The aim of this thesis is to study the performance improvement of a hybrid solar PV system with heat-pump thermal storage (HyPV-hp) for storing excess solar PV power to reduce battery. A long-term system performance simulation program was developed to study the design of HyPV-hp and the switching control of heat pump to store excess PV energy. From that, optimal system design can be achieved. A 1.5kWp HyPV-hp was built for field test to verify the simulation results and gather long-term test data. It shows that HyPV-hp is highly economical in use with high-efficiency air condtioners and heat pump water heater.