Abstract
The effect of a special multi-layered thermal curtain, referred to as the “Futon screen”, and water heat storage on the heating load of a pipe-framed greenhouse was investigated, through a comparison between two pipe-framed greenhouses; one was a greenhouse equipped with the multi-layered thermal curtain (M-house), and the other was a control greenhouse (C-house). The internal temperature of C-house and M-house, both being without heating, were 2.4 ℃ and 7.1 ℃, respectively, when the outside temperature was 0 ℃. The heating load coefficient of M-house, 1.43 W・m-2・℃-1, was lower than that of C-house, 2.39 W・m-2・℃-1. Further, the consumption of heating oil and the heating load of M-house were both approximately 40 % lower than those of C-house. It was clear that the Futon screen reduced the heating load of the greenhouse by approximately 40 %. With the introduction of the water heat storage, the heat loss coefficient of M-house did not change; however, the heating load coefficient of M-house reduced from 1.43 W・m-2・℃-1 to 0.91 W・m-2・℃-1. Further, the consumption of the heating oil in M-house with the water heat storage was reduced to 36 % that of C-house.
