Treat light as a liquid

Set in an abandoned trolley terminal in the New York City subway, the high-tech Delancey Underground could be the world's first underground park. The Delancey Underground is an initiative to build the first underground park in an abandoned trolley terminal in the New York City subway system. In this episode of Futurestructures, we meet Dan Barasch, social director and co-founder of the project, and his co-founder James Ramsey, a former NASA engineer, who has devised the technology that uses bowl-like collectors and fiber optic wire to funnel sunlight from the street above, bathing the park in natural daylight and allowing enough light for plants to thrive.