Tidal hydrokinetic energy has the potential to provide clean, reliable power, and emerging turbine designs are making production of electricity from ocean energy technologically and economically feasible. Tidal energy projects could be a viable renewable energy source, displacing fossil fuel-based energy resources, providing benefits to the marine environment through the mitigation of carbon dioxide production (which can lead to ocean acidification and climate change) and a reduction in the risk of catastrophic spills associated with fossil fuel extraction and transportation. However, the risk to the marine environment and marine organisms from tidal energy generation is not well known.
In order to appropriately site and operate tidal power installations and explore the potential contribution tidal power can make to a renewable energy portfolio, the environmental risks of the technology must be better understood. In doing so, it is important to distinguish between environmental effects and environmental impacts. Environmental effects are the broad range of potential measurable interactions between tidal energy devices and the marine environment. Environmental impacts are effects that, with high certainty, rise to the level of deleterious ecological significance.
This report summarizes the outcomes of a March 22-25, 2010, workshop in Seattle, Washington, on the environmental effects of tidal energy development. The workshop focused on building capabilities to evaluate the environmental effects of tidal energy from turbines placed in the water column throughout the United States. However, it did not address policy issues, details of technology engineering, or the socioeconomic impacts of tidal energy development.