Solar Thermal Systems
Use free heat from the sun to warm your water for a lower carbon footprint.
Solar thermal systems fit solar panels, also known as collectors, to your roof. Heat transfer fluid (water and antifreeze) flowing through these panels is heated by the sun and pumped to a heat exchanger inside the water tank in your home. This exchanger then heats the water inside that tank. The heat transfer liquid flows back to the solar panels once the heat is released.
As solar panels only function in direct sunlight, it is important that the roof you place your solar panels on is east, west or south facing and isn’t in the shade for most of the day. Solar panels fitted to your roof can be used alongside a conventional boiler, collector or immersion heater to further warm water especially in the winter months. Once you have confirmed that a solar thermal system is the right energy saving solution for your home, you can choose between on roof or in roof solar thermal systems and evacuated tube collectors or flat plate collectors.
- The system works throughout the year
- Lower home carbon emissions
- One time cost (except if any repairs are necessary)
- Reduced energy bills
In Roof Solar Thermal Systems
If you are looking for a more aesthetically pleasing solar thermal system, then in-roof ones are the perfect option for you.
Rather than solar collectors being mounted directly onto the roof tiles, which is the case for on roof solar thermal systems, the solar panels are built into the roof and sit lower. A water barrier is also fitted prior to the solar panels itself to divert water behind the panel. With this type of system serving both as a generator of electricity and as the roof covering, and it being trickier to install, it can be more expensive.
Evacuated Tube Collectors
Evacuated tube collectors are the preferred choice in the UK as they perform better in cooler climates. This type of collector consists of a bank of glass tubes through which cool vapour liquifies and flows to the bottom of a copper heat pipe. There it gets heated by the sun after which it flows back up to the storage tank heat exchanger. The heat transfer liquid is only in the evacuated tube for a very limited time. This with its insulation of 3’ inch rock wool and a copper pipe ensures there is a minimal ambient heat loss making it more efficient.
Flat Plate Collectors
Flat plate collectors are the more traditional option. The cold water from the water tank enters a system of coated copper collector tubing. This is protected by a back plate on one side and insulation and a toughened glass front on the other. The fluid that is heated sits in the flat plate for a longer time which means that it is susceptible to greater heat loss. In colder climates, flat plate collectors can get covered in snow making them less effective, but they can be up to 15% cheaper than evacuated tubes. If your household does not utilise a lot of hot water then this may be your preferred solar thermal option.