The Manchester Bobber's inventive features utilise the rise and fall (or 'bobbing') of the water surface. This movement transmits energy, which is then extracted by the mechanics to drive a generator and produce electricity.
The vision is to have a series of Bobbers working together to generate electricity. One concept which is currently being explored is the use of decommissioned offshore rigs as platforms for the devices.
Take a moment to savor the irony of that last paragraph.