A solar polygeneration system was studied for a multi-family building in Algeria. The system uses solar panels, a heat pump, and a chiller to provide heating, cooling, hot water, and electricity. Simulation results show the solar system can cover over half of the building's yearly heat and electricity needs. It saves 37.1 MWh of energy annually, which is 39% of what a traditional system uses. However, the high cost of solar panels makes the system economically challenging, with a payback period of over 55 years. The system's performance is greatly affected by the size of the solar panels, system cost, and electricity price. It becomes cost-effective when the panel cost is 400 €/m² and electricity costs 0.12 €/kWh. The system works best in areas with high solar potential and energy needs.