39 Ways to Save the Planet

Tom Heap introduces Rare Earth, a programme exploring major stories about our environment.

Can British farmers transform themselves into carbon-cutting heroes? Arable farmer, Duncan Farrington has worked hard to reduce the carbon emissions from his farm. He's replanted hedges and trees and cut down on diesel-powered machinery. He's even persuaded some of his staff to cycle to work. But Duncan's farm isn't just zero carbon, it's actually sucking in and locking up vast quantities of carbon dioxide from the atmosphere.

Duncan explains to Tom how he's transformed the management of his soil and proven to doubters that commercial British arable farms can play their part in cutting the planet's carbon emissions.

Producer: Alasdair Cross Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Dr Adrian Williams of Cranfield University and to Professor Andrew Barnes, Professor Mads Fischer-Moller and Professor Bob Rees of Scotland?s Rural College (SRUC).

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 Goodman

Produced 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 Goodman

Produced 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 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.

Nuclear power should be a powerful ally in the fight against climate change but cost and safety issues hold it back. Could a new generation be safer and cheaper? Tom Heap meets the team behind the molten salt reactor that can use nuclear waste as fuel and is claimed to be significantly cheaper and safer than current reactors.

Ian Scott was a senior scientist at Unilever, pioneering research into skin-ageing, but when he retired from the field of biological sciences he became fascinated by the costs of nuclear power. Why had nuclear electricity- which we'd once been promised would be 'too cheap to meter'- become one of the most expensive forms of energy generation. The answer lay with the safety mechanisms that have to be built-in to reduce the risk of another Chernobyl or Fukushima. If he could develop a system that would be much safer then it would, almost certainly, be much cheaper.

Scott's central idea- to use molten salt as a coolant rather than water- caught the eye of energy authorities in Canada and Ian's company, Moltex, has plans to build its first reactor in New Brunswick. Significant safety concerns remain, with some in Canada concerned about Moltex plans to use spent fuel from conventional reactors and others raising fundamental issues about the corrosive qualities of molten salt and the generation of radioactive tritium

Tom visits the Moltex laboratories and climate scientist, Tamsin Edwards, gauges the potential impact on greenhouse gas emissions.

Producer: Alasdair Cross Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Ian Farnan and Dr Eugene Shwageraus from the University of Cambridge.

Biochar is an idea thousands of years old but one that seemed to have been (foolishly) lost by many along the way.

Like charcoal, biochar is made by baking wood in the absence of oxygen and then quenched. It can then be ground down and worked into the soil to improve fertility and crop yields. It's believed to have been applied thousands of years ago in the Amazon, to generate the Terra Preta.

The biochar locks in much of the carbon captured by the trees and stabilises it. Tom meets Forester Dave Faulkner and his team at Whittlewood to see the productions process in Northamptonshire.

Meanwhile, Josiah Hunt experimented with the process in Hawaii and now supplies across California. As well as capturing carbon and improving the soils, he says they're removing liability wood to reduce forest fires and are helping to produce green electricity.

Can this ancient process help bring new hope?

Producer Anne-Marie Bullock Researcher Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Stuart Haszeldine and Dr Ond?ej Ma?ek from the University of Edinburgh and the UK Biochar Research Centre.

Concrete blocks are the foundations of the modern world but they could be greener. Tom Heap meets Colin Hills and his team turning waste dust and carbon dioxide into building materials.

Professor Hills of the University of Greenwich has developed a technique that mimics natural processes, using carbon dioxide as a glue to form stone aggregates from waste dust left behind by heavy industry. The spin-off company, Carbon 8 Systems, has compressed the process into a shipping container and now makes building materials in the UK and France with this clever carbon-munching technique. Colin's colleague, Nimisha Tripathi wants to adapt the system for the developing world, choosing waste from her native India- things like pistachio shells and banana skin- to make a tailored range of building products relevant to the region in which they're made.

