Solar hot water systems are very different to photovoltaic systems which generate electrical power (which can be used to power your home or 'paid' back into the national grid.
With domestic hot water solar panels, the panels absorb the suns energy (hence the importance of sighting them on a roof surface that gets the most direct sunlight), heating the water in the panels directly. A pump takes the water from the panels and in a direct system takes that hot water straight to your taps. This introduces problems with limescale and freezing in the winter.
A preferred installation would be an indirect system where hot water is pumped from the solar panels though a coil of a twin coil hot water cylinder in your home. This 'coil' heats up the cylinders water which you draw from as normal, before passing the solar panel system water back to the panels themselves to be re-heated.
The benefit is this is a closed system so you can add antifreeze to the water to prevent freezing and get all year round use. Limescale is also no longer a problem with a closed system.
With a twin coil cylinder fitted, the cold water in the tank can be warmed with the solar panel system coil passing through it which means your normal heating method - gas boiler etc doesn't have to run as long, saving you fuel even in winter.
For the solar panels themselves, there are two main types of collectors (solar panels) - a flat-plate and evacuated tube. Flat-plate collectors heat the water directly whereas evacuated tubes contain a fluid which evaporates at low temperatures. The resulting gas rises and condenses on a manifold, transferring its heat as it does so.
Now you know how they work, why not consider shaving your energy bill and saving the planet at the same time by having your own solar hot water system installed? For an instant idea on cost, visit
Solar Panel Quoter, enter a few details about your property and get an instant online installation price guide in minutes, without being hounded by salesman.
photo credit: brook
