An electrical supply module including: a composite board including an anode layer and a cathode layer of electrically conducting material, which anode layer and cathode layer are separated by an insulator of electrically insulating material, the anode layer and the cathode layer each having a trench extending from a connection surface of the composite board; an adapter for mounting in a hole extending entirely through or partly through the composite board, the adapter including a circuit board carrying an electronic component, the circuit board establishing electrical connection from the anode layer to an anode of the electronic component and electrical connection from the cathode layer to a cathode of the electronic component; and a power supply capable of providing a constant voltage or a constant current between the anode layer and the cathode layer. An electrical supply system including the electrical supply module and an extension module.