Comprehensive test of ultra-efficient air conditioner with smart evaporative cooling ventilation and photovoltaic

Abstract

Going by current usage trends, the use of room air conditioners will increase by three times by 2050. Therefore, it is necessary to investigate an ultra-efficient air conditioner with extremely low operating energy consumption to realize the goal of climate change, especially in the (sub) tropical area. In this paper, an ultra-efficient air conditioner with smart evaporative cooling ventilation and photovoltaic is proposed, which is composed of a highly efficient air conditioner, a fresh air ventilator with evaporative cooling, an evaporative condenser, and a photovoltaic. The mechanical vapor compression system adopts a gas-injected vapor compression cycle with relay cooling, which adapts to extremely high temperatures and harsh environments. Fresh air ventilation, water usage, and indoor temperature/humidity control strategies are also proposed. In the 31-day field test, the independent ventilator operation hours accounted for approximately 38.4% of the total test period. The electricity savings reached 89.8% as the indoor temperature and humidity satisfied all requirements. Through a typical 10-day lab-simulated year-round performance test, the calculated annual power consumption of the ultra-efficient air conditioner was 746.2 kWh, which was 82.8% lower than that of the baseline prototype. Based on the Indian Seasonal Energy Efficiency Ratio test, the calculated results revealed a consumption of 8.43 kWh/kWh, an improvement of approximately 140.7%. The comprehensive electricity-saving rate was 84.1%. The developed prototype won the global cooling prize since it will counterbalance the booming of residential cooling demand in the future, demonstrating a reliable route for energy savings for room air conditioners.