OES-Environmental distributes metadata forms (questionnaires) to solicit information from developers involved in environmental monitoring around marine renewable energy project sites around the world. This page provides project descriptions, baseline assessment, post-installation monitoring, and links to available data and reports. Content is updated on an annual basis.

Cobscook Bay Tidal Energy Project

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Description

The Cobscook Bay Tidal Energy Project was created to develop ORPC’s field operational and design experience in a feasible tidal flow environment, while providing renewable energy to the local grid, supporting community energy independence and resiliency. ORPC designed the TidGen® Power System deployed in the first phase of the project to operate in water depths of 60 to 150 ft. The core component of the TidGen Power System is ORPC’s proprietary turbine generator unit (TGU). The TGU utilized four advanced design cross-flow (ADCF) turbines to drive a permanent magnet generator mounted between the turbines on a common driveshaft. The TGU was 98 ft in length, 17 ft high and 17 ft wide. It was attached to a bottom support frame, which held the TGU in place approximately 15 ft above the sea floor. The bottom support frame was 98 ft long by 50 ft wide by 15 ft high. The bottom support frame was constructed of steel, and the TGU was constructed of steel and composite material. The coupled TGU and bottom support frame comprised the TidGen device. The TidGen device was connected to an underwater power consolidation module, which was then connected to an on-shore station through a single underwater power and data cable. The on-shore station was interconnected to the local power grid. The TidGen device and the related cabling and on-shore station comprised a complete TidGen Power System.

ORPC also designed and tested an OCGen® Module Mooring Project system at the Cobscook Bay Tidal Energy Site in 2014. The prototype OCGen device consisted of a buoyancy pod attached to a chassis with two turbines placed in the water column 35 feet below mean low water. It had no generator and was not grid connected. The turbines were re-used from a previous turbine model. The device was secured using gravity anchors and a tension-leg mooring system. 

ORPC’s Advanced TidGen Power System, partially funded by the US DOE, is a second generation technology, developed from operational experience both in Cobscook Bay, Maine and Igiugig, Alaska. The proposed system is based on a significant design effort performed in 2016 and design improvements generated through ORPC’s OCGen and RivGen projects. It will utilize a buoyant-tension mooring system similar to the OCGen rather than a bottom support frame utilized in the first generation TidGen. It will also transition from gravity anchors to a rock pin anchoring system.

Device/Array Installation Date: 
TidGen: September 13, 2012
OCGen Module: June 27, 2014 
ATGU: 2020
Advanced TidGen Mooring System: 2021
Advanced TidGen: 2022

Device/Array Removal Date: 
TidGen: July 15, 2013
OCGen Module: September 17, 2014
 

Location

The power system is located in Cobscook Bay on State of Maine submerged lands, near Eastport and Lubec, Maine, United States (44.9098°, -67.04563°).

Licensing Information

ORPC received a pilot project license for the Cobscook Bay Tidal Energy Project (Project) from the Federal Energy Regulatory Commission (FERC) on February 27, 2012 (FERC Project No. P-12711-005). ORPC obtained a preliminary permit for the Project area in Cobscook Bay from FERC on July 23, 2007; FERC issued a successive preliminary permit on January 13, 2011. Feasibility studies, including environmental surveys, and pre-filing consultation were conducted, resulting in ORPC’s filing of a draft pilot project license application with FERC on July 24, 2009 and subsequently, the final pilot project license application in September 2011.

On June 5, 2015, ORPC filed a request with the Commission to extend its license term for the Cobscook Bay Tidal Energy Project from eight years to ten years. This extended the expiration date from 2020 to 2022. However, in a March 14, 2017 submittal to FERC, ORPC stated that it did not intend to file a NOI or PAD for the Project at the time.

Project Progress

In March 2012, ORPC began construction of the Project off the coast of Eastport and Lubec, Maine (Figure 1). Following installation of the initial phase of the Project during the spring and summer of 2012, the Project began delivered electricity to the Emera Maine grid in September 2012 to July 2013. This was the first grid-connected installation of ORPC’s TidGen Power System.

