Reusing waste heat, The British Library’s solar project and India’s stepwells

What are some of the ways that heating the air and water in our buildings can be made greener? We consider innovative solutions from the capture and redistribution of a building’s warmth to a solar project in London that is decarbonising The British Library’s water-heating process. Plus: we visit one of India’s historic stepwells to see how the ancient structures could provide an answer to the country’s water-supply woes. See omnystudio.com/listener for privacy information.