Sustainable energy in the form of natural gas, renewable energy and energy efficiency, is gaining ground in the U.S. and around the world, as concerns over climate change increase. And sustainable energy isn’t just cleaner, it’s cheaper, as well, as Ethan Zindler, the head of policy analysis at Bloomberg New Energy Finance, tells host Bill Loveless in this episode of the “Columbia Energy Exchange.” Their conversation took place just after BNEF and the Business Council for Sustainability released their 2017 Sustainable Energy in America Factbook.