One key question remains unanswered despite the go-ahead for further nuclear power plants: what to do with the waste they will generate.

UK policy is to build a long-term underground storage facility – so-called geological disposal – for future waste as well as that already produced from past and current nuclear sites. Most of this is stored “temporarily” at Sellafield in Cumbria, the country’s biggest and dirtiest nuclear site, now devoted to reprocessing rather than power.