The Evacuated Vacuum Tube absorbs Solar Energy and converts it into heat, which can be used for water heating.
Westech use the most common type of evacuated vacuum tube, the “all-glass tube”. This type of tube is chosen because of its reliability, performance and low manufacturing costs.
Why a Vacuum?
As you would know if you have used a glass-lined thermos flask, a vacuum is an excellent insulator. This is important because once the evacuated tube absorbs radiation from the sun we don’t want to lose it!
A vacuum helps to achieve this.
The insulation properties are so good that while the inside of the tube may be 150°C, the outside of the tube is perfectly cool to touch.
This also means that even in cold conditions evacuated tube collectors can perform well when flat plate collectors suffer heat loss.