Solar-Assisted Heat Pump Systems: A Review of Existing Studies and Their Applicability to the Canadian Residential Sector

Combining solar thermal collectors and heat pumps into a single solar-assisted heat pump (SAHP) system is a promising technology for offsetting domestic hot water (DHW), space-heating, and cooling loads more efficiently. Task 44 of the Solar Heating and Cooling (SHC) Programme of the International Energy Agency (IEA) is currently investigating ways to optimize solar and heat pump systems for residential use. This paper presents a review of past and current work conducted on SAHP systems. Specifically, the key performance data from many studies are highlighted and different system configurations are compared in order to establish insight toward which system configurations are suitable for the Canadian residential sector. It was found that the most suitable configuration for Canadian residential buildings depends on a combination of factors which include occupant behavior, building characteristics, operation parameters, system components, and climate. A large variety of configurations and parameters exist and this made analyzing a specific system, comparing differing systems and establishing an optimal design difficult. It was found that different authors used different performance criterion and this inconsistency also added to the difficulty of comparing the studies of different systems.