• Solar panels – there are typically fitted to the roof of the building and contain collectors. These collectors absorb and retain the heat from the sun’s rays and transfer this heat to a fluid.
• Hot water cylinder – this stores the hot water that is heated during the day, making it available for later use.
• Plumbing system – this is a simple pipe system which enables the heated fluid to flow from the panels to the coil in the hot water cylinder. Sometimes a pump is used to help move the heated fluid around the system.

They are usually mounted on your roof. A solar thermal system can provide around a third of your annual hot water and, if combined with a well-designed thermal store (hot water tank) and heating system, can provide some winter space heating. Once installed, solar thermal panels provide heat for free with no fuel input other than a small amount of electricity used for pumping the water, hence they are a near-zero carbon fuel source (note: a few solar systems use solar photovoltaic (PV) panels for pumping to eliminate the electricity use completely.)