If you have a new account but are having problems posting or verifying your account, please email us on [email protected] for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact [email protected]

Solar Panels with underfloor heating

  • 15-10-2021 6:51pm
    Registered Users Posts: 1,494 ✭✭✭

    This may be a stupid question, and apologies if it is.

    We have oil heating. Rads upstairs and underfloor heating downstairs. The underfloor heating is relatively old system, about 15 years old

    Is there anyway that solar panels can be used to heat the underfloor heating during the days?


  • Registered Users Posts: 849 ✭✭✭case_sensitive

    I'm guessing you found an answer somewhere.

    Your solar PV system will make DC electricity, which your inverter will make into AC for use in the house. It'd be unusual and not very efficient way to do it, but you could use that energy to heat water and pump around a wet underfloor system. It'd be incredibly inefficient though.

    Most people would have an air to water heating system in between; solar makes electricity, electricity makes warm water through the heat pump, warm water heats the floors.

    A dry underfloor system, that uses electric heating wire, could be powered from the solar, but without batteries, does it at the wrong time.

    Even in summer, my PV system isn't making good power before 9:30am, not enough to heat the house up before you go about your day. And in December/January, my 19 panels have made as little as 2kWh total for the whole day. Barely enough to keep a kettle of water boiled.

    You'll make plenty of power in July and August when you don't need it.

    Solar water tubes are used to heat water for washing etc, I've never heard of anyone having an array of them big enough to heat the whole house, but it's possible.