Tamsin Edwards of King's College London joins Tom to consider just how much carbon dioxide we can remove from the atmosphere by developing this new generation of bricks and mortar. Producer: Alasdair Cross Series Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Paul Fennell and Dr Rupert Myers of Imperial College London and to Professor Karen Scrivener of École Polytechnique Fédérale de Lausanne.

How to improve mass catering for the planet. Tom Heap considers how changing the menus in schools, hospitals and the armed forces could help in the fight against climate change.

Andy Jones, chair of the Public Sector Catering 100 Group, explains how his own farming family background informs his drive to reduce the amount of meat served in canteens and increase the choice of vegan and vegetarian options. Tom visits hospitals in Nottingham to see the drive in action and joins climate scientist, Dr Tamsin Edwards to consider the carbon impact of a broader shift from beef to beans.

Producer: Anne-Marie Bullock Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Rosie Robison from Anglia Ruskin University and to Dr Tara Garnett and Dr Peter Scarborough from the University of Oxford.

From clothes to cars and buildings, all our new 'stuff' takes energy and resources to produce. If we want to cut down the use of high carbon materials like steel and cement then we need a new attitude. We need to think about sharing more and valuing what we have, we need products that are designed to last longer.

Tom Heap meets Aisling Byrne from clothing app NUW. Concerned about the impact of fast-fashion on the environment, she found that lecturing friends who loved fashion didn't change their minds or behaviour, so she's designed a clothes-sharing app for people to put unwanted clothes into new hands and get the excitement of something 'new' in return. It can stop the demand for brand new products at the top end and avoid landfill at the other end. Professor Julian Allwood of Cambridge University expands on how much our desire for bigger and better is impacting on resources and how behaviour change needs to come sooner rather than later.

Producer: Anne-Marie Bullock Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Mike Tennant of Imperial College London, Dr Sonali Diddi of Colorado State University, Professor Jana Hawley of the University of North Texas and Professor Sandy Black of the London College of Fashion.

A big weight and a very, very deep hole. The team behind Gravitricity think they have found a solution to a serious problem with renewable energy. As we rely increasingly on wind and solar energy the risk rises of the lights going out when the wind doesn't blow and the sun doesn't shine. We can solve the problem with energy storage but batteries are expensive and don't last very long. As Tom Heap and Tamsin Edwards hear, the answer could lie with a deceptively simple pulley system. Put an enormous weight at the bottom of a mineshaft. When you have lots of wind or sun, use the electricity to pull the weight to the surface. When you're short of power, release it and send a huge surge of energy back into the grid.

Producer: Alasdair Cross Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Stephen Peake from the Open University and Dr Hugh Hunt from the University of Cambridge.

Heating our homes can be expensive and draughty old housing stock leaches carbon dioxide. But making homes more energy efficient can be a costly upheaval and is therefore often done piecemeal. Tom Heap meets the team from Energiesprong who are proposing a new model - retrofitting modern technology like insulating 'wraps' around the house, replacing roof tiles with solar panels and fitting ground source heat pumps into old housing stock. It's done on scale and on a whole-house basis to keep costs down with the aim of creating net zero energy homes but also to create 'kerb appeal' so that neighbours will want to 'keep up with the Joneses'. Tom is joined by climate scientist Tamsin Edwards to discuss whether tackling inefficient, poorly insulated housing head-on can provide great gains for people and planet.

Producer: Anne-Marie Bullock Researcher: Sarah Goodman

Made in association with the Royal Geographical Society. Special thanks for this episode to Kate De Selincourt, Professor Stephen Peake from the Open University, Professor Gavin Killip from the University of Oxford and John Palmer from Passivhaus Trust.

