China's current use of
solar collectors can be simply divided into two categories: flat-plate solar collectors and vacuum tubes (including the all-glass vacuum tube and heat pipe vacuum tube) type solar collector. Flat-plate solar collector applications earlier, with the lighting area, the structure is simple, safe and reliable operation, low investment cost, easy maintenance, long life, has been used in domestic hot water supply, heating and air conditioning engineering, engineering dehumidification, warm water aquaculture and other fields. But the heat flux is low, the working fluid temperature is low. The flat-plate collectors do not have the condenser function, and its working temperature is generally limited to below 100 ℃.
All-glass vacuum tube solar collector structure is simple, mature technology, reliable, and glass materials accessible, cost-use year in and year as the volume, with transmission and absorption rate, heat-reflective low convection heat loss is small and a long time throughout the year other fine features, all-glass vacuum tube solar water heater solar water heater in China accounts for 70%% of total production. The disadvantage is that the fragile glass, transportation and maintenance is relatively higher, and can not be confined, at present prices are still high, the engineering application of a longer payback period.
