Thermal performance and energy cost of Korean multispan greenhouse energy-saving screens

Protected agricultural system such as a greenhouse cultivation is increasingly replacing traditional farming systems. Nonetheless, high energy demand in greenhouse farming requires innovative technologies through the use of climate screens to ensure sustainable production. Thus, this study developed a novel methodology for examining the energy retention capacity and economic effectiveness of greenhouse climate screen materials using their thermophysical, radiometric and aerodynamic properties in TRNSYS software. The TRNSYS model was developed to determine the energy consumption, which was validated using a multi-span Venlo-type experimental greenhouse (Yeoju, South Korea). Further analyses on energy saving capacity of different screens and the equivalent energy costs were performed. The results from this research showed that among the fifteen investigated screens, the ensemble screen (M3) saved 34.09 kWh.m⁻² of annual energy, equivalent to 60 % of the heating energy demand, and energy cost of 4490.26 Korean won. m⁻². Further, the results revealed that the climate screens with multi-layer, thermoreflective, low longwave transmissivity, impermeable and aluminized strips or surface characteristics and features have a considerable impact on reducing greenhouse energy use and desirable for high energy-saving. This research has demonstrated that the techniques and methods utilised can investigate all the types of covering and thermal screens used in greenhouse.