The Application of Passive Radiative Cooling in Greenhouses

Abstract

At present, greenhouses are used to grow a variety of crops around the world. However, with the change of climate, the increasingly harsh weather makes it more and more disadvantageous for people to work inside, and plants are difficult to grow. Previous research has illustrated that radiative cooling can be realized by using certain nonmetal oxide particles created for emission in an infrared atmospheric transparency window, which is an environmentally friendly cooling method due to reducing energy consumption. Polyethylene (PE)-based formulations with a UV stabilizer and nonmetal oxide particles (NOP) were first granulated and then formed a monolayer film by co-injection molding. The experimental results show that due to passive radiative cooling, under the environmental conditions of 35 °C, and only considering the natural convection heat transfer, the net cooling power of the greenhouse film developed in this study is 28 W·m−2 higher than that of the conventional PE film. The temperature inside the simulated greenhouse cladded with the new greenhouse covering was on average 2.2 °C less than that of the greenhouse with the conventional PE film.