Good tidings

In response to David Cutter (Letters, 4 September) there is a combination wave/tidal device — the Ecofys Wave Rotor — which is designed to attach to wind turbine towers.

However, in general, wind turbines will not be installed in high current areas as the cost and risk of installation is greatly increased by the tides.

Second, wave energy converters tend to favour deeper water (50m plus) where the power is higher and, once again, greatly increases the cost of building and installation of wind turbines.

For those reasons, and the converse that many tidal sites may have lower wind regimes than open sea, it is much less likely that a site suitable for shared development can be found.

An exception may be where a transportation infrastructure can be built incorporating wind and tidal. But even this is unlikely to be a wave area for obvious reasons.

John Griffiths, via e-mail

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