How is the vacuum tube solar collector made?

In 1970s, the first vacuum tube solar collector was born, which was composed of several vacuum collector tubes. The most commonly used all-glass vacuum tube consists of a large tube and a small tube. The small tube is filled with water. Through chemical treatment, a layer of material is formed outside the small tube to absorb the radiation of sunlight. Vacuum is pumped between the large and small tubes, just like the thermos we usually use, which is not easy to dissipate heat and avoid heat loss. The water in the pipe moves up and down when it is heated. When the sun is strong in summer, the water in the vacuum tube will give off hot air. Because each vacuum tube is an independent power unit, they will generate a lot of heat when combined with each other.

In order to increase the collection of sunlight, some vacuum collector tubes are equipped with reflectors on the back. Generally, vacuum collector tubes can be divided into all-glass vacuum collector tubes, glass U-tube vacuum collector tubes, glass metal heat tube vacuum collector tubes, straight-through vacuum collector tubes and regenerative vacuum collector tubes. This kind of water heater is suitable for hot water in hotels, schools, hospitals, factories, institutions, troops, aquaculture and other places. , suitable for families and villas, and also suitable for hot water in cold areas. In China, more than 95% of solar water heaters are vacuum tubes. Internationally, the export volume of vacuum tube solar water heaters is many times that of flat water heaters.