This paper concerns the evaluation of a 500 kW solar assisted heat pump system with combined ice storage installed on “La Cigale”, a 19'000 m2 retrofitted multi-family building complex situated in Geneva. The presented results are based on a detailed monitoring campaign, covering a full year of operation, in real use conditions. After presenting the system concept, the system performance is analyzed by way of a detailed Sankey diagram (heat and electricity flows between the various production units, heat storages, and demand units), along with specific analysis of the diverse sub-systems. As a complement to the monitoring results, we present a simulation tool that was specifically developed for this type of application, and its validation against monitoring data, in terms of annual values and monthly profiles of the diverse energy flows.