This paper presents a modeling study for evaluating the tidal energy extraction and its potential impacts on the marine environment in a real world site – Tacoma Narrows of Puget Sound, Washington State, USA. An unstructured-grid coastal ocean model, fitted with a module that simulates tidal energy devices, was applied to simulate the tidal energy extracted by different turbine array configurations and the potential effects of the extraction at local and system-wide scales in Tacoma Narrows and South Puget Sound.
Tacoma Narrows, WA, USA
- To simulate tidal energy extraction by tidal turbine farms in Tacoma Narrows, located in the southern portion of Puget Sound, in the State of Washington, USA.
- To evaluate the potential effects of tidal energy extraction on the physical environment.
Model results demonstrated the advantage of an unstructured-grid model for simulating the far-field effects of tidal energy extraction in a large model domain, as well as assessing the near-field effect using a fine grid resolution near the tidal turbines. The outcome shows that a realistic near-term deployment scenario extracts a very small fraction of the total tidal energy in the system and that system wide environmental effects are not likely; however, there are near-field effects on the flow field and bed shear stress in the area of tidal turbine farm. Model results also indicate that from a practical standpoint, hydrodynamic or water quality effects are not likely to be the limiting factor for development of large commercial-scale tidal farms. Results indicate that very high numbers of turbines are required to significantly alter the tidal system; limitations on marine space or other environmental concerns are likely to be reached before reaching these deployment levels. These findings show that important information obtained from numerical modeling can be used to inform regulatory and policy processes for tidal energy development.
Yang, Z.; Wang, T.; Copping, A.; Geerlofs, S. (2014). Modeling of In-Stream Tidal Energy Development and its Potential Effects in Tacoma Narrows Washington USA. Ocean & Coastal Management, 99, 52-62.