... absorption is 92%, reflection reduces 65% heat increases 12% Higher temperature Solar Evacuated TubeJust like an automobile engine, the computer CPU, vacuum ... alkali proof above Grade 2. It can resist the hailstone with Diameter 25mm, resisting pressure 1MPa.4. Reducing the fouling ... on the tube wall, keeping water clean.5. Vacuum tubes are aligned in parallel, the angle of mounting depends upon ...