After a year of discussions and evidence gathering, we have this week published the results of a joint inquiry by West of England and Welsh Lib Dem parliamentarians and councillors into tidal power from the Severn. You can find it
here. At the start of the inquiry, our group had a wide range of views on the subject but we were all determined to come with an open mind. We wanted to harness the tidal power of the Severn but wanted to see where the evidence led us on which approach would get the best combination of maximising the renewable energy generated, minimising the environmental downside, getting best value for money and doing most for the local economy.
The more we looked at the 'big barrage' (which would run roughly from Cardiff to Weston), the less convinced we were. The Government now thinks it could be 2030 before this up and running, which is pretty hopeless when we need to cut CO2 emissions much more rapidly than that. The Government estimates that a big barrage would wipe out 80% of the 'inter-tidal habitat', and it's inconceivable that this could be replaced anywhere else. Partly as a result of this, any big barrage would be bound to be bogged down in court action for many years and perhaps further delayed as a result. A big Cardiff-Weston barrage would also blight the Port of Bristol which is not only bad news for the local economy but means freight coming to the UK going to ports which are much further from centres of population and therefore generating many more lorry miles. And a big barrage probably generates two huge power surges a day (generating on the ebb tide only) which can be hard to make full use of, especially if they are not at times of peak demand.
All in all, we felt that relying simply on a big barrage was not the answer. In the end we reckoned the best package would be likely to be:
- a smaller barrage, such as at the 'Shoots' (ie near the Second Severn Crossing) especially if this could be used as the route for a new high-speed rail link between South Wales, Bristol and London;
- to pilot 'lagoons' around the estuary, which would spread the period over which power was generated through the day;
- to fund proper research into 'tidal reef' technology which holds out real hope of getting a better balance between power generation and environmental impact, but is still in its early stages of development;
Any use of the Severn for power generation will involve trade-offs, but we believe that this combination offers the best chance of serious renewable energy in a realistic timescale, whilst producing much less environmental impact than a single huge barrage.