In this final episode of the USEA Power Sector Podcast series on energy storage, Paul Jacob, CEO of Rye Development, answered questions by journalist Herman K. Trabish about how closed loop pumped storage hydropower, or PSH, fits into the broad spectrum of mechanical energy storage, the enormous capacity potential of PSH, where it is already in use, what its cost benefit economics are, and why closed loop technology solves some of conventional hydropower’s environmental concerns.