• What is ST? ST is the general international abbreviations for Solar Thermal Conversion. • What is Solar Thermal Conversion? If solar radiation /light falls onto a heavy copper plate, this energy is absorbed into it (as heat) and transferred to a pipe system linked to this so-called “absorber plate” with the absorber medium (e.g. water) in it. • What is a ST Collector? An ST Solar-collector is an assembly of a series of absorbers to a collector pipe (in) and collector pipe (out). The total package has been built into an aluminium frame, at the front provided with a glass plate (special glass) at the back and sides entirely isolated with thermal insulation material. • How does a Solar-collector work? In the closed pipe system (absorber pipes - collector pipes) there is an absorber medium (E.g. water) which absorbs the obtained heat and transports it to a heat exchanger and/or boiler.

• Which Solar-collector system does exist? Because thermal energy is obtained during day time and most heat is used when it is dark and/or cold, and because the time of obtaining does not coincide with the time of use (day versus night, summer versus winter), the obtained thermal energy must be stored. For this, depending on the installation capacity, the following systems exist: • Day storage Here the obtained thermal energy is stored-accumulated in boilers for daily hot- water consumption and/or small heating installations.