39 Ways to Save the Planet

It could be the clean fuel of the near future- for homes and for heavy machinery. Lord Bamford, head of JCB, is betting that it will power the next generation of emission-free tractors, diggers and loaders. Tom Heap meets the JCB team and discusses the pros and cons of hydrogen with climate scientist, Tamsin Edwards of King's College, London.Producer: Alasdair Cross Researcher: Sarah GoodmanProduced in association with the Royal Geographical Society. Special thanks for this episode to Mickella Dawkins at Loughborough University and from the University of Edinburgh, Dr Katriona Edlmann, Dr Romain Viguier and Dr Ali Hassanpouryouzband.

Arnold Schwarzenegger is the former governor of California and one of America's most influential green voices. He's also one of the biggest movie stars in the world and a big fan of the innovators, activists and entrepreneurs featured in the previous 39 episodes of this series. In this final programme, the Terminator star discusses his favourite ideas from the series with Tom Heap and looks forward to the crucial climate change talks in Glasgow in November.Producer: Alasdair Cross

Tom Heap discovers fresh ways to quantify greenhouse gas emissions with help from satellites, artificial intelligence and former US Vice President Al Gore.Emissions data from companies and countries can be inaccurate, incomplete or sometimes just plain deceitful. The team at Climate TRACE, led by Al Gore, have devised innovative ways to calculate accurate emissions data from power stations, factories, ships and even planes. That data can be used to reveal unexpected sources of carbon dioxide and methane and to provide independent figures for international negotiations on climate change. Producer: Alasdair Cross Researcher: Sarah GoodmanProduced in association with the Royal Geographical Society. Special thanks for this episode to Professor Raphael Heffron from the University of Dundee and Professor Paul Palmer from the University of Edinburgh. Image courtesy of Transition Zero.

Ever thought about the carbon cost of a packet of crisps? At CCM Technologies they think of little else. Their revolutionary fertiliser offers a big step to carbon-free snacking.Waste from crisp factories or from sewage treatment works can be routed and treated to form the basic building blocks of new fertilisers that can be spread on the ground to grow a new harvest of potatoes- or any other crop we need. The system avoids waste and takes a big cut out of the carbon emissions of traditional fertiliser production. Tom Heap tours the CCM fertiliser plant on the outskirts of Birmingham and discusses the carbon benefits with Dr Tamsin Edwards of King's College London.Producer: Alasdair Cross Researcher: Sarah GoodmanProduced in association with the Royal Geographical Society. Special thanks for this episode to Dr Kate Schofield from the University of Plymouth and Dr Abigail González Díaz from the National Institute of Electricity and Clean Energy.