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Hypothetical power dissipation by a tidal in‐stream energy conversion device was calculated for Admiralty Inlet, Washington, a highly energetic entrance channel to Puget Sound and currently a candidate for tidal energy development. Power dissipation was calculated for a device of a given capacity as a function of hub height above sea bottom (z), using acoustic Doppler current profiler data taken in 2007 and 2009 at seven locations throughout the Inlet. At five of the seven locations, where the tidal currents were predominantly bi‐directional, power dissipation density increased roughly as ~zγ , with the exponent γ narrowly ranging from 0.62 to 0.66, up to at least z = 18m. At two of the five sites where the water depth exceeded this substantially, power was found to increase further with z but at slower rates with γ = 0.19 and 0.42. The remaining two sites out of the seven were both close to shoreline features, and the currents deviated significantly from bi‐directionality. At one of the two the power increased at a slower rate of γ = 0.35 – 0.5, while at the other the increase was faster with γ = 0.91 – 0.96. The increase in power with height at the bi‐directional sites is faster than would be expected from the one‐seventh power law applicable to turbulent channels. However, it is still slower than the likely increase in the cost of device foundation with height, which would at a minimum scale as ~z due to the cost of materials alone, and likely scale faster in order for the installation to withstand the overturning moment exerted by the tidal current. Thus, placing a tidal device high in the water column to exploit stronger currents may not be economically attractive, given that the device operator needs to recoup the higher cost of device foundation required.

Reference Model #1 is a tidal turbine operating in a narrow, tidal channel. The site is a generalized version of Tacoma Narrows, Puget Sound, Washington. The resource is a mixed, mainly semidiurnal tidal regime with two ebbs and floods each day of unequal strength (i.e., a diurnal inequality in which a strong ebb/flood exchange is followed by a weak exchange). The diurnal inequalities provide extended windows of weak currents for device installation and maintenance activities relative to a purely semidiurnal tidal regime, though at the expense of reduced generation potential for equivalent peak currents. In order to evaluate device performance, a generalized probability distribution and vertical profile for current speeds in a mixed, mainly semidiurnal tidal regime is required. Once the distribution of velocities is known, leading‐order device performance may be evaluated based on the device operating parameters at each point on the distribution. These parameters include cut‐in speed, rated speed, and power conversion efficiency.

Due to the strong presence of wind resources in the South Atlantic, the Carolinas have emerged as the new frontier in the development of offshore wind energy. The two states have moved in parallel, completing research and establishing committees to explore their offshore wind potential. This paper presents the opportunities and challenges for the Carolinas to collaborate in offshore wind energy planning. This is done using a three-­‐part approach. First, the paper reviews existing scientific literature to describe the case for interconnecting wind farms. Secondly, it analyzes the existing policy frameworks of the federal government and the two states. Lastly, it demonstrates the utility of marine spatial planning and ArcGIS in siting offshore wind farms, transmission lines and aiding in collaboration. This paper concludes that in order to move forward with stronger collaboration the Carolinas must streamline the policy realm, shift towards a regional perspective, increase marine spatial planning initiatives, develop economic incentives and further involve stakeholders. With respect to marine spatial planning, this study includes a sample GIS analysis that provides three transmission configurations for the Carolinas. These include i.) a backbone parallel to shore ii.) a backbone with onshore injection at Georgetown and North Myrtle Beach, SC and iii.) a radial configuration that considers Department of Defense exclusions.

Two independent methods are developed to assist in determining the optimum locations for siting offshore renewable energy facilities (winds). A spatial typology, based on multivariate statistical analysis, namely Principal Components and Cluster Analyses (PCCA), identifies homogeneous marine regions based on geophysical resources and development constraints. A Technology Development Index (TDI), defined as the ratio of technological challenges faced to extract energy versus power resources available is also introduced. Both methods are applied, within a marine spatial planning framework, to Rhode Island and Southeast New England coastal waters, to determine optimum sites offshore wind turbines supported by lattice jacket structures. The methods are robust to variance in the input data and give results in good agreement with each other. Copyright © 2010 by The International Society of Offshore and Polar Engineers (ISOPE).

Re-analyzed acoustic Doppler current profiler (ADCP) data originally collected by NOAA CO-OPS (Center for Operational Oceanographic Products and Services) and equivalent point data from Pacific Northwest National Laboratory's FVCOM (Finite Volume Community Ocean Model) model of the region. Data are processed to products describing characteristics of tidal currents relevant to tidal turbines, as well as power output estimates for a notional turbine deployed from a surface platform or from the seabed at each location. These data underpin the results presented in their associated paper - see below.

Data files for the NWEI Azura grid-connected deployment at the 30-meter berth of the US Navy's Wave Energy Test Site (WETS 30m Site) at the Kaneohe Marine Corps Base Hawai'i (MCBH) on the windward (northeast) coast of the island of Oahu, HI. See general documentation describing specifics of the data files and formats in a separate submission.

Data files for the NWEI Azura grid-connected deployment at the 30-meter berth of the US Navy's Wave Energy Test Site (WETS 30m Site) at the Kaneohe Marine Corps Base Hawai'i (MCBH) on the windward (northeast) coast of the island of O'ahu, HI. See general documentation describing specifics of the data files and formats in a separate submission.

Data files for the NWEI Azura grid-connected deployment at the 30-meter berth of the US Navy's Wave Energy Test Site (WETS 30m Site) at the Kaneohe Marine Corps Base Hawai'i (MCBH) on the windward (northeast) coast of the island of Oahu, HI. See general documentation describing specifics of the data files and formats in a separate submission.

Data files for the NWEI Azura grid-connected deployment at the 30-meter berth of the US Navys Wave Energy Test Site (WETS 30m Site) at the Kaneohe Marine Corps Base Hawaii (MCBH) on the windward (northeast) coast of the island of Oahu, HI. See general documentation describing specifics of the data files and formats in a separate submission.

Data files for the NWEI Azura grid-connected deployment at the 30-meter berth of the US Navys Wave Energy Test Site (WETS 30m Site) at the Kaneohe Marine Corps Base Hawaii (MCBH) on the windward (northeast) coast of the island of Oahu, HI. See general documentation describing specifics of the data files and formats in a separate submission. This month's data only covers the period Dec 1-6, 2016. On Dec 7, the Azura was shut down and disconnected in preparation for its Dec 8 removal from the WETS 30 m site. The Azura will be modified and re-deployed in 2017.