New design for UK offshore tidal turbines
The Guardian reports, 7th August 2015: A British company has announced plans for an array of unique marine turbines that can operate in shallower and slower-moving water than current designs.
Kepler Energy, whose technology is being developed by Oxford University’s department of engineering science, says the turbines will in time produce electricity more cheaply than off-shore wind farms.
It hopes to install its new design in what is called a tidal energy fence, one kilometre long, in the Bristol Channel — an estuary dividing South Wales from the west of England — at a cost of £143m.
Tidal fence developed by Oxford University spin out Kepler Energy and proposed to be deployed in the Bristol Channel between Aberthaw and Minehead
Picture: Kepler Energy.
The fence is a string of linked turbines, each of which will start generating electricity as it is completed, until the whole array is producing power. The fence’s total output is 30 megawatts (MW), and 1MW can supply around 1,000 homes in the UK.
Peter Dixon, Kepler’s chairman, told Reuters news agency: “If we can build up to, say, 10km worth, which is a very extended fence, you’re looking at power outputs of five or six hundred megawatts. And just to visualise that, it’s like one small nuclear reactor’s worth of electricity being generated from the tides in the Bristol Channel.”
The new Transverse Horizontal Axis Water Turbine (THAWT) — whose design is compared to that of a water mill — will use the latest carbon composite technology, and should be suitable for the waters around Britain, as well as overseas.
Because the turbines sit horizontally beneath the surface of the sea, they can be sited in water shallower than the 30-metre depth typically required by current designs. And because the water is slow-moving, the company says, fish can safely avoid the turbines’ blades.
Although the technology is regarded as environmentally benign, Kepler says it will still undergo a rigorous environmental impact assessment during the planning process to ensure that it poses no significant risk to marine life and to other users of the sea.
Source: The Guardian, 7th August 2015. For the full details, see
www.theguardian.com/environment/2015/aug/07/revolutionary-tidal-fence-set-to-trap-seas-power
