We should be worried about the flood-proofing of our nuclear power plants, says Sue Roaf , while David Bridgewater argues for nuclear fusion, rather than fission. Plus letters from Dr Kevin Purdy , Dr John Doherty and John Starbuck

In Agneta Rising’s defence of nuclear generation (Letters, 19 September), she claims that nuclear plants have to occasionally stop for repair and maintenance. But jellyfish also get into seawater inlets, as at Torness in 2011, causing week-long shutdowns. Seaweed can block inlets shutting reactors, and operator incompetence shuts reactors and compromises radioactive cores. Torness was even narrowly missed by a crashing RAF Tornado jet. Most worrying are not such transient manageable events but risks of systematic flooding of nuclear sites.

Nine UK plants are assessed by Defra as currently vulnerable to coastal flooding (Report, 7 March 2012), including all eight proposed new UK nuclear sites and numerous radioactive waste stores, operating reactors and defunct nuclear facilities. EDF claims on its website that “to protect the Hinkley Point C station from such events, the platform level of the site is set at 14 metres above sea level, behind a sea wall with a crest level of 13.5 metres”. Hurricane Katrina in 2005 produced a maximum storm surge of 8.5 metres. It is predicted that sea levels may rise by a metre by 2100. The UK government cannot actually have believed in climate change or surely they would not put future generations at such risk? I bet they believe in it now. The question is: do they care? Is it really too late to stop a retrograde, potentially catastrophic and already unaffordable UK nuclear future?

Emeritus Professor Sue Roaf

Oxford

• I accept David Lowry’s critique that nuclear power generation is not uninterrupted or carbon-free (Letters, 18 September), and the need for back-up generating capacity. Gas cannot be the long-term, or even mid-term, solution, however. I am surprised that no mention is made of nuclear fusion as a long-term alternative to fission. A technology of profound challenges, nonetheless it is being actively researched around the world, with China allegedly investing billions in an attempt to lead the world in this.

The UK has an admirable record of achievement in the field, culminating in the Joint European Torus (JET) project. However, costs are huge, hence the establishment of the European Fusion Development Agreement (EFDA) whereby EU nations and Switzerland can share costs, allow full participation and share benefits. Full-scale implementation of this technology is probably decades in development but offers a viable, non-carbon and sustainable support to the burgeoning solar and allied technologies. But will our muddled Brexit exclude the UK from such participation?

David Bridgewater

Pershore, Worcestershire

• Professor Allen and colleagues’ predictions that global warming may be limited are qualified by the proviso that “other greenhouse gases such as methane are controlled” (Global warming goal of under 1.5C can be met, scientists say, 19 September). However, there is no room for complacency in the fight to reduce anthropogenic emissions and to keep warming to an absolute minimum, as recent and ongoing research suggest that any warming at all leads to disproportionately higher natural emissions of these other greenhouse gases (specifically methane and nitrous oxide).

Dr Kevin Purdy

Reader in microbial ecology, University of Warwick

• Following the 2011 Fukushima disaster, Angela Merkel (Who’s the world’s leading eco-vandal? It’s Angela Merkel?, 20 September) closed eight nuclear power plants immediately and ruled that the remainder would close by 2022, instead of 2032. The premature closure of these plants means the construction of nine coal-fired power stations, burning dirty brown coal, with an expected life of more than 50 years.

Dr John Doherty

Vienna, Austria

• In the letters you published about the place of nuclear power in our energy mix, there are no references to the disposal of nuclear waste. Have we forgotten so soon?

John Starbuck

Huddersfield, West Yorkshire

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