When you think of the future of clean energy, wind and solar might be the first things that come to mind. But when the wind doesn't blow and the sun doesn't shine, the need for alternative sources of power becomes apparent. From advanced geothermal to nuclear fusion, up-and-coming advancements may deliver a future of abundant, clean energy. One of the most ambitious ideas is space-based solar: orbiting solar panels that can beam energy to the Earth from space. Is this a viable energy solution ... or a sci-fi pipe dream? To find out more, I'm joined by Ali Hajimiri. Ali is the Bren Professor of Electrical Engineering and Medical Engineering at the California Institute of Technology, as well as Co-Director of the Space-Based Solar Power Project at Caltech.