Soil is brilliant at capturing carbon dioxide and keeping it out of the atmosphere. But what if we could make it do an even better job? On a farm overlooking the broad River Tay in Perthshire they've sprinkled the fields with the waste product from quarrying. Nature does the rest - using the rockdust to pull carbon dioxide from the air and store it in the soil. With the help of Rachael James from Southampton University, Tom Heap and Tamsin Edwards check out a technique that could be applied to millions of hectares of the world's farmland.

Producer: Alasdair Cross Researcher: Sarah Goodman

Made in association with the Royal Geographical Society. Special thanks for this episode to Professor Heather Viles of the University of Oxford, Professor Larissa Naylor and Dr Adrian Bates from the University of Glasgow, and Dr Phil Renforth of Heriot-Watt University.

Giant fans are sucking in fresh air from the Swiss Alps and Iceland's frozen interior, capturing the carbon dioxide and turning it into fizzy drinks or burying it deep underground. Tom Heap gets up close to the extraordinary Climeworks device at the Science Museum in London and talks to the team that's developed it to ask if they've designed the solution to climate change or created a potent symbol of our failure to cut carbon emissions? Dr Tamsin Edwards of King's College London joins Tom to crunch the numbers.

Producer: Alasdair Cross Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Samuel Krevor and Professor Nilay Shah of Imperial College London and Professor Jon Gluyas of Durham University.

Why use gas or electricity to heat your water when the power of the sun will do it for free? Faisal Ghani, a young Bangladeshi-Australian engineer, has invented a deceptively simple glass pyramid that takes cold water in at the bottom and supplies hot water from the top. He believes it can bring cheap, hot water to every home around the Equator. In the first of a new series packed with carbon-busting ideas Tom Heap visits Faisal at his Dundee production line to hear about his plans to bring hot showers to the world. Climate scientist, Dr Tamsin Edwards of King's College, London, helps Tom calculate just how much carbon hot water from the sun can save.

Producer: Alasdair Cross Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Nazmi Sellami of Robert Gordon University, Professor Chris Sansom of Cranfield University and Professor Henning Sirringhaus from the University of Cambridge.

Fast-growing bamboo has gone in and out of fashion but is now being seen as a possible climate hero. Its capacity to absorb carbon is enhanced by how densely it can be grown, the speed and its regrowth after harvesting - a great advantage over trees. Tom Heap meets Arief Rabiek from the Environmental Bamboo Foundation based in Indonesia. He's working to restore degraded land by planting bamboo which can be managed by communities on a forest to factory system. The harvested product can be used for building structures and furniture through to vases baskets and clothing. He wants to expand the project to nine other countries to bring economic and environmental benefits but are some uses better than others? Dr Tamsin Edwards helps evaluate the scope of bamboo as a solution.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor Vincent Gauci of the University of Birmingham.

Cattle emit huge quantities of planet-warming methane. But they can be stopped! Tom Heap meets Eileen Wall from SRUC, Scotland's Rural College who introduces him to a host of cunning carbon-cutting ideas- from seaweed in the feed and gas masks for cows to barns that can convert methane into energy to power the farm.

Tom is joined by Tamsin Edwards of King's College, London to calculate just how much difference these ideas might make to our warming Earth. Are those the best answers or should we all be persuaded to cut our meat consumption?

Producer: Alasdair Cross

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor Vincent Gauci of University of Birmingham and to Dr Michelle Cain of Cranfield University.

Is logging always bad for the planet? A team from The Nature Conservancy in the United States believe they have developed a way to cut down the trees we need for construction without damaging tropical forests or adding to our carbon emissions.

Tom Heap meets Peter Ellis, the man behind Reduced Impact Logging, and his Indonesian colleagues, Purnomo and Ruslandi, who are persuading the foresters of Borneo to take up the new techniques.

Back in the UK, climate scientist, Tamsin Edwards joins Tom to crunch the numbers- how much carbon dioxide could these ideas save?

Producer: Alasdair Cross

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor David Coomes from the University of Cambridge and to Professor Michelle Pinard and Professor David Burslem from the University of Aberdeen.

