Most powerful tidal turbine starts generating power

What's being described as the most powerful tidal turbine device in the world has connected to the grid in Orkney.

Orbital Marine Power's O2 tidal turbine is anchored in the Fall of Warness where a subsea cable connects the two-megawatt offshore unit to the local onshore electricity network.

It comes as industry leaders call for government support to help the tidal industry develop commercially.