This article presents the behavior of an existing system combining solar collectors and heat pumps at large scale (10'000 living m2, more than 1'000 m2 solar collectors) for space heating and domestic hot water production, focusing on summer period. Ongoing detailed monitoring enables to measure its energy performance. The monitoring results for 2012 show a system SPF of 2.9 (2.6 in winter and 4.4 in summer). The direct solar fraction in summer is lower than 50%, which is low considering the oversizing of the solar collector area for domestic hot water production. The high domestic hot water demand (∼50 kWh/m2/yr whereas the usual value is around 20) can partly explain this low value, but other factors should also be considered. The results presented in this article are part of a research project aiming to assess the relevance of the concept of coupling solar thermal and heat pumps in various types of building (especially existing buildings with low efficient thermal envelope).
Fraga, C., Mermoud, F., Hollmuller, P., Pampaloni, E., & Lachal, B. (2014). Large solar assisted heat pump systems in collective housing: In-situ monitoring results for summer season. In Energy Procedia (Vol. 48, pp. 1086–1095). Elsevier Ltd. https://doi.org/10.1016/j.egypro.2014.02.123