The rejected Welsh tidal power scheme is a missed opportunity on many fronts, says the chair of the planning inspectors who studied the proposal

The rejection by ministers of the proposed Swansea Bay tidal lagoon (Report, 26 June) must be the final nail in the coffin of what was once claimed would be “the greenest government ever”.

When I and my fellow planning inspectors spent the best part of a year examining and reporting on both the principle and the detail of the project in Swansea, it was clear that this pathfinder project had important environmental, cultural and regeneration benefits.

Vitally, it would provide baseload generation capacity to complement our welcome but increasing reliance on wind energy. In addition, while being “first of a kind” presents big investment and consenting headaches for a promoter, the potentially infinite lifespan of the generating station means these early upfront costs need to be discounted over a much longer timeframe than other projects.

Failing to weigh these benefits and costs in the Treasury economist’s balance sheet is a major mistake and one that misses a massive opportunity to put the planet back at the centre of our nation’s future.

The recommendation that my panel made to the secretary of state was to consent to the project, and consent was granted. Sadly the government’s ultimate failure to follow through is also a failure to wake up to the urgency of the climate challenge that faces us. We need a government willing to drive this project forward for the sake both of energy security and of the planet.

Gideon Amos

Chair, Tidal Lagoon Swansea Bay Panel of Inspectors 2013/14

• On the day that parliament endorsed the utter folly of a third runway at Heathrow (Report, 26 June, the government rejected plans to build a superb clean energy tidal lagoon in Swansea Bay.

In Britain we don’t have a lot of sun or wind, but we do have enormous tides on our western coasts, capable of generating huge amounts of free power for up 14 hours a day in a totally predictable pattern. We should have built a Severn barrage decades ago. Yet those in charge have decided to pass up an opportunity to generate clean power for generations to come. The sea walls involved should last for hundreds of years if properly constructed – as those of Cherbourg Harbour (completed 1853) and Portland Harbour (completed 1872) demonstrate.

The French are ahead of us here: their tidal power station on the Rance in Brittany has been running since 1966, producing a peak power of 240 MW with an average of 57 MW.

Anthony Curtis

Cavendish, Suffolk

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