Abstract: Apparatus (1) for generating hydrogen by means of electrolysis is described. The apparatus (1) includes a housing (2,3) adapted to contain an aqueous electrolyte, in use. A number of electrodes (19, 22) are located within the housing (1) The electrodes (19, 22) comprise a number of cathodes (19) and a number of anodes (22). The electrodes (19, 22) each have a first end portion (21, 18) and each of the electrodes (19, 22) are mounted on a first side wall (24) of the housing at the first end portion (21, 18), so that the first end portions (21, 18) are adapted to be coupled to an electrical power supply (104), in use. The electrodes (19, 22) are in the form of elongate members and are arranged in a linear array such that each anode (22) is separated from an adjacent anode (22) by a cathode (19) and each cathode (19) is separated from an adjacent cathode (19) by an anode (22).

Abstract: Apparatus (60) for supplying power to a hydrogen generator (1) to generate hydrogen for supply to an engine (90) is described. The apparatus (60) includes a power supply circuit and a processor (64). The processor (64) receives an input signal (73), the input signal (73) representing a magnitude of an operating parameter of the engine (90). The processor (64) controls the power supply circuit to change an output current of the power supply circuit for the hydrogen generator (1) in response to changes in the input signal (73).