A single-device TidGen Power System with a rated capacity of 150 kW was secured to a bottom support frame, which was fully installed with piles driven on April 8, 2012. The TGU was deployed on August 14, 2012. Subsea power and data cables were deployed on the seafloor and connected to the TidGen device. Electricity generated by the TidGen Power System was delivered by an underwater power cable to an On-shore Station in Lubec, Maine, where it was power-conditioned and connected to the Bangor Hydro Electric Company (now Versant Power) utility grid on September 13, 2012. ORPC entered into a 20-year agreement with Bangor Hydro Electric Company on January 1, 2013 for up to 5 megawatts at a price of $215/MWh, escalating at 2.0% per year.

Several issues occurred during construction and operation of the TidGen TGU which necessitated changes to the planned methodology. Retrievals of the TGU were required at more frequent intervals than planned. The significant cost increases incurred during operation and repair of the initial unit necessitated a reduction in number of additional units to be installed. In addition, the sooner than expected retrieval of the TGU and extensive repairs needed for the generator and EC caused a significant loss of operating time. The unit was in operation for a total of 734 hours during the Project. Electrical issues with the TGU electrical brake occurred upon reinstallation of the TGU. The unit was retrieved, repairs made, and then reinstalled on February 22, 2013. The Project assumed that the second retrieval would occur after six months of operation. The TGU retrieval was successfully conducted in the presence of DOE HQ staff on July 15, 2013. The TGU was transported to shore, placed on blocking and lifted onto a trailer for transfer to the concrete blocking pads on July 16, 2013. 

The status of the TidGen TGU led ORPC to consult with FERC and the Project’s Adaptive Management Team to determine an appropriate level of environmental monitoring while the TGU was out of the water. This effort culminated with the issuance of a temporary variance from environmental monitoring from FERC on October 29, 2013. ORPC continued some opportunistic environmental monitoring at the Project site in 2014 despite the temporary variance. These activities were associated with the deployment of ORPC’s OCGen Module Mooring Project at the site. Environmental monitoring included review of dive video for benthic growth on subsea components (Section 3.0 of this report). In addition, ORPC and the University of Maine School of Marine Sciences (UMaine) continued fisheries and marine life interaction research at the site in 2014 and 2015 through a separate UMaine funding award from DOE. ORPC then requested a two-year temporary variance extension to environmental monitoring during their technology optimization phase from FERC on December 31, 2015. The request for the two-year extension to the temporary variance for environmental monitoring was granted by FERC on March 2, 2016.

The OCGen Module Mooring Project deployed at the site in 2014 was designed to demonstrate the feasibility of a floating tensioned mooring system operating in a reversing flow tidal environment which could expedite installation and improve water column siting. The Module Mooring Project was installed from June 27, 2014 to September 17, 2014 and generation turbines rotated from July 24 to August 10, 2014. A similar tensioned mooring system design will be utilized in the Advanced TidGen system.

U.S. Senators Susan Collins and Angus King announced on August 31, 2016 that Ocean Renewable Power Company (ORPC) would receive $5,350,000 through the Department of Energy (DOE) to enhance the performance of its tidal turbine system. ORPC was one of 10 organizations across the country to receive funding to support the development of a commercially viable marine and hydrokinetic industry. This contract was signed with DOE on January 3, 2017. The new Advanced TidGen system will be built, installed, operated, and performance benchmarked in ORPC’s permitted Cobscook Bay Tidal Energy Project site followed by Western Passage, and employ local contractors and services providers.

ORPC plans to test the Advanced TidGen anchoring system and single turbine in 2021 followed by the Advanced TidGen device in 2022.The Cobscook Bay Advanced TidGen Power System site will not be grid connected. While the Cobscook Bay site serves as an excellent testing area, ORPC considers the tidal current velocities at the Project site inadequate to justify pursuing a commercial license. In a March 14, 2017 submittal to FERC, ORPC stated that it did not intend to file a notice of intent (NOI) to relicense the project or a Pre-Application Document (PAD) at the time. ORPC anticipates that the project infrastructure in place, the environmental monitoring and data analysis efforts, resource information documentation, and collaborative relationships with existing marine users will continue through the duration of the existing pilot license term and beyond. 

