We will discuss the science, technology, and policy issues of marine-, wave-, current-, and tidal-energy conversion as renewable energy resources. Studies on environmental effects of marine hydrokinetic energy devices (e.g., acoustic and electromagnetic influences on aquatic and benthic species, altered hydrodynamics, water quality, and sediment transport, or changes to currents, wave regimes, and tidal ranges), ocean thermal energy conversion, environmental monitoring, device-performance evaluation, resource assessment, grid integration, characterization of potential energy, forecasting across multiple time scales, impacts of energy extraction, system planning, risk assessment, and uncertainty are all of interest. Studies in riverine environments are also appropriate. The field of renewable energy is growing rapidly and multi-disciplinary approaches are welcomed and encouraged. International and early career researchers are particularly invited to submit. This session is coordinated with the other two sessions on Renewable Energy: Wind and Solar.