Scotland will see the world's largest tidal arrays constructed, as the first large-scale rollout of tidal energy generation is planned off the coast
Scottish Power is planning on building two farms of turbines off the Scottish coast after a trial with one 30m turbine, the HS1000, anchored to the ocean floor in a fast-flowing channel near the Orkney Islands, raised one megawatt of electricity - enough to power around 500 homes.
The project at the Sound of Islay should hopefully generate 10MW, and then the later project off Duncansby Head should generate around 95MW.
While individual turbines have been trialled across the world, the arrays will be the largest of their kind, with local communities having their power provided by renewable tidal sources.
Consideration for wild plants and marine life means the blade speed is restricted and the turbines must be located in areas where there is a reliably fast current travelling at least 2.5m/s.
The turbines are between 40 to 100 metres below the surface of the sea and pose no danger to shipping.
The turbines are designed to turn in both directions to generate power, giving a constant supply of electricity.
Scottish Power estimates the cost of the turbine farm to be around £70m.
In 2009 Scottish Power announced plans for a new gas-fired power station in Kent, which will cost £500m but will produce 1,000 megawatts of electrical energy compared to the 10 of the undersea turbine.