The visitors use (hand) cranks to generate currents that drive various receivers. In order to drive the corresponding receiver, one has to perform different amounts of work. The audience gets an impression of how much work/energy is necessary to drive a certain device, but also that certain performances are only possible with a corresponding receiver. The exhibit may have hand cranks, a running wheel, a bicycle, or a "pedal boat" as a device to generate energy. The energy that can be stored, transformed, transported, or used to power various loads (e.g., a pump).