We describe a photovoltaic power generation system, the system comprising: at least two photovoltaic panels each having a dc power output; a power conditioning unit having a dc power input and an ac mains power supply output for delivering an ac mains supply; wherein said dc power outputs of said at least two photovoltaic panels are connected in parallel with one another to said dc power input of said power conditioning unit; wherein said power conditioning unit comprises a dc-to-dc converter having an input coupled to said dc power input and having an output coupled to a dc link of said power conditioning unit, a dc-to-ac converter having an input coupled to said dc link and having an output coupled to said ac mains power supply output, and an energy storage capacitor coupled to said dc link; wherein said power conditioning unit is configured to perform maximum power point tracking (MPPT) responsive to a level of power flowing into said dc power input, and wherein said level of power flowing into said dc power input is sensed at said dc link.
