By Adam Vaughan Boris Johnson spoke about climate change, green technology and science at the Conservative party conferenceBloomberg/Getty Images Boris Johnson has said the UK can become carbon neutral by the middle of the century and “beat the sceptics”, in his speech to the Conservative party conference. The prime minister touched repeatedly on climate change, green technology and science in his address, and suggested nuclear fusion – which the Tories promised £200m in extra funding over the weekend – was on the brink of a breakthrough. “They are on the verge of creating commercially viable miniature fusion reactors for sale around the world,” he said of the JET fusion research centre at Culham in Oxfordshire. Advertisement “Now I know they have been on the verge for some time. It is a pretty spacious kind of verge,” he joked, to laughter in the audience. While the UK is considered a world leader in fusion research, its continued role in a multibillion European fusion project in France has been called into question by Brexit. ‘Definitely a stretch’ In response to Johnson’s speech, Tom Nicholas of the University of York says: “I would say that’s definitely a stretch.” Culham’s best case would be full technology demonstration by the 2040s, he adds, though even that would not be a commercially viable fusion plant. Johnson said that while people used to suggest wind and solar power were not fit for the UK, on some days they were now supplying more than half the country’s electricity needs. People years ago said “wind turbines would not pull the skin off a rice pudding,” Johnson said. He did not mention the phrase was his own, which he used when he told The Telegraph in 2013 the UK should back shale gas, not wind power. Solar power has stalled in the UK and onshore windfarms are no longer being built on the mainland because of policy changes brought in by the Conservative government in 2015. Battery gigafactory The prime minister also said the UK was leading on low carbon and battery technology, and said the UK would build a ‘gigafactory’, a reference to the sort of large scale battery factory Tesla has built in the US. The Labour Party used its conference last month to promise three such gigafactories. Battery industry figures have told New Scientist the UK is an unlikely candidate for such a facility in Europe, with Germany seen as a much more likely location. Johnson also promised more “zero emission” buses and better road and rail links, though he notably did not mention the High Speed 2 rail project, which is under a government-commissioned review. The prime minister praised UK leadership in science, saying Manchester led on genomics, gene therapy was being used to cure blindness, and the UK was building two spaceports, one in Newquay and Sutherland. More on these topics: climate change politics nuclear fusion technology