The U.S. Navy’s Wave Energy Test Site (WETS), the United States’ first grid- connected wave energy test site, was expanded to three test berths in 2015. Through a cooperative effort between the Navy and the US Department of Energy (DOE), with the support of Hawai’i Natural Energy Institute and the Hawai’i National Marine Renewable Energy Center, WETS hosts companies seeking to test their pre-commercial WEC devices in an operational setting, enabling them to advance their device transition readiness level. Several devices have already been tested. HNEI provides performance analysis, numerical modeling of devices and moorings, wave measurement and forecasting, environmental monitoring (primarily acoustics), and logistics support to the Navy and the companies deploying at WETS.
The U.S. Navy Wave Energy Test Site is located north of Mōkapu Peninsula, Marine Corps Base Hawaii, Kaneohe Bay, O’ahu, Hawai’i.
An Environmental Assessment was required for permitting the deep water berths, at 60 and 80m water depths at WETS under the National Environmental Policy Act, and it was completed in 2014 with a finding of no significant impacts. An Environmental Impact Statement was not required. The berths at WETS are pre-permitted for testing of generic point absorbers and oscillating water column (OWC) devices. Developers must individually complete device-specific categorical exclusion applications, and an Army Corp of Engineers permit.
2003 – Environmental Assessment for shallow water Wave Energy Technology (WET) Project (30m shallow berth)
2004 – 2010 – PowerBuoy PB-40 deployment with periodic removal for maintenance and upgrades
Feb 2014 – Environmental Assessment completed for WETS (expanding the site to include berths at 60m and 80m depth)
May 2015 – Dec 2016 – NWEI 18kW Azura device deployed at 30m berth
Mar 2016 – Apr 2017 – Fred. Olsen Lifesaver device deployed at 60m berth
Feb – Aug 2018 – second deployment of Azura at 30m berth
Oct 2018 – Mar 2019 – redeployed Lifesaver at 30m
Planned – C-Power 2 kW SeaRay deployment
Planned – Oscilla Triton-C deployment at 30 m berth
Planned – Ocean Energy 500kW OE35 deployment at 60m berth
Key Environmental Issues
The environmental monitoring program at WETS was designed to include device acoustic signature measurement, device and power cable electromagnetic fields (EMFs), and possible changes in device/mooring-induced sediment transport, seawater chemistry, and the ecological environment. Sediment transport, seawater chemistry, and ecological environmental monitoring have been completed and protocols established. Following the general acceptance that EMF impacts are negligible for levels of power production at WETS, EMF monitoring was not conducted at WETS. Acoustic measurements became the focus of HINMREC and are now continuing under Navy funding, and have been expanded to include mooring infrastructure.
Papers, Reports, Research Studies
- Wave Energy Test Site Environmental Assessment: Marine Corps Base Hawaii (NAVFAC 2014)
- Characterization of U.S. Wave Energy Converter (WEC) Test Sites: A Catalogue of Met-Ocean Data
- Marine Ecological Assessment of Proposed Wave Energy Project Area Offshore Marine Corps Base Hawaii, October 2003 – May 2011
- Proposed Wave Energy Technology Project Environmental Assessment (Navy 2003)
- Biological Evaluation Effects of Bathymetric Surveys Required for Wave Energy Conversion Testing Facilities Planned for Kaneohe Bay and Pauwela (Maui)
- Kane‘ohe Wave Energy Test Site: Multibeam Bathymetry Survey (2011)
- Kane‘ohe Wave Energy Test Site: Sub-Bottom Profiler Survey (2011)
- Kane‘ohe Wave Energy Test Site: Remotely Operated Vehicle Survey(2012)
