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Site Assessment and OptimizationWhile historical data exists on tides, waves and currents of the oceans and coastlines of the world, little of the work has been undertaken specifically to meet the detailed site-specific data needs of marine renewable energy development in eastern US coastal waters or nationally. Recently, as highlighted in April, 2008 during the Global Marine Renewable Energy Conference held in New York City, there is a growing realization of the need to undertake an intense exploration to support marine renewable energy siting and development. Very few coastal regions have had their hydrokinetic energy potential determined at the level required for site selection and technology deployment. As a result, technology companies are hindered in developing demonstration projects and commercial scale energy production enterprises. The problem is compounded by the need for niche expertise in ocean physics, biology, chemistry and ecology required to find the best energy generation sites for deployment and for producing the assessments and scientific evaluation required for permitting. In this context, Coastal Systems Program scientists within the University of Massachusetts-Dartmouth, School for Marine Science and Technology have been undertaking in a collaborative manner in-depth (site specific) oceanographic and environmental surveying in support of marine renewable energy development using tidal currents. The CSP effort is based upon experience with technology developers, demonstration projects and commercial ventures in Maine and Massachusetts over the past several years. This work has indicated that a significant "choke point" in the advance of marine hydrokinetic energy projects is the availability of accurate site characterizations based on quantitative physical data. Selected projects: An initial hydro-survey was conducted on September 27-28, 2007 by a Technical Team comprised of scientists from the Coastal Systems Group located in the University of Massachusetts-Dartmouth, School of Marine Science and Technology and a coastal processes engineer from Applied Coastal Research and Engineering, Inc. The purpose of the survey was to provide ORPC with hydrodynamic and physical data relative to their preferred location for deployment of their ocean power Turbine Generation Unit (TGU) in the southwestern corner of the Western Passage FERC site and to examine other regions of interest within the permit site, as appropriate. The actual data collected was:
At the request of ORPC, a second hydrodynamic survey was conducted in the Western Passage of Passamaquoddy Bay on November 4, 2007. This additional survey was to examine possible turbine testing locations inland of a line from Dog Island and Kendal Head, in the area north of the northern region of the ORPC FERC permit site. The hydro-survey was completed over both the flood and ebb tides on November 4, 2007 by scientists from the Coastal Systems Program (SMAST). In addition, a bathymetry survey was conducted at ~75 m intervals. The purpose of the survey was to determine if a suitable alternate location for testing of the TGU could be found and to provide the necessary bathymetric map to guide deployment. Additional, ADCP surveys were performed within the FERC site along transects situated in the northern portion of the FERC permit area and previously surveyed under spring tide conditions (September 27 and 28, 2007). These supplemental surveys conducted during neap tides were to enhance the data collected on the earlier surveys which were during spring tide in the lunar cycle. Having both neap and spring tide surveys would allow better forecasting of the flow field during future TGU deployments along transects within the FERC site. 
At the request of ORPC, an acoustic velocity meter was deployed in concert with environmental testing of the ORPC Turbine Generating Unit in order to cross compare turbine performance with the flow field acting as the driving force acting on the TGU. Instrumentation was deployed to capture an integrating measure of flow through the turbine unit. Along channel as well as cross channel and vertical flow was measured in addition to current velocities as a function of magnetic heading. Flow data was reconciled against tidal stage data and hydrodynamic surveys previously conducted for ORPC using ADCP in order gauge measured variations in velocities relative to lunar phase. 
The overall scope of this project was performed as a collaborative effort between the Ocean Renewable Power Company and the SMAST/Coastal Systems Program. In support of the deployment of the OCgen system in Cobscook Bay and Western Passage, a detailed survey of current and flow in the vicinity of two potential Cobscook Bay deployment areas was undertaken as specified by ORPC. Supplementary surveying in the northern portion of the ORPC FERC permit area in Western Passage was also be undertaken. Current velocities were measured using Acoustic Doppler Current Profiling (ADCP) technology over complete tidal cycles yielding a numeric and graphical characterization of the current thereby allowing for future optimal placement of the OCgen system in the water column. A total of eight transects in Cobscook Bay (six primary transects in proposed deployment areas and two secondary transects in the middle portion of the FERC permit area) as well as surveying of three supplemental transects in the northern portion of the FERC permit area in Western Passage surveyed for the purpose of the overall data collection effort. Measurements of tidal stage (TDR deployment completed from a pre-determined pier location) was also conducted in concert with current profiling in order to elucidate the variation of current intensity over the ebb/flood cycle of a tidal period. Profiling of currents and measurement of tidal stage was undertaken under near spring tide (lunar maximum) conditions to capture the maximum velocities of the current in the study area. 