While at sea or in port, the hull of a ship can be an attractive new residence for all sorts or creatures. The initial slime build-up can provide a welcome mat for more and more creatures. This 'biofouling' can end up being inches think and heavy in weight as well as stopping the streamlining of the vessel. The drag caused can result in more fuel being needed to keep the ship moving forwards at the same speed - more cost and more carbon.

Tom Heap meets a new stowaway on ships which will help fight the build up. Paint company Jotun has now developed the Hullskater robot. Monitoring of conditions will alert when the robot needs to be deployed on missions - with its magnetic wheels and high definition cameras it inspects the surface and uses brushes to remove the build up.

With an increasing fleet of ships, Dr Tamsin Edwards from Kings College London also reflects on other measures to keep hulls free of build up and alternative fuels that might help the international fleet reduce its carbon impact.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor Bharathram Ganapathisubramani from the University of Southampton.

There are already examples around the world where the manufacturer helps to pay for the safe disposal of waste from their goods once used - such as electronic items or bottles. But what about the carbon dioxide produced from fossil fuels?

Tom hears about the 'Carbon Take Back Obligation' concept - in which oil and gas producers would have to capture and store C02 - ratcheting up from 1% of what they produce by 2023, to 10% in 2030 and 100% by 2050. Some say it's impossible to meet the aims of the Paris Climate Agreement without it.

But where would all that carbon dioxide go? How much storage space would we need for it and how much of the cost would trickle down to the petrol pump?

Dr Tamsin Edwards of King's College, London, armed with statistics gathered by the Royal Geographical Society, joins Tom to add up the numbers.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor Stephen Peake of the Open University and Dr Chris Hope of the University of Cambridge.

For more information on the Carbon Take Back Obligation www.carbontakeback.org

Modern civilisation is quite literally built on steel. Our cities, our homes, our cars are unthinkable without it. But steel-making is the biggest industrial emitter of carbon dioxide so the search is on for a clean, green method of turning iron ore into steel.

Tom Heap meets the Swedes who are ahead of the pack. Three local companies- Vattenfall, LKAB and SSAB- have come together to deconstruct the whole process and develop ways to remove fossil-fuels from each stage of steel-making. From the enormous iron ore mines of Arctic Sweden to the smelters and furnaces that produce the steel, carbon dioxide emissions are being radically reduced, but how close can they get to a truly green steel?

Tom and Dr Tamsin Edwards discuss the Swedish plans and calculate just how much of this industry's emissions could be wiped out in a generation.

Producer: Alasdair Cross

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Chris McDonald of the Materials Processing Institute.

Photo courtesy of: Åsa Bäcklin and HYBRIT

There's a lot of carbon locked up in the peatlands of Britain and Ireland but many of them have been drained for agriculture and dug for fuel or garden compost. The loss of water resulted in the massive loss of carbon to the atmosphere. Rewetting the bogs can not only stop that leaching of carbon but potentially help the bogs sequester carbon once more. Could these once forboding 'creepy' habitats be something of an underrated super solution? Tom Heap speaks to peat expert, Florence Renou-Wilson of University College Dublin, and takes a virtual tour of a new carbon farm - designed to harvest carbon back from the atmosphere. Dr Tamsin Edwards from Kings College London assesses the potential of this solution.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor Christopher Evans of the UK Centre for Ecology & Hydrology and Mike Peacock of the Swedish University of Agricultural Sciences.

When the cod disappeared from the Grand Banks of his Newfoundland home, fisherman Bren Smith saw the light. He realised that we need a new relationship with the oceans- the age of the hunter-gatherers was over and the time of the ocean farmers had begun. After many years of trial and error he developed a new farming system that produces thousands of tonnes of shellfish and edible seaweed, cleans the oceans and absorbs our carbon emissions.

Tom Heap meets Bren and takes a trip to the seaweed farm of the Scottish Association for Marine Science to see if the new techniques in ocean farming can be replicated around the islands and sea lochs of the west coast of Scotland.