- Geophysical Surveys of the Wave Energy Test Site at MCBH, Kane‘ohe (2012)
- Geophysical Surveys of the Wave Energy Test Site at MCBH, Kane‘ohe: Diver Surveys Site 2 (2012)
- Kane‘ohe Wave Energy Test Site: Side Scan Data Report 2 (2013)
- Kane‘ohe Wave Energy Test Site: Dive Survey Report (2013)
- Wave Energy Resources for Representative Sites Around the Hawaiian Islands (2010)
- Wave Energy Test Site Progress Report: Comparison of Wave Hindcast Model Results with Waverider Measurements (2012)
- Wave Energy Resource Characterization at the U.S. Navy Wave Energy Test Site and Other Locations in Hawai‘i (2014)
- Annual Report of the Wave Energy Test Site at MCBH, Kane‘ohe (2017)
- WETS Acoustic Measurement Field Reports (2014-2017)
- WETS Shore Side Report: Acoustic Doppler Current Profiler (ADCP) Installation(2015)
- WETS Acoustic Survey Final Report (2019)
- WETS Acoustic Doppler Current Profiler (ADCP) Data Report (2012)
- WETS Comparison of Waverider Data & Sentinel V100 ADCP Data Reports (2015)
- WETS Sentinel V100 ADCP Data Analysis at 30m Reports
- WETS Sentinel V100 ADCP Data Analysis at 70m Reports
- WETS Deepwater Mooring Inspection (2017)
- Evaluation of WETS Mooring: Failure Mode Investigation Report (2017)
- Investigation of Wave Energy Converter Effects on Near-Shore Wave Fields: Model Generation, Validation and Evaluation – Kaneohe Bay, HI (2012)
- PacIOOS Wave Buoy 225: Kaneohe Bay WETS, Oahu, Hawaii.
- Persistent Environmental Monitoring Near an Operational Wave Energy Converter (2019)
- Numerical wave modeling for operational and survival analyses of wave energy converters at the US Navy Wave Energy Test Site in Hawaii
- Assessment of wave energy resources in Hawaii
Conference Proceedings & Presentations
2019, P. Cross, K. Rajagopalan, A. Druetzler, A. Argyros, J. Joslin, E. Hjetland, A. Stewart, Recent Developments at the U.S. Navy Wave Energy Test Site, Proceeding of the European Wave and Tidal Energy Conference, Naples, Italy, September 1-6.
2018, P. Cross, Ocean Testing at WETS – Ramping Up, Presented at the HydroVision Conference, Charlotte, North Carolina, June 28.
2018, P. Cross, U.S. Navy Wave Energy Test Site, Presented at the International Marine Renewable Energy Conference, Washington, DC, May 2.
2018, K. Rajagopalan, P. Cross, L. Vega, Numerical Modeling of the Lifesaver Mooring System for Deployment at WETS, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., April 30 – May 2.
2018, N. Li, K.F. Cheung, P. Cross, Probabilistic Distributions of Extreme Wave Heights at the Wave Energy Test Site, Hawaii, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., April 30 – May 2.
2018, P. Cross, Environmental Measurements at the U.S. Navy’s Wave Energy Test Site, Presented at the Environmental Interactions of Marine Renewables, Kirkwall, Orkney, Scotland, April 24.
2017, P. Cross, HNEI Role at U.S. Navy Wave Energy Test Site, Presented at the Ocean Renewable Energy Conference, Portland, Oregon, September 13-14.
2017, B. Polagye, P. Murphy, L. Vega, P. Cross, Acoustic Characteristics of the Lifesaver Wave Energy Converter, Presented at the European Wave and Tidal Energy Conference (EWTEC), Cork, Ireland, August 27 – September 1.
2017, T. Lettenmaier, B.A. Ling, L.A. Vega, E. Nelson, Open Ocean Testing of the Azura Prototype Wave Energy Converter in Hawaii, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., May 1-3.
2017, T. Lettenmaier, B. Ling, L. Vega, E. Nelson, Open Ocean Testing of the Azura Prototype Wave Energy Converter in Hawaii, Poster presented at the Marine Energy Technology Symposium (METS), Washington, D.C., May 1.
