Performance Analysis of a Hot Water Supply System with a CO₂ Heat Pump by Numerical Simulation

(1st Report, Modeling and Analysis of Heat Pump)

Abstract

Heat pumps using CO₂ as a natural refrigerant have been developed and are expected to contribute to energy saving in hot water supply. In residential applications, CO₂ heat pumps are used in combination with hot water storage tanks. The objective of this series of papers is to analyze the overall performance of a hot water supply system composed of a CO₂ heat pump and a hot water storage tank by numerical simulation. In the 1st report, a simulation model of a CO₂ heat pump is created based on thermodynamic equations and measured data for an existing CO₂ heat pump. In addition, the performance of a CO₂ heat pump is clarified in relation to the air temperature as well as the inlet and outlet water temperatures.