Modelling and Analysis of Building Optimisation and Solar thermal Cooling System in Nepal
Abstract
Space cooling and air conditioning becomes more important as the energy demand for cooling increases rapidly and the increasing frequency and intensity of heat waves become threats, entailing that cooling is not only a matter of comfort, but of health. The demand for cooling appliances in Nepal is rising sharply, which is due to both the effects of global warming and the growing purchasing power of the population. This study investigates treatment of space cooling demand for an office building the humid subtropical climate of Nepal using TRNSYS18 simulation software. Different measures to lower the building cooling energy demand through building optimisation are considered in the first place and then the coverage of cooling demand by solar-based cooling systems. Results show, that the annual sensible cooling demand can be cut by 50% through building optimisation. A solar thermally driven absorption chiller is capable to keep the indoor air temperature below 30 °C at 96% of the time with a maximum temperature of 34.6 °C with a SEERth of 0.79. Adding an electric driven vapour compression chiller increases this number to 100% with a maximum indoor temperature of 29.6 °C and a reduced SEERth for the absorption unit at 0.67. The electric efficiency of the hybrid system on the other hand is characterised by an SEERel of 14.51.