A vessel which floats on water and which generates electricity

A floating vessel 2 has a hull 6, at least one water inlet 8 at a front part of the vessel 2, and at least one water outlet 10 at another part of the vessel 2, and apparatus 12 for generating electricity comprising at least one stator 16 and at least one rotor 18 in a channel between the inlet 8 and the outlet 10. The vessel may be a barge, and the outlet(s) 10 may be at a side of the vessel to minimise the length of the fluid channel, and therefore the backpressure generated by fluid flowing through the channel. Doors 26 (and 24, figure 3) may be provided to provide a streamlined shape when the vessel is towed through water. The doors may be sealed so that water can be pumped out of the channels for maintenance or replacement.