The University of Massachusetts-Dartmouth, specifically the Advanced Technology Manufacturing Center (ATMC) and the SMAST-Coastal Systems Program have conducted research in Muskeget Channel, Massachusetts to determine the potential for future development of ocean renewable energy. A baseline survey (physical and biological) was undertaken of the Muskeget Channel area in Nantucket Sound and the greater region between Muskeget Island and Martha’s Vineyard. This initial baseline survey served as the technical basis for the Town of Edgartown to move forward with the planning of a tidal energy pilot program under its existing FERC permit. Assessment of environmental and biological conditions in Muskeget channel and nearby waters was also undertaken for areas to be considered as “test bed” for marine renewable energy projects (wind, wave, tidal). Data collection, synthesis and assessment focused on several components (determined as appropriate for a specific technology or sub-site) including tidal stage measurement, current velocities and flow volumes via Acoustic Doppler Current Profiling (ADCP) through lunar/tidal cycles and water column structure (Conductance, Temperature, Depth (CTD). Biological field data collection for habitat assessment included dissolved oxygen (high frequency measurements in targeted areas), macrophyte surveys (eelgrass & macroalgae) with incorporation of historical data, benthic infauna community characterization, survey of bottom sediments (sediment type, composition), survey of biota (planktonic, demersal, pelagic, benthic) based on historical research. 
The overall scope of this project was performed as a collaborative effort between the Passamaquoddy Tribe (Pleasant Point Reservation), Maine, Subsea Energy North America and the SMAST/Coastal Systems Program. In support of the tidal energy pilot project being conceived for the Western Passage in the vicinity of First Island and Kendall Head and to meet the criteria in the Preliminary Permit issued by the Federal Energy Regulatory Commission (FERC Project No. P-12710-002) to the Passamaquoddy Tribe, a detailed survey of the current velocity field at strategic hydrographic points within the First Island FERC permit area was conducted. Simultaneously, CSP scientists completed rudimentary bathymetry surveying as well as tidal stage measurements. Scientists within the Coastal Systems Program at the University of Massachusetts-Dartmouth, School for Marine Science and Technology (SMAST) were tasked with all data collection and synthesis in support of this initial oceanographic survey of the First Island FERC Permit Area and preliminary current profiles for the Kendall Head FERC Permit Area contained within the Western Passage north of Eastport, ME. Current velocities were measured along specific transect lines using Acoustic Doppler Current Profiling (ADCP) technology yielding a numeric and graphical characterization of the current. The initial survey enabled project developers to focus pilot project efforts on the most promising area within the First Island FERC permit domain and characterized the initial viability of the Kendall Head Site. 
Element 1 - Time-series current and wave field within the Muskeget Channel FERC Per mit Area and initial studies in the NORIEZ (including wind potential). Time-series current and wave data are being collected within both the Muskeget Channel FERC permit area and within the proposed NOREIZ being developed by the University of Massachusetts-Dartmouth Marine Renewable Energy Center (MREC). The Muskeget Channel deployments are being based upon field current profiling surveys to identify areas of optimum current fields for deployment of hydrokinetic technologies. The surveys are used to gain the spatial data on high velocity areas necessary to identify "hot spots" for potential energy production, that then have time series current profiling of currents over complete lunar cycles. The time-series work focuses on gaining the information necessary to support quantitative evaluation of potential energy production, specific engineering planning and design and permitting efforts, associated with identification of specific sites for technology deployment. In addition to quantifying the velocity field, the time-series data collection includes measurements of wave heights and frequency. These data are being collected both within the FERC permit area and in the NOREIZ. The study also includes initial data gathering on wind profiles for evaluation of wind energy potential associated with the NOREIZ. In concert with the field surveys within the NOREIZ is mapping of surficial sediments. Sediment characteristics and sediment transport are critical to understanding the physics of water movement and particularly the potential for structures to influence sediment transport (e.g. deposition, erosion, scour). As such, past data collection in Muskeget Channel is being extended southward into the NOREIZ to characterize surficial sediment types in a variety of locations that maybe supportive of future offshore wind development. Sub-bottom profiling is being conducted, as needed for future consideration of wind tower design, should there be a suitable wind resource south of the islands. Furthermore, determination of the composition of the sediment in specific areas is being undertaken as would be applicable for testing of future wind technologies. Assessment of the sediment characteristics of the sea bed aims to not only elucidate the engineering challenges associated with mooring or construction of energy devices but also to clarify the degree to which benthic animal communities may be affected by shifts in sediment transport. Element 2 – Town of Edgartown, Massachusetts FERC Permit Perimeter Area Investigation to Support Power Transmission to Upland Grid. While associated work is underway to determine the most feasible and economic paths for installing power cable from the grid to the shore, additional investigation is underway that focuses on assessing environmentally protected areas or areas requiring special permits that stand between the on-shore cable route and the high potential hydrokinetic energy generation sites within the Muskeget Channel FERC permit area. The work entails both upland nearshore evaluation of wetlands, dunes, etc that will need to be included in planning/implementation. Similarly, assessment of eelgrass beds and assessment of benthic infaunal animal communities and sediments along offshore cable routes is being determined. To answer questions related to power transmission via cables from an offshore array of tidal generating units and the effect on benthic environments two (2) cable routes being considered by the Town of Edgartown to bring power to shore are being investigated. For this portion of the study, CSP scientists are initially focusing on three specific environmental components as the engineering and permitting activities to support the burial of cables will require information that currently does not exist for the Muskeget Channel site (a) evaluation of the submarine biotic resources to be impacted during construction, primarily benthic infaunal communities and eelgrass beds. 
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