Solar Water Heating for a Family

Mehdi and his family have installed an evacuated tube solar water heating system on the roof of their house. It produces around half the hot water they need over the course of a year.

Tapping the sun

Mehdi and his partner decided to install a solar water heating system on the roof of their three storey house in Wales to reduce both their energy bills and their carbon footprint. Their system provides around half the hot water they need over the course of a year, is fully automated and integrated with their existing gas boiler so that they always have enough hot water, whatever the season or the weather.

On their slate roof, Mehdi and his family installed an evacuated tube solar water heating collector with 30 evacuated glass tubes. Evacuated tube collectors can reach higher water temperatures than traditional flat plate solar collectors and work more efficiently on days when it is sunny but cold. However, they are more visible than flat plate collectors and can often be a bit more expensive.

The collector is connected to a twin coil hot water cylinder with two heating coils – one connected to the solar panel, another to the gas boiler. In Mehdi’s house, the cylinder and the pump that connects it to the solar collector is hidden away in a cupboard in the bathroom. The controller, which measures the temperature in the collector and in the cylinder and switches on the solar water heating pump when necessary, is mounted in the kitchen as Mehdi likes to check how much hot water the system produces.