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undersea turbine
Cantick Head
Tidal Energy


  The Cantick Head Tidal Development Ltd renewable energy site has been awarded to a joint venture company owned by OpenHydro and Scottish and Southern Energy (SSE).  The site is a three mile stretch along the south coast of South Walls (Hoy) and lies within the Pentland Firth which is considered to be one of the world’s largest single tidal sites. It is claimed that the site will be a major first step in delivering, by means of undersea turbines, large scale tidal energy to the UK; with this one project having the potential to provide enough energy to power over 130,000 homes. Extrapolated from their own published data this would mean that between 850-900 turbines [of the size tested] were required to meet this target

   Over the next few years, the joint venture company says that it will be working closely with statutory bodies, local communities and others to complete the required surveys prior to bringing forward an application to deploy these tidal undersea “open-centre” turbines.   

  Their Open-Centre Turbine is designed to be deployed directly on the seabed and, it is said, will be silent and invisible from the surface.


“Farms” of these turbines will be located at depth and present no navigational hazard whilst providing, it is said, a significant, predictable and undetectable supply of clean renewable energy. 

The developers claim that communities that benefit from power supplied by the undersea turbine technology will never be conscious of the turbines' existence.

undersea turbine 2

open-centre turbine

The open-centre turbine is an example of a simple idea proving to be a most effective solution to renewable energy generation.

The functionality and robustness of such equipment in an underwater environment is crucial. The turbines expect to meet these demands, with a slow-moving rotor (about seven r.p.m) and a lubricant-free operation minimising risk to marine life..

The proposed turbine has a number of design features intended to avoid any impact on marine life. The large open centre, about 2 metres in diameter, provides a safe passage for smaller marine life and the turbine's hydrodynamic lines should ensure that fish will not become entangled.  The minimal underwater noise may prove sufficient to allow larger mammals to detour around the turbines


Currently, no scientific evidence seems to exist concerning the impact of such undersea turbine developments on marine life or the environment.  Nor does there appear to by any planned other than a three year research project, which hopes to determine whether sea mammals can detect noise from the turbines and, thus, can avoid colliding with them.

All we know for sure is that the introduction of undersea turbines (and exclusion of some types of fishing) will bring about some changes for species and habitats, but nobody can say for sure at this point what those changes will be.  Present knowledge – based on offshore windfarms seems to be that there may be some disruption during the installation stage but no evidence of damage to marine life has been witnessed.  The scientific consensus, therefore,  seems to be to install the turbines and then observe the consequences: early results should be available from turbines already installed in the
Channel Islands and Canada.

Turbine information and photgraphs  gathered from OpenHydro website

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