Table 1. Federal and/or state listed threatened (T) and endangered (E) species with potential to occur in project area. 

Species

Federal Status

State Status

Shortnose Sturgeon (Acipenser brevirostrum)

E

E

Atlantic sturgeon (Gulf of Maine Distinct Population

Segment (DPS)) (Acipenser oxyrinchus)

T

N/A

Atlantic salmon (Gulf of Maine DPS) (Salmo salar)

E

N/A

Leatherback sea turtle (Dermochelys coriacea)

E

E

Loggerhead sea turtle (Caretta caretta)

T

E

Sei whale (Balaenoptera borealis)

E

E

Fin whale (Balaenoptera physalus)

E

E

North Atlantic right whale (Eubalaena glacialis)

E

E

Humpback whale (Megaptera novaeangliae)

E

E

ORPC designed and carried out the following monitoring plans to ascertain the Cobscook Bay Tidal Energy Project’s environmental effects:

  • Acoustic Monitoring
  • Benthic and Biofouling Monitoring
  • Fisheries and Marine Life Interaction Monitoring
  • Hydraulic Monitoring
  • Marine Mammal Monitoring 
  • Bird Monitoring 

In addition, as required by ORPC’s FERC License, an Adaptive Management Plan has been implemented that describes and manages the process for evaluating environmental monitoring data and license modifications where appropriate. The Adaptive Management Team is comprised of the jurisdictional federal and state agencies and ORPC.
 

Environmental Webpage: http://www.orpc.co/our-approach/environmental-affairs

Papers, Reports, Research Studies

Annual Environmental Monitoring Reports

Project Commercialization Technical Report

Other Reports and Papers

 

Baseline Assessment: Cobscook Bay Tidal Energy Project

Receptor Study Description Design and Methods Results Status
Marine Mammals Marine mammal presence and interactions. Incidental visual observations; testing of active acoustic monitoring (AAM) system. Visual observations recorded primarily harbor seals at the project site; AAM testing indicated positive results for detecting and tracking marine mammal sized targets. Completed
Fish Fisheries presence and turbine interactions. Hydroacoustic and trawl surveys of project and control sites; interaction studies around ORPC’s beta turbine. Hydroacoustic and trawls surveys combined to detail fisheries presence (seasonality, vertical distribution, diurnal patterns, etc.) and speciation. Interaction studies demonstrated fish behavior. Completed
Birds Species presence and behavior. Visual observations. Species presence, behavior, and seasonality documented. Completed
Invertebrates Benthic community survey. Benthic dive survey of deployment area and cable route. Species presence and distribution documented. Completed
Physical Environment Bathymetric mapping and sediment characterization. Detailed bathymetric mapping, side-scan sonar, sub-bottom profiling and magnetometer surveys. Data used to characterize the bottom and identify potential cultural resources and marine hazards. Preliminary results led ORPC to change deployment strategy of turbines in Cobscook Bay primarily due to thickness of unconsolidated sediments. Completed
Physical Environment Water velocity surveys.
Acoustic Doppler Current Profiler (ADCP) surveys. Hydraulic circulation modeling. ADCP surveys and hydraulic modeling contributed to the selection of turbine deployment locations. Completed
Physical Environment, Marine Mammals Underwater acoustic survey. Drifting Noise Measurement System (DNMS) at project site and around ORPC’s beta turbine. Beta turbine operation did not elevate underwater sound levels more than 10 dB above ambient levels and is not expected to cause harassment to marine mammals. Completed
Physical Environment The primary goals of the Acoustic Monitoring Plan were to identify and characterize the noise radiated by the TidGen® Power System in the high-velocity environment of the Project site by gathering acoustic data under various environmental and mechanical conditions prior to and during Project deployment.
 Measurements were collected at the project site using a drifting noise measurement system (DNMS). Measurements of the in-water noise level related to the TidGen® Power System demonstrate that sound levels in the vicinity do not exceed 120 dB re 1 µPa2/Hz at any frequency while the turbine is rotating, both while generating and when freewheeling.
 Completed

