Nothing can stop solar's growth trajectory -- except maybe solar itself.This week, we have a deep discussion on the future of solar photovoltaics. Solar is exploding around the world, but have we grappled with the technology and market limitations that could stop the next order of magnitude in growth for PV?On this week's episode of The Interchange, Shayle Kann sits down with Varun Sivaram, author of the new book, Taming the Sun: Innovations to Harness Solar Energy and Power the Planet.Shayle and Varun examine every angle of the solar transition. They consider numerous possible futures, good and bad, for the technology. "If we do not take the right actions and urgently in innovation today, I warn that in the medium term we might run into a penetration ceiling for solar. And by the time that happens, it might have been too late to start investing in these long-term innovations that only pay off after you've invested for a little while," explains Varun.Varun Sivaram is the Philip D. Reed Fellow for Science and Technology at the Council on Foreign Relations, and an adjunct professor at Georgetown University.This podcast is brought to you by Fiveworx, a turnkey customer engagement platform for utilities. Find out more about how Fiveworx can help your customer engagement program succeed -- and get you beyond the meter.Subscribe to The Interchange podcast via Apple Podcasts, Google Play, Stitcher or wherever you find your audio content.