A passenger control unit is provided that may include a push-button, power assembly, and control and communication circuitry. The push-button may be for control of a passenger service unit (PSU) onboard a passenger vehicle, and may also generate mechanical energy when pushed. The power assembly may convert the mechanical energy to electrical energy, and store the electrical energy, solely from which the control and communication circuitry may be powered. The control and communication circuitry may include a microprocessor and a communications interface. The microprocessor may receive an indication when the push-button is pushed, and generate an instruction to control the PSU in response thereto. And the communications interface wirelessly transmit the instruction to a control unit configured to effect control of the PSU based thereon.