Post-Installation Monitoring: Cobscook Bay Tidal Energy Project

Stressor Receptor Study Description Design and Methods Results Status
Collision Marine Mammals The primary goal of the Marine Mammal Monitoring Plan is to identify the species, number of animals and their behavior to characterize changes in marine mammal use in and around the deployment area due to the presence of hydrokinetic devices. ORPC conducted visual observations of marine mammals in and around the Project area concurrently with other project-related tasks conducted in 2013. Marine mammal observations made by trained personnel in 2013, including during periods of operation, maintenance and retrieval did not indicate changes in marine mammal presence or behavior. There is no evidence of marine mammal strike with system components during deployment and retrieval or with TGU foils during operation. Completed
Habitat Change Invertebrates The primary goals of the Benthic and Biofouling Monitoring Plan are to evaluate the benthic community during the Project and to study whether the structures introduced into the marine system contribute to biofouling accumulation that may alter the habitat within the Deployment Area. ORPC deployed video transect lines and video recordings were made by scuba divers. Benthic sampling was conducted in situ by the divers along the transect. ORPC performed biofouling assessments. The TidGen® TGU was assessed for percent coverage of biofouling on distinct structural components, and biological samples were taken from representative locations. In 2014, the installation of the OCGen® Module Mooring Project at the Cobscook Bay Tidal Energy Project site provided an opportunity to inspect the TidGen® bottom support frame, shore cable termination anchor, and the Simrad tower for benthic growth. MER Associates review of ORPC’s November 9, 2013 benthic survey of the cable route concluded that exposed sections of the cable were causing minimal disturbance to the seabed and were not adversely impacting the surrounding habitat or benthic epifauna. In addition, the buried portion of the cable was stationary and was not expected to cause any disturbance impacts. Review of the dive video and visual inspection following retrievals of the TidGen® indicate minimal biofouling of the TidGen® device. The July 2014 observations were generally consistent with those previously recorded and confirmed a continued presence of benthic organisms on subsea structures.
 Completed
Attraction, Avoidance, Collision Fish, Marine Mammals The goal of the Fisheries and Marine Life Interaction Monitoring Plan was to collect pre-deployment and post-deployment information to provide an initial description of fish distribution and relative abundance within Cobscook Bay to supplement existing information for the general
Passamaquoddy Bay area.The Fisheries Monitoring Plan is a continuation of research started by UMaine researchers in 2009.
 The study was designed to capture tidal, seasonal and spatial variability in the presence of fish in the area of interest (near the TidGen® device deployment site). The design involved down-looking hydroacoustic surveys during several months of the year, and examined the vertical distribution and relative abundance of fish at the project and control site (for relative comparison). Pre-deployment data were collected in 2010, 2011, and early 2012, and post-deployment data were collected from August 2012 through September 2013. In 2015 UMaine’s Fish Assessment Study Team completed research related to marine life interaction data around the OCGen® Module deployed in 2014. In 2016 UMaine’s Fish Assessment Study Team continued processing, analyzing, and interpreting data collected at the Project site in 2012-2014.
 The hydroacoustic surveys indicated that there was a significant decline in fish density closer to the turbine beginning approximately 140 m from the free-spinning OCGen® prototype device. Noise and natural flow patterns appeared to be the most plausible explanations for the observed patterns in fish behaviour. The study provides additional confirmation that a single turbine is unlikely to result in
more than negligible impacts to fish communities.
 Completed
Attraction, Avoidance, Displacement Birds The primary goal of the Bird Monitoring Plan was to determine the species, number, and time of peak use of sea and shore birds in the Deployment Area, the onshore landing site where the underwater P&D cables of the TidGen® Power System comes ashore, and the waters immediately off the landing site. Post-deployment sea and shore bird monitoring was conducted by the Center for Ecological Research (CER) using trained observers familiar with local bird species and behavior. CER observed a decline in several species of seabirds in the Cobscook Bay study area in 2012- 2013, compared to the previous two winters. It seems unlikely that the operation of the TidGen® Power System affected seabird numbers. CER surveys did not find any federally or state endangered or threatened species. Completed
Changes in Flow Physical Environment, Sediment Transport The primary goal of the Hydraulic Monitoring Plan was to characterize the hydrological zone of influence, area for the Project.
 ORPC worked with Sandia National Laboratories (SNL) and Sea Engineering, Inc. to apply their SNL-EFDC Model to assess hydrodynamics at the Project site. TidGen® foundation piles were marked prior to installation for the purpose of measuring changes to seabed elevation from scour.
 Results of the scour monitoring indicate minimal change in seabed elevation around the foundation piles. Completed
Noise Fish, Marine Mammals In compliance with its Incidental Harassment Authorization, ORPC also conducted various environmental monitoring and mitigation procedures to limit and evaluate the impacts of pile driving activities between March 24 and April 4, 2012. Additional hydroacoustic monitoring continued after the removal of the TidGen. Acoustic monitoring during pile driving activities included in-air acoustic monitoring and hydroacoustic monitoring at various near and far field ranges. Marine mammal observations on vessels around the site and on land also occurred during installation. Acoustic monitoring continued post-installation. A final report on the acoustic, marine mammal and bird monitoring studies during Phase I pile driving activities was prepared for NOAA. Pile driving source levels were below regulatory thresholds. Completed
Noise Physical Environment The primary goals of the Acoustic Monitoring Plan were to identify and characterize the noise radiated by the TidGen Power System in the high-velocity environment of the Project site by gathering acoustic data under various environmental and mechanical conditions prior to and during Project deployment.

