A solar energy utilization system includes a solar panel, a motor driven by an inverter circuit functioning as a motor drive circuit with power output by the solar panel, a solar output voltage monitor functioning as a monitor that monitors an input or an output of the solar panel and also functioning as a monitor that monitors an input or an output of the inverter circuit, and a controller. The controller has a control mode in which the inverter circuit is controlled such that an output voltage of the solar panel is maintained at a voltage higher than a maximum power point voltage. In this control mode, the controller performs the control such that a rotation speed of the motor is changed repeatedly at predetermined timings.