System materials, three-element vacuum tubes:

They are coated glass tubes without air placed next to each other and a thermal insulation vacuum between the tubes. These vacuum tubes are made of borosilicate glass which has a low coefficient of thermal expansion, making it highly resistant to thermal shock. It has high chemical resistance and higher mechanical strength than ordinary glass.

Each tube is equipped with an absorber, which absorbs the solar energy. Due to the vacuum, the heat is reliably retained inside the tubes. The efficiency of the evacuated tube collectors is more than 90%.

Vacuum tubes are called three-element because they have three layers, the first one being anti-reflex and is blue in colour, the second is a layer ofabsorbance and the third layer is areflection layer</strong (red/copper colour).

Technical details:

Vacuum Tube technology:
Models 47mm / 1500mm, 58mm / 1800mm
Weight 1.35kg, 2.29kg
Structure All-glass-coaxial All-glass-coaxial
Double-layer tubes double-layer tubes
Outer tube diameter 47mm, 58mm
Inner tube diameter 37mm, 47mm
Outer Tube thickness 1.6mm, 1,8 mm
Inner tube thickness 1.6mm, 1,8mm
Material of coating Al N/Al N-SS/Cu Al N/Al N-SS/Cu
Absorptance 94% - 96%, 94% – 96%
Emittance 0.04~0.06, 0,04~0,06
Vacuum P≤5*10-3pa, P≤5*10-3pa
Stagnation temperature 270~300, 270~300
Heat-loss coefficient ≤0.6w/ m2), ≤0,6w/ m2)
Bearing hailstone ability 25mm, 25mm
Pressure-endure ability 1MPa (10 Bar), 1MPa (10Bar).