triple-cavity all-glass vacuum heat collection tube

1.structure:all-glass double-tube co-axail structure2.High borosillicate 3.3 glass3.absorptive coating property:   a.structure AL/AL-ALN(H)/AL-ALN(L)/ALN   b.sediment method:single target magnertron sputtering plating   c.specific absorption:0.90~0.93(AM1.5)   d.emission ratio:0.05~0.075(80oC±5oC )4.idle sunning property parameters:Y=220~260m2.oC/KW5.solar irradiation for obtaining a preset water temperatureH=4.14.4MJ/m2(Φ58)  H=3.13.4MJ/m2( Φ47 )6.Average heat loss coefficient:0.6~0.7W/(m2.oC)7.usage life: 15 yearsADDING ONE MORE COMPLETE GLASS TUBE IN THE NORMAL TUBE,RAISING THE HEATING EFFICIENCY BY DECREASING THE WATER CONTENT, NOT THE HEATING AREA. THE HEATING EFFICIENCY CAN IMPROVE 30%BY THIS WAY.
triple-cavity all-glass vacuum heat collection tube