Dr Tamsin Edwards of King's College, London, joins Tom to calculate just how much of our carbon emissions might be swallowed by farming the oceans.

Producer: Alasdair Cross

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Professor Jennifer Smith of the University of California San Diego and Professor Michael Graham of San José State University.

There's a dirty secret around the back of your fridge. The world's freezers, fridges and air conditioning units are chilled by gases that have planet-warming properties that are hundreds or even thousands of times more powerful than carbon dioxide. Disposed of properly they're not a problem but in much of the developing world these gases- legal ones and even more dangerous illegal gases- are simply vented to the atmosphere when the cooling units are dumped or recycled.

In the first of ten more programmes highlighting the world's best carbon-busting ideas, Tom Heap meets the fridge detectives hunting the planet for the worst offenders and safely disposing of their dangerous gases.

Dr Tamsin Edwards of King's College, London, armed with statistics gathered by the Royal Geographical Society, joins Tom to add up the numbers and calculate the carbon impact of the fridge detectives.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in conjunction with the Royal Geographical Society. Particular thanks for this episode to Dr Luke Western and Dr Daniel Say of the University of Bristol and to Professor John Pyle of the University of Cambridge.

Some food crops convert just one percent of the sun's energy into edible food. If we can improve the process of photosynthesis we can grow more food on less land. Tom Heap visits a Yorkshire greenhouse to meet the team from Glaia with a cunning idea to do just that. Back in the studio, Dr Tamsin Edwards, climate scientist and fellow of the Royal Geographical Society, considers the potential impact on our global carbon emissions.

Producer: Alasdair Cross

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Vincent Gauci from the University of Birmingham.

Campaign and protest have been the traditional tools of environmental action in the UK. American lawyer, James Thornton, set up Client Earth to defend the planet in a different way- by using the courts. Using local laws to challenge governments and businesses they've had success across Europe and beyond, preventing the construction of coal-fired power stations and challenging the curse of air pollution. As well as enforcing environmental laws they're helping get new laws written.

Tom Heap meets James and discusses the carbon implications of his ideas with climate scientist, Dr Tamsin Edwards.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Pavlos Eleftheriadis from the University of Oxford and Professor Stephen Peake from the Open University.

Photo of James Thornton by Dan Wilton.

Trees are often thought to be the good guys when it comes to climate change. In Siberia, however, it's not always the case. The landscape was changed when humans arrived and the forest that took over from grasslands is causing problems. In Pleistocene Park, Russian scientists are carrying out a radical rewilding - removing trees and reintroducing species of grazing animals to help protect the permafrost - the deep frozen ground - from thawing and releasing methane into the atmosphere. Tom Heap and Dr Tamsin Edwards consider how this ambitious idea could help in the fight against climate change.

Producer : Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Vincent Gauci from the University of Birmingham.

Electricity from the sun is cheap and clean but the solar cells we see on our rooftops could be much more efficient. Henry Snaith of Oxford PV has developed a new material which helps solar roof panels extract more energy from the solar spectrum. Tom Heap visits Henry's lab and joins Dr Tamsin Edwards to consider the carbon-cutting potential of a new generation of solar energy.

Producer: Alasdair Cross

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Stephen Peake from the Open University.

Chilled lorries are the backbone of our food distribution system, keeping our pork pies and hummus safe and fresh on route to the supermarket. The problem for our air quality and carbon emissions is that many of the refrigeration units are powered by diesel engines.

Tom Heap meets a team converting these Transport Refrigeration Units from diesel to liquid nitrogen. If successful they could take a bite out of greenhouse gases in the west and, more importantly, offer a clean chilling option for farmers and food companies in the developing world. Food that spoils on the way to the consumer hurts farmers, causes hunger and increases carbon emissions. If meat, dairy, fruit and vegetables can be kept fresh for longer then everyone wins.

