The market for photovoltaic is rapidly expanding and there are some large utility PV power plants, thousands of residential systems, and tens of thousands of remote power systems in use. Even if photovoltaic is a technology that has already demonstrated its effectiveness and holds great promise in electrical generation, the costs are still too high to guarantee a commercial competitivity. This paper presents the performance results of a 15 kWp photovoltaic power plant installed on the roof of a high school in central Italy. The system consists of 220 modules for a total of 22 arrays, which are connected to inverters to allow conventional appliances to be powered by photovoltaic electricity. The PV plant is remotely controlled and data on sun radiation, ambient temperature, modules temperature and power production are continuously acquired by a PC. The measured power plant performances during the year are presented in this paper.