Integration of a latent heat storage in the refrigeration cycle of an air source heat pump for energy-efficient heating, cooling and DHW operations

Description

This work develops a concept to increase the coefficient of performance (COP) for split air-source heat pumps (ASHPs) in residential applications and capable to meet the thermal demands (i.e. space heating, space cooling and domestic hot water). It considers the integration of an innovative three-media heat exchanger that is refrigerant-PCM-water heat exchanger (RPW-HEX). Accordingly, a new design of the refrigeration cycle is developed in which the RPW-HEX acts as desuperheater/storage for DHW during winter and as condenser/storage during cooling operation in summer. Thus, a detailed simulation model is developed considering ASHP, building and water distribution network with different control levels in Dymola. The concept is examined for two seasons; winter whereby space heating and DHW emerge as leading thermal loads, whereas space cooling and DHW are predominant during summer.

The findings showed an increase in COP for space heating and DHW up to 20% compared to a conventional ASHP during winter. For summer, the outcomes revealed a COP improvement leading to a reduction of electricity input by 25% compared to the available concepts. Herein, thermal energy stored in PCM of the RPW-HEX. Later, this heat can be discharged from the RPW-HEX during DHW operation.
Moreover, it is worthwhile to mention that the work also conducts several optimization scenarios to examine the impact of several control strategies for the components included in this system. These investigations will help later in developing operation guidelines for such technologies and impeding any technical challenges that might arise throughout the operation phase. Furthermore, this is also associated with functionality tests in labs in order to gain further insights.

Period	25 Sept 2024
Event title	BauSIM 2024
Event type	Conference
Conference number	10
Location	Vienna, AustriaShow on map
Degree of Recognition	International