My research focus on several aspects of marine renewable energy development, with an emphasis on tidal current energy. Three examples are given here. The first is characterizing tidal energy resources over temporal and spatial scales spanning several decades of measurements. Methodologies are developed for data collection and analysis that inform structural design of tidal turbines and power generation estimates. The second is the identification and mitigation of environmental impacts associated with marine renewable energy generation. Areas of particular interest include underwater sound and direct interactions between marine animals and marine energy converters. The third is the development of hydrokinetic turbines at the micro-scale (i.e., peak capacity of 100 W) to provide power for autonomous oceanographic instrumentation. This research also affords the opportunity to study a number of engineering challenges for utility-scale (i.e., peak capacity of over 1 MW) systems, including control algorithms to maximize power production.