Author: BBC Radio 4

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 Goodman

Produced 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.

Wind energy is vital in the battle against climate change, but can we make improvements to harness more from them? Tom Heap visits Kelburn windfarm in North Ayrshire to discuss whether 'wakesteering' - reorientating the turbines could see them harness more power collectively. Meanwhile some potential sites are refused or restricted due to the damage caused to wildlife. Hubert Lagrange talks about his childhood obsession with bats which are often killed by the pressure around turbine blades. He's worked to develop a system to sense bat and bird activity and allow the turbines to operate longer through a refined system. Dr Tamsin Edwards discusses how much more potential there is and how much carbon this could save.

Producer: Anne-Marie Bullock Researcher Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Asst Professor Michael Howland from the Massachusetts Institute of Technology and Professor Nick Jenkins from Cardiff University.

Batteries are powering the electric car revolution, but can we make them longer lasting, faster charging and smaller and lighter? Beyond electric cars and other vehicles, the more applications means more renewable energy can be stored and used, driving us away from fossil fuels. Tom Heap visits UKBIC - the UK Battery Industrialisation Centre in Coventry - a vast facility to develop better batteries. He dons full protective gear to see some of the processes involved in making batteries and testing new chemistries and engineering. He speaks to Isobel Sheldon from British Volt about the goals and potential that could be realised by improving batteries and climate scientist Dr Tamsin Edwards assesses how much carbon dioxide this could potentially save.

Producer: Anne-Marie Bullock Researcher Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Solomon Brown from the University of Sheffield and Dr Carlos Fernandez at Robert Gordon University.

How well is your country doing? The GDP - gross domestic product - has long been a measure of growth and success but some argue judging purely on economics is too narrow-sighted. Tom Heap meets 'chopsy' Sophie Howe, the Future Generations Commissioner for Wales who will challenge if a decision being made will be detrimental for children and those yet to be born. If the cost and inheritance to them is high it risks getting kicked out. She takes him to the wetlands she helped save from a planned M4 development. Katherine Trebeck explains alternatives measures of national success, the factors they take in and why many feel happier about using them. Dr Tamsin Edwards assesses what an alternative viewpoint could do for carbon cutting.

Producer Anne-Marie Bullock Researcher Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Lukas Hardt from WEAll Scotland, to Dr Paul Brockway from the University of Leeds and to Dr Chris Hope from the University of Cambridge.

Generating renewable energy from solar power has been a great resource but land for this purpose can come into conflict with other uses or receive opposition from those who don't enjoy the view. But can floating solar panels on water - which accounts for most of the surface of the planet - provide an alternative?

Tom Heap meets Mark Bennett, a farmer from Berkshire, who created a reservoir for soft fruit production and was curious to see if it had more potential. After a quick internet search he went to visit Ciel et Terre, a French company who were developing floating solar panels. He installed them for power at the farm and to demonstrate to others. Meanwhile the company founder Bernard Prouvost talks to Tom about the countries around the world which are adopting this, where he feels floating panels are appropriate and if the potential to partner with hydrodams. Climate Scientist Dr Tamsin Edwards assesses their carbon cutting potential.

Producer: Anne-Marie Bullock Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Tasmiat Rahman from the University of Southampton and Grant Feasey from AES Solar.

There are different schools of thought on how land (and sea) are best managed but often in the rush for economic development indigenous practices and knowledge are overlooked. Observations and understanding from living on the land can inform how to protect and preserve it . Tom Heap meets Victor Steffensen, a descendent of the aboriginal Tagalaka people and an indigenous fire practitioner. He explains how cultural burns can help manage the land, reduce the fuel load and the likelihood of destructive wildfires. Yet he feels while there are calls to incorporate this knowledge more, it doesn't go far enough. Diana Mastracci is a researcher working with groups in the Amazon and Arctic to give them equal participation and benefits from research and runs hackathons for software ideas that could use and value their knowledge more and says academics have a long way to go to fully appreciate this knowledge. Dr Tamsin Edwards weighs up just how much carbon dioxide could potentially be saved by adopting indigenous land management practices.

Producer: Anne-Marie Bullock Researcher Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Jem Woods and Miss Abi Croker from Imperial College London and to Dr Caroline Lehmann from the University of Edinburgh.

To find out more about Indigenous Land Management and Landcare Australia : https://landcareaustralia.org.au/

Flying, for business or pleasure, has long been seen as one of the biggest carbon villains. As airports gear up again after Covid it's clear not every business wants to keep meetings online or holidaymakers settle for a staycation.

But what if we could fly without the guilt? Tom Heap meets some of the pioneers of zero carbon flight: hitching a ride with Harbour Air in Canada who have retrofitted one of their planes to fly on electric battery power; visiting the equivalent of the Batcave with a Bristol company making EVTOLs - electric vertical take-off and landing vehicles - which could see us zipping between cities; and asking about the use of sustainable aviation fuels. Dr Tamsin Edwards joins him to discuss how much carbon dioxide - and more - this could potentially save.

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Andy Jefferson from Sustainable Aviation and Tim Johnson from the Aviation Environment Federation.

Producer: Anne-Marie Bullock Researcher: Sarah Goodman.