Severn tidal power schemes: Prepare for a dust-up  

The FT has an article on the slow progress towards deciding what type of tidal power scheme will be built on the severn estuary - Severn tidal power schemes: Prepare for a dust-up

Among the UK government’s raft of carbon reduction plans announced today, it confirmed it will be making a decision on a Severn River estuary tidal power scheme next year.

It will not be easy to get there, however. Few oppose harnessing the Severn’s massive power. The idea has been around for decades - in fact more than a century, according to some reports - because of its high tidal range of up to 11.3m. Located in Britain’s south-west, it is also handily close to people and industry, meaning transmission costs would not be a big hurdle.

The UK government undertook a feasibility study into power schemes using the Severn last year, and decided to provide further funding to five of 10 proposed projects. This decision, however, prompted outrage. Opponents to big barrages have several criticisms: damage to bird habitats, impact on shipping, and unnecessary expense are the main objections.

Cambridge physics professor David Mackay, who examined the UK’s available renewable resources in his book ‘Without Hot Air’, likes tidal power but points out that the while a Severn barrage could theoretically provide current Severn barrage proposals only use energy from the tide moving in one direction, halving its potential.

But a coalition of green groups criticised the choice, saying the government favoured big expensive projects over lower-impact proposals such as lagoons. The government response was that these were the only ones that were realistic, and it had put a smaller amount of money towards ‘embryonic’ approaches such as low-barrage heads, tidal fences and lagoons, which it says have yet to be proven.

The big bad of the schemes, from the critics’ point of view, is the Cardiff-Weston plan which is estimated to cost about £20bn - but would produce an impressive 5 per cent of the UK’s power needs. Of the four other schemes, which range from £2.3bn to £4bn, one would provide 1 per cent and the others, about half of that amount.