Solar heating using a hot water tank

	KEY: 1 Cold water supply 3 Boiler 2 Storage tank 4 Hot water taps Your current hot water system works something like this : Water (1) from a tank in the loft enters the hot water tank (2) and is heated by a separate water circuit from the boiler until it reaches a usable temperature, it is then stored until used at the taps (4). Now look at what needs to change when adding solar energy.