Application of transparent insulation materials in improved flat-plate collectors and integrated collector storages

Within the work on new collector designs for the Central European climate, investigations on two different collector systems using Transparent Insulation Materials (TIMs) are presented in this paper. The thermal and optical properties of a polycarbonate honeycomb material are discussed with respect to the design of improved flat-plate collectors and integrated storage collectors with TIMs. Measurements on a collector with this material proved the good collector performance in the temperature range of 80 to 140 degree C. But the collector is not stagnation proof, as the honeycombs start melting at 120 degree C. The paper also describes a collector with newly developed, temperature resistant glass capillaries, with which a stagnation temperature of 261 degree C was measured. Finally, new measurements of an integrated collector storage with polycarbonate honeycomb are reported which confirm the good performance of this simplified solar domestic hot water system.