In a nutshell, the panels on your roof collect energy from the sun and convert it into heat. A pump transfers this heat through some solar pipework to your hot water tank. This raises the temperature of your water (meaning you don't need to use your boiler as much) and you can then use this free hot water for your taps and appliances.

The diagram (left) shows how it works. At the top the sunlight hits the solar thermal panels. This increases the temperature of the panel and this heat transfers to a 'solar fluid' that circulates around the system. This hot solar fluid is then pumped through the pipes to the hot water cylinder.

Solar water heating systems require a special kind of hot water cylinder. These have an additional 'solar coil' in the bottom half and when the fluid circulates round this coil this transfers the heat to the water.

Unless you already have a cylinder with a solar coil then we will have to replace your existing tank with a solar ready cylinder. These come in different shapes and sizes, to fit the space available, but ideally are tall and thin.

Unlike conventional heating, which can heat water instantly at the press of a button, solar energy often will come through in bursts throughout the day. So that you can use this heat when you need it, solar water heating systems always require a hot water cylinder to store the heat.

To make sure that you always have hot water we also always recommend a secondary heating source. This means in most cases that you keep your existing boiler and connect it to the solar cylinder. The cylinders have two coils, one at the bottom for the solar and another in the middle for your boiler. Alternatively it is quite possible to connect-up the cylinder to back boilers on wood burning circuits or indeed to other heating sources. All our cylinders also include a 3kW immersion heater as standard (in the top), powered by mains electricity, as an additional, optional form of heating.

We can integrate a solar system into most types of water heating systems: solar works well with both the conventional setup (a vented cylinder and a header tank in the loft) and also with mains pressure systems. Solar can be made to work with a combi-boiler, but this is slightly more complicated and more costly – please see our FAQs.

Sensors in the panel and in the water cylinder continuously monitor their temperatures. An electronic controller displays these temperatures, so you can always see what is happening and how much heat the system is providing. It also tells you the temperature at the top of the tank – which is the temperature the water will come out of the taps.