Month: August 2021

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.