Your article on Hinkley Point C outlines the rising costs, long delays and the mental health crisis among the employees building this new nuclear power station (Report, 14 August). The article suggests the much-delayed project may be delivered around 2025-6. But even this assessment should be treated with real caution. An identical reactor being built at Flamanville in France, which was started in 2007, was supposed to open in 2012. The French nuclear regulator has now sought more work on faulty welds across the reactor, meaning another three-year delay until 2022, ie 15 years after construction began. The additional costs of building this reactor will burden EDF further and inevitably impact on Hinkley Point C. I agree with the National Infrastructure Commission that the costs and delays to new nuclear are such that the UK has to refocus on more deliverable and cheaper renewable energies. Across the board these are being delivered now and we simply do not have the time to wait for new nuclear to come forward. Let’s go for an expansive renewable energy system, backed up with energy efficiency and energy storage. The climate emergency is too pressing to take our time with such endeavours.

Councillor David Blackburn

Chair of UK & Ireland Nuclear Free Local Authorities Steering Committee

• Professor Neil Hyatt (Letters, 8 August) suggests that we should be actively considering doing something with our existing nuclear waste. There is something that could be done to make the problem much easier to solve, and also provide a way of generating power that is free of CO 2 emissions.

Between 1984 and 1994, Argonne National Lab in the US was working successfully on a project called the integral fast reactor (IFR). Like the molten salt reactor (MSR) pioneered by Oak Ridge National Lab, it was inherently safer than the light-water reactors used in most power stations of the time, and it also used up a much higher proportion of its fuel. It could use spent fuel from conventional reactors as its fuel, and in so doing, it converted the “waste” into something that only needed to be stored for a few hundred years, rather than thousands of years.

Unfortunately, the project was shortsightedly cancelled by the Clinton administration. It is good that the MSR is again being actively pursued by various groups around the world, but the IFR also needs to be reconsidered. You can read about it, and much more, in the free online ebook Prescription for the Planet, by Tom Blees. For a more technical write-up, there is Plentiful Energy by Charles E Till and Yoon Il Chang, who were key workers on the project.

Mike Ellwood

Abingdon, Oxfordshire

• The sudden energy failures (Report, 13 August) are a result of capacity problems, namely the phasing out of tried and tested coal-fired stations. By all means bring on renewables but keep the tried and tested on stream to come into their own for the events we have just witnessed. Capacity problems also inflate prices. It is imperative that proposed closures of remaining coal-fired stations such as the iconic Fiddlers Ferry in Warrington are cancelled or at least suspended.

John Barstow

Pulborough, West Sussex

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