It may sound like the stuff of science fiction, but the idea of assembling giant solar farms in space and then beaming the renewable energy back down to Earth is gaining real life traction. Some advocates have claimed it could supply all the world’s energy needs by 2050. But how would these solar farms be assembled, how much fuel and money would it take to blast them into space in the first place, and how would we safely beam their energy back to Earth? Sophie Eastaugh and Luke Jones speak to Sanjay Vijendran, in charge of space-based solar at the European Space Agency, learn about the history of the idea from Rick Tumlinson, founder of SpaceFund, and hear words of caution from Dr Jovana Radulovic, head of mechanical and design engineering at Portsmouth University in the UK. Plus, French astronaut Thomas Pesquet describes life on the International Space Station and how it’s powered. Thanks to the Space Studies Institute for extracts of their interview with Gerard O’Neill. Let us know what you think about the show – email theclimatequestion@bbc.com Producer: Simon Tulett Researchers: Matt Toulson and Graihagh Jackson Series Producer: Alex Lewis Editor: China Collins Sound engineer: Tom Brignell Production Coordinator - Siobhan Reed