Solar Spa - Solar Vacuum Tube EVACUATED TUBE
EVACUTED TUBE absorb solar energy converting it into heat to boil water. Each EVACUTED tube consists of two glass tubes made from extremely strong Borosilicate glass. The outer tube is transparent allowing light Ray's to pass through with minimal reflection. The inner tube is coated with a special selective coating which features exnt solar radiation absorption and minimal reflection properties. The top of the two tubes are fused together and the air contained in the space between the two layers of glass is pumped out while exposing the tube to high temperature. this evacuation of the gasses forms a vacuum, which is an important factor in the performance of the evacuated tubes.