Dr Tamsin Edwards of King's College, London helps Tom calculate just how much carbon dioxide could be removed from the environment if we use techniques like this to slash food waste.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Harry Kennard from University College London.

The UK government is betting big on offshore wind to provide a huge percentage of our electricity by 2030. The turbines are certainly efficient, low carbon energy producers but they have one Achilles heel. They're expensive to maintain and repair. Boats or helicopters have to be sent out with a maintenance crew- it's dangerous and costly work. Developers in robotics and artificial intelligence have got together to come up with a solution. If an offshore turbine needs checking an unmanned boat will head out to sea. Once in position it will launch a drone which can inspect the turbine. If a closer look is needed then the drone can launch its secret weapon- the BladeBUG. It's a suitcase-sized robot which can cling to the huge turbine blades, check them and even clean or repair them. They should make new offshore wind development cheaper and safer.

Tom Heap meets the experts behind the robots - BladeBUG CEO Chris Cieslak; Professor Sara Bernardini from Royal Holloway, University of London - and works out the carbon impact of offshore wind expansion with climate scientist, 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 Professor Stephen Peake from the Open University and Rob Maynard from Ocean Resource Engineers Ltd.

Around the world many girls leave school before completing their education. It's said that those who stay to the end of high school have more agency and choice, but also earn more money and have fewer and healthier children.

Tom Heap hears how education and access to family planning don't just impact family size, they can also propel young women into positions of leadership where they can help their communities adjust to climate change.

Dr Tamsin Edwards of King's College, London helps Tom calculate just how useful secondary education for girls can be in the fight against climate change.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Mark Maslin from University College London and David Johnson of the Margaret Pyke Trust.

Simple and sublime seagrass meadows work naturally to absorb carbon. The leaves cause friction in the water and trap carbon from organic matter in the sediment. Yet industrial activity and pollution has damaged and reduced the extent of the meadows around the UK coast. With the marine environment improving, work is being done to restore patchy seabeds and create new ones, both in the UK and around the world. Take a dip with Tom Heap as he explores the wonders and potential of these plants on the sea floor.

Back in the studio Dr Tamsin Edwards of King's College, London helps Tom calculate just how useful seagrass can be in the fight against climate change.

Producer: Anne-Marie Bullock

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Vincent Gauci from the University of Birmingham.

BBC Radio Four presents 39 ideas to relieve the stress that climate change is exerting on the planet.

Trees soak up carbon dioxide, trees store carbon dioxide. So why not build with wood instead of concrete and steel? The usual reason is strength, but Dr Michael Ramage at Cambridge University has what he thinks is the answer- cross-laminated timber. It's strong enough to build a skyscraper and replaces lots of that carbon from conventional building. Tom Heap and Dr Tamsin Edwards take a look at the global possibilities of cities built of wood.

Producer : Alasdair Cross

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Dr Harry Kennard from University College London.

We?re resourceful, adaptable and the smartest thing this planet has ever seen. We got ourselves into this mess but we can get ourselves out of it. BBC Radio Four, in partnership with the Royal Geographical Society presents 39 ideas to relieve the stress that climate change is exerting on the planet.

From tiny solar cells to the total transformation of the Siberian landscape, Tom Heap and Dr Tamsin Edwards from Kings College, London view the fundamental problem of our age from a fresh perspective. Small things that make a big difference. Big things that make a small difference. We?re going to need every one of them.

In the first programme Tom discovers the secret of low-carbon rice with Dr Smita Kurup from Rothamsted Research.

Producer : Alasdair Cross

Researcher: Sarah Goodman

Produced in association with the Royal Geographical Society. Special thanks for this episode to Professor Vincent Gauci from the University of Birmingham.

Beating climate change takes the best ideas from the smartest minds.

In each 15 minute episode Tom Heap meets the people behind a fascinating idea to cut the carbon.