 Measurements were collected at the project site using a drifting noise measurement system (DNMS). Measurements of the in-water noise level related to the TidGen Power System demonstrated that sound levels in the vicinity did not exceed 120 dB re 1 µPa2
/Hz at any frequency while the TidGen turbine was rotating, both while generating and when freewheeling.
 Completed
Habitat Change Fish The goal of the Fisheries and Marine Life Interaction Monitoring Plan was to collect pre-deployment and post-deployment information to provide an initial description of fish distribution and relative abundance within Cobscook Bay to supplement existing information for the general Passamaquoddy Bay area. The Fisheries Monitoring Plan is a continuation of research started by UMaine researchers in 2009.
 The study was designed to capture tidal, seasonal and spatial variability in the presence of fish in the area of interest (near the TidGen device deployment site). The design involved down-looking and side-looking hydroacoustic surveys during several months of the year, and examined the vertical distribution and relative abundance of fish at the project and a control site in Cobscook Bay. Pre-deployment data were collected in 2010, 2011, and early 2012, and post-deployment data were collected from August 2012 through July 2015. In 2015 UMaine’s Fish Assessment Study Team completed research related to marine life interaction data around the OCGen Module deployed in 2014. In 2016 and 2017 UMaine’s Fish Assessment Study Team continued processing, analyzing, and interpreting data collected at the Project site in 2012-2015.

 Hydroacoustic data found variable fish densities and vertical distributions across diel and tidal cycles. The OCGen hydroacoustic surveys indicated that there was a significant decline in fish density closer to the turbine beginning approximately 140 m from the free-spinning OCGen prototype device. Noise and natural flow patterns appeared to be the most plausible explanations for the observed patterns in fish behaviour. Single devices spanning a small prorportion of a channel are not expected to generate avoidance behaviors that may significantly delay or reduce overall fish passage. Hydroacoustic studies provided additional confirmation that a single turbine is unlikely to result in more than negligible impacts to fish communities.
Completed
Habitat Change Birds The primary goal of the Bird Monitoring Plan was to determine the species, number, and time of peak use of sea and shore birds in the Deployment Area, the onshore landing site where the underwater P&D cables of the TidGen Power System comes ashore, and the waters immediately off the landing site. Post-deployment sea and shore bird monitoring was conducted by the Center for Ecological Research (CER) using trained observers familiar with local bird species and behavior. CER observed a decline in several species of seabirds in the Cobscook Bay study area in 2012- 2013, compared to the previous two winters. It seems unlikely that the operation of the TidGen Power System affected seabird numbers. CER surveys did not find any federally or state endangered or threatened species. In addition, no significant disturbance to seabirds were observed during installation activities. Completed