Marine energy—a collection of diverse technologies designed to capture energy from the ocean in various ways—has languished far behind more mature renewable technologies like wind, solar, and geothermal energy for decades. The reasons for its slow progress are as diverse as the technologies themselves, but there are some indications that a few of these technologies have learned from the failures of the past, and are finally becoming mature enough to reach commercial scale. Should they succeed in doing so, they offer the tantalizing potential to provide virtually limitless amounts of clean power, 24x7, using a wide variety of applications—from power supplied by cable to onshore grids, desalination of fresh water, standalone devices operating out in the deep ocean, devices that can convert the electricity they generate into synthetic liquid fuels for transportation by ship, and carbon capture technologies. But if we are to use the marine environment sustainably, we have to do so informed by solid scientific research into the impact our technologies will have on the marine environment and its wildlife residents. Our guest in this episode is one such researcher. An oceanographer by training, with deep expertise in the environmental effects of wave and tidal energy and offshore wind installations, Dr. Andrea Copping leads a team at the Pacific Northwest National Lab (PNNL) in Richland, Washington which integrates laboratory, field, and modeling studies into a coherent body of evidence to support siting and consenting decisions. She also leads OES-Environmental, an international project on environmental effects of marine energy development around the world, under the auspices of IEA Ocean Energy Systems. Join us in this wide-ranging discussion about the many different forms of marine energy, and how some of them might yet emerge as major players in the portfolio of energy transition solutions.