<p>Methods of using solar energy include solar technology that converts/produces solar energy into electricity using photoelectric devices, and solar technology that stores/produces solar energy in a fluid using a collector. And there is a PVT (Photovoltaic-Thermal) composite technology that can produce electricity and thermal energy simultaneously. In particular, PVT composite technology, which produces electricity and heat using solar energy, is a new and renewable energy convergence technology that combines existing solar energy and solar heat utilization unit technologies, and various studies are being conducted recently. In this paper, we constructed a PVT system that can evaluate the power generation characteristics of electricity and heat energy and compared and analyzed the energy generation amount with a PV system that only generates electric energy. In addition, in order to optimally operate the PVT system according to changes in solar radiation, we studied the control method of the PV inverter standalone operation mode and the combined mode in which the PV inverter and solar thermal equipment operate simultaneously.</p>