Feedingelectricity from photovoltaic solar modules into the mains grid requires severalspecial system components. These components enable conversion and capture ofthe solar electricity and ensure system safety. The unit contains thesecomponents and is conceptualized as an extension for the trainer. Thephotovoltaic DC current from is fed to the input of via a connectioncable. Inside the DC current passes safety devices and enters theinverter. The inverter transforms the DC into AC current. The inverter alsooptimizes voltage and current to ensure that the photovoltaivc modules producemaximum possible power. The inverter output provides an AC voltage withappropriate level and frequency to enable feeding into the mains grid. Theamount of fed in electricity is captured by a modern two way electricity meterand the own consumtion is captured by an energy logger.