title: Marine Hydrokinetic Energy from Western Boundary Currents.
abstract: The kinetic energy in ocean currents, or marine hydrokinetic (MHK) energy, is a renewable energy resource that can help meet global energy requirements. An ocean circulation model-based census shows that subtropical surface western boundary currents (WBCs) are the only nearshore, large-scale currents swift enough to drive large electricity-generating ocean turbines envisioned for future use. We review several WBCs in the context of kinetic energy extraction. The power density in the Gulf Stream off North Carolina at times reaches several thousand watts per square meter at 75 m below the surface, and the annual average power is approximately 500-1,000 W m-2. Significant fluctuations occur with periods of 3-20 days (Gulf Stream meanders) and weeks to months (Gulf Stream path shifts). Interannual variations in annual average power occur because of year-to-year changes in these WBC motions. No large-scale turbines presently exist, and the road to establishing MHK facilities in WBCs will encounter challenges that are similar in many aspects to those associated with the development of offshore wind power.
authors: Department of Marine Sciences, University of North Carolina, Chapel Hill, North Carolina 27599-3300; email: bane@unc.edu , sarahaines@unc.edu.
authors: John M
authors: JM
authors: Bane
authors: Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695-8208; email: rhe@ncsu.edu , ygong3@ncsu.edu.
authors: Ruoying
authors: R
authors: He
authors: University of North Carolina Coastal Studies Institute, Wanchese, North Carolina 27891; email: muglia@csi.northcarolina.edu.
authors: Michael
authors: M
authors: Muglia
authors: Department of Marine Sciences, University of North Carolina, Chapel Hill, North Carolina 27599-3300; email: bane@unc.edu , sarahaines@unc.edu.
authors: Caroline F
authors: CF
authors: Lowcher
authors: Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695-8208; email: rhe@ncsu.edu , ygong3@ncsu.edu.
authors: Yanlin
authors: Y
authors: Gong
authors: Department of Marine Sciences, University of North Carolina, Chapel Hill, North Carolina 27599-3300; email: bane@unc.edu , sarahaines@unc.edu.
authors: Sara M
authors: SM
authors: Haines
mesh_terms: D003246:Conservation of Energy Resources; D004560:Electricity; D005544:Forecasting; D009792:Oceans and Seas; D014872:Water Movements; D014919:Wind
keywords: Cape Hatteras; Gulf Stream; alternative energy; ocean turbine; power density