat pump?
They may cover its demand at times, but a typical domestic solar system won’t run it solely on solar electricity all year.
Timing is the main challenge. Solar panels produce most of their electricity during the longer days of spring and summer, while your heat pump uses most electricity in winter. Your panels could generate as much electricity over a year as the heat pump uses, but that generation won’t always coincide with your heating demand. As a result, you may export surplus power to the grid in summer and buy more electricity from the grid in winter.
So, you should ask your heat-pump installer for its expected annual electricity use, then compare that with a solar generation forecast. Don’t rely on the heat pump’s headline rating. An 8kW rating usually describes its heating capacity, not how much electricity it continuously uses. Your roof, shading and location matter, too, as our guide to how many solar panels you need explains.
Do I need a solar battery to run a heat pump?
No, but adding one may help you use more of the electricity your panels generate. A solar battery storage system saves surplus daytime electricity for use after sunset.
However, a battery saves electricity for a day, maybe two, if you have a large enough one. It can’t, of course, save a sunny day of electricity in June for a cold January morning. Work with a trusted solar installer to calculate whether a battery is worth it for your home and, if so, what capacity you need.
Capacity tells you how much electricity a battery holds, while its power rating tells you how much it can release at once. Read which solar battery should I choose? to learn more.
How can you make solar panels and a heat pump work better together?
If you’ve already got solar panels and a heat pump installed, or are thinking of taking the plunge, here are a few tips to help them run more efficiently together:
Plan for future electricity use. If you’re installing solar but don’t yet have a heat pump, mention your plans. Your installer will consider the extra demand when discussing panel numbers, inverter capacity, battery options and future expansion.
Heat water during daylight. Your heat-pump installer may be able to schedule some water heating for the middle of the day. The cylinder will then store that heat for later. Follow their advice so the system still meets your hot water needs.
Let the heat pump operate as designed. Heat pumps often work best when they maintain a steady temperature. Constantly switching yours on and off to follow the sun could reduce its efficiency and leave your home cold.
Consider your tariff and controls together. If you have a flexible tariff and solar battery, you may be able to use solar electricity during the day, charge the battery when grid electricity is cheaper and use the stored power when rates are higher.
Can you add a heat pump if you already have solar panels?
Adding a heat pump doesn’t mean replacing your solar system. It simply becomes another appliance using electricity in your home.
Your installers should, however, check that your electrical supply and consumer unit (electrical panel) can support the extra demand. More panels or a battery may help, but neither is an automatic requirement. If you want to increase generation, find out whether you can add more panels to your existing solar set-up.
Plan your solar system around your heat pump
Electrical Innovations designs and installs domestic solar panel systems, inverters and battery storage across Derby and the Midlands. If you have a heat pump or plan to install one, we can account for it in your solar design and explain how much electricity solar panels on your roof could generate.
Contact us to discuss a solar system designed around your home and energy use.
