It is a storage vessel for storing larger quantities of hot water. In Germany it is called a boiler, because you put all your heating sources into the thermal store, also known as a buffer. The boiler (buffer) allows you to take the hot water to any heating source you require. You can use it for hot water via a heat exchanger giving you hygienic fresh hot water but at a lower temperature, the same way as a combi boiler works but without the gas. It is one of the best systems for using with under floor heating but you would require a large volume, of about 800 litres. This is because you need to store the energy throughout the summer, ready to be used for the heating in the winter. If you was using a back-up heating source, i.e. ground or air source which uses a high demand of electricity, a thermal store would reduce your running costs of electricity of up to about 30%, plus the heating source would not have to work so hard.
Ample Energy would recommend that more properties use this technology with their solar system. The saving for this system could be up to 60%. Please contact us for further information.
The picture shows a 1000 litre thermal store; this customer had 3 x 35 litre per minute of fresh hot water modules, also run his underfloor heating for his home. The size of the solar system was 25sqm, which was well oversized for the thermal store, but during the summer we used his swimming pool as a heat dump. During the winter the solar collectors heated the thermal store sufficiently as we only needed to keep the thermal store at 47°C. The back heat used was a 40Kw direct heat gas boiler.