Renewable Energy from the Tides: Research Update
The nation’s first commercial tidal power project began generating electricity from underwater turbines in Maine’s Cobscook Bay in September 2012. An SSI team led by Teresa Johnson, UMaine assistant professor of marine policy, and Gayle Zydlewski, UMaine research associate professor, is working with three stakeholder groups—tidal power developers, state and federal regulatory agencies, and local community members —to inform the sustainable development of this new technology. Recent progress includes:
- Identifying information needs and communication strategies. Stakeholders from fishermen to regulatory agencies need more information on how tidal turbines could affect fish and other marine life in Cobscook Bay, according to recent research by Johnson and team members Jessica Jansujwicz, SSI post-doctoral research fellow, and Chris Bartlett, marine extension associate with Maine Sea Grant and Cooperative Extension.
Johnson and her colleagues have developed effective communication strategies in response to these needs, which they identified through interviews, focus groups, and meetings. In collaboration with Zydlewski and the biological research team, they have held several community meetings to share research findings and gather input from fishermen and other community members to improve the social science and biological research.
- New fish survey reveals diverse species and seasonal patterns. In follow-up to Johnson’s findings, Zydlewski and School of Marine Sciences graduate student Jeffrey Vieser are conducting baseline surveys of fish populations in Cobscook Bay. The researchers collaborated with local fishermen to identify six sites of interest for sampling. In 2011, the researchers captured 32 fish species in the bay. This ongoing survey will yield new information about fish distribution in Cobscook Bay. Researchers will share findings with community members, developers, natural resource regulators, and other stakeholders to help inform decisions about tidal power development in the region.
- Understanding how fish interact with tidal turbines. Many fish use tidal currents to travel long distances during different life stages, and could be affected by the placement of tidal turbines. Haley Viehman, team collaborator and PhD student in the UMaine School of Marine Sciences, is monitoring fish interactions with a pilot tidal turbine in Cobscook Bay using stationary hydroacoustics.
As part of the Fish Assessment Study Team (FAST), Viehman is using a hydroacoustic beam to monitor the space immediately in front of the turbine for fish responses. In a preliminary study of a test device, Viehman found that fish were present around the turbine most of the time, and most often at night during slack tides. Also, more fish avoided the turbine during the day and larger fish were more likely to avoid the turbine, while smaller fish typically passed through it. This ongoing research, which is conducted in collaboration with energy developer Ocean Renewable Power Company (ORPC) and funded by Maine Sea Grant, will shed light on the potential impacts of tidal turbines on fish populations.
- Forging a new partnership with Japanese researchers. The Maine Tidal Power Initiative signed a research agreement with the North Japan Research Institute for Sustainable Energy of Hirosaki University in spring, 2012. The groups aim to foster scientific cooperation and academic exchange between the two universities to advance the development of sustainable tidal energy in both the U.S. and Japan.
Over the next year, the SSI team and collaborators will expand their research in several areas to help inform decision-making about tidal power development in Cobscook Bay and other sites in Maine. UMaine physical oceanographer Huijie Xue is characterizing the energy resource of Cobscook Bay, which will help determine where future turbines should be placed and how they will affect tidal currents. Xue and Zydlewski are also working collaboratively to examine how fish respond to different hydraulic conditions associated with the presence of a turbine.
Johnson and Jansujwicz will survey a larger population of residents in Eastport, Lubec, and other communities around the bay to gain deeper insight into public opinion about the social acceptability of tidal power in the region. The SSI team will continue to share findings with a diversity of stakeholders to help inform decisions about the sustainable development of tidal power in Cobscook Bay.
Ultimately, the team’s findings will help guide decision-making for stakeholders including regulatory agencies, communities investigating the potential of this technology at various scales, and ORPC, which is developing tidal power in Eastport.
Supported by National Science Foundation award EPS-0904155 to Maine EPSCoR at the University of Maine.