An offshore wind turbine erected in a body of water including a generator, a base, a nacelle, a tower having a first end mounted to the base and a second end supporting the nacelle, an electrolytic unit electrically powered by the generator to produce hydrogen from an input fluid, in particular water, and a fluid supply assembly for supplying the input fluid from a fluid inlet arranged below a water level to the electrolytic unit arranged above the water level, wherein the fluid supply assembly includes a pump and a fluid connection between the fluid inlet and the electrolytic unit.