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.