Boris Johnson’s supposed “Green Industrial Revolution” is starting to get underway. Chancellor Rishi Sunak earmarked £525 million for the development of large-scale and advanced nuclear technology yesterday, as he laid out how last week’s Ten Point Plan for fighting climate change would be financed. At least some of this money will be heading to the nuclear industry’s latest great hope, a tantalising promise for a more sustainable future – small modular reactors (SMRs).

The only hitch is that they don’t exist yet…