Techno-economic feasibility of heat recovery chillers in subtropical hotel buildings

Abstract

Despite the environmental and economic benefits of heat recovery chillers (HRCs), their advantages are not well-identified, particularly in subtropical hotel buildings. This study investigates the techno-economic feasibility of using HRC systems in subtropical hotel buildings, compared to conventional air-cooled and water-cooled chiller systems. The study employs EnergyPlus simulations to model the performance of the different chiller systems, and assesses the operating costs based on utility tariffs in Hong Kong. The results show that by recovering waste condenser heat for domestic hot water, HRCs can achieve 40.44 % energy savings and 57.12 kgCO₂e/m² annual emissions reduction, surpassing the benefits of solar water heating. HRCs also demonstrate 28.44 % and 10.71 % lower life cycle costs compared to air-cooled and water-cooled systems, respectively, with a 160.94 % return on investment. This research highlights the unique advantages of HRCs in subtropical regions and their potential to drive sustainable and cost-effective cooling solutions in hotel buildings, which have not been extensively explored before.