Innovative turbine turns tidal streams into electricity

Chiswick based partnership creates pioneering power generating system

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Chiswick based partnership, TidalStream, have created a ground-breaking new system that uses tidal flow to produce energy. 

Developed by Chiswick resident John Armstrong, former technical director of the Wind Energy Group, and Mike Todman, former chief engineer at Rolls Royce Marine, these innovative underwater generators have the potential to provide at least 5% of the UK’s electricity requirements.

Tidal stream energy has the advantage over wind energy that it is silent, practically invisible, 100% predictable and uses only a quarter of the space.

The TidalStream system uses technology and components developed from the wind industry and is designed to be situated in deep water where currents are at their most powerful.  TidalStream have tested a small turbine in the Thames at Chiswick. 

Each system consists of four turbines, similar to a wind turbine, mounted to a tube-shaped buoy. Flooding the tube with water sinks the buoy, leaving only the top exposed, and puts the turbines into their operating position under water. A long arm connects the buoy to a heavy base that sits on the seafloor. The arm is designed to move up and down and side to side, allowing the turbines to swing with the tidal current. When the tube is emptied of water, it rises up and rolls over on to the surface, so that the turbines are above water and can be maintained or replaced. The novel installation system negates the need for jack-up barges, heavy lifting cranes or divers.

According to Armstrong, 300 TidalStream units, installed in a high current channel such as the Scotland’s Pentland Firth, could provide the power capacity of a 1200-megawatt nuclear plant; energy for half a million households. The partnership is aiming to contribute to a government mandate that requires 20% of the country's energy to come from renewable sources by 2020.


February 3, 2006