2017, N. Li, K.F. Cheung, P. Cross, L. Vega, Probabilistic Wave Parameters for WEC Survival Analysis at US Navy’s Wave Energy Test Site in Hawaii, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., May 1-3.
2016, P. Cross, U.S. Navy Wave Energy Test Site – Project Overview and Early Research, Presented at the Energy Harvesting Workshop, Arlington, Virginia, September 6-7.
2016, P. Cross, WETS, Presented at the International Marine Renewable Energy Conference Panel, Washington, DC, April 25-27.
2016, N. Li, K.F. Cheung, P. Cross, L. Vega, Wave Energy Resource Characterization at the US Navy’s Wave Energy Test Site, Hawaii, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., April 25-27.
2016, P. Anderson, L. Vega, Wave Measurements at WETS: Comparison of Waverider and ADCP In-Situ Records, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., April 25-27.
2016, P. Cross, U.S. Navy Wave Energy Test Site – Research Update, Presented at the International Conference on Ocean Energy (ICOE), Edinburgh, Scotland, February 23.
2015, P. Cross, R. Rocheleau, L. Vega, N. Li, K.F. Cheung, Early Research Efforts at the Navy’s Wave Energy Test Site, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., April 27-29.
2015, K. Rajagopalan, G. Nihous, L. Vega, Development of a Numerical Wave Tank to Support WETS Activities, Proceeding of the Marine Energy Technology Symposium, Washington, D.C., April 27-29.
2015, G. Nihous, K. Rajagopalan, L.A. Vega, Numerical Modeling Tools in Support of WEC Device Performance Evaluation at the U.S. Navy Wave Energy Test Site (WETS), Presented at the Marine Energy Technology Symposium (METS), April 27-29.
2014, P. Cross, Research at the Hawaii Wave Energy Test Site, Presented at the International Conference on Ocean Energy (ICOE), Halifax, Nova Scotia, Canada, November 4.
2013, A. DeVisser, B. Cable, L. Vega, Wave Energy Test Site (WETS): Marine Corps Base Hawaii (MCBH), Presented at Energy Ocean International, Providence, Rhode Island, June 10.
2011, L.A. Vega, Hawai’i National Marine Renewable Energy Center (HINMREC), Proceeding of the IEEE OCEANS 2011 Conference, Waikoloa, Hawai‘i, September 19-22, INSPEC 12459011.
2011, L. Vega, Expansion of Existing Facility in Wave Energy Test Site (WETS) Marine Corps Base Hawaii (MCBH), Presented to the U.S. Department of Energy, February 11.
Baseline Assessment: U.S. Navy Wave Energy Test Site (WETS)
|Receptor||Study Description||Design and Methods||Results||Status|
|Marine Mammals||Environmental Assessment (NAVFAC 2014) for marine mammals.||Review of impacts to marine mammals.||The Proposed Action is not likely to significantly impact marine mammals during in water installation or decommissioning of the deep-water WETS berth infrastructure (due to collision hazard and sound) or operation and maintenance of the deep-water WEC devices (due to electrical leakage, heat, electric and magnetic fields, entanglement). |
Although more than 25 species of marine mammals may occur in the U.S. EEZ around the Hawaiian Islands, many of the species are found in deeper water (i.e., greater than 984 ft or 300 m) and are rare visitors to the project area. The general lack of marine mammals observed in the project area on a regular basis over time indicates a reduced risk of adverse impacts to marine mammals.
|Marine Mammals||Environmental Assessment (NAVFAC 2014).||Review of impacts to Hawaiian monk seals.||The Navy determined that Proposed Action is not likely to adversely affect proposed Hawaiian monk seal critical habitat. The WEC device structures themselves are not expected to hinder Hawaiian monk seal access to or through the area. The WEC devices may have acoustic signatures that may initially deter Hawaiian monk seals from entering the immediate area around the device (less than 50 yd [46 m] around the device), but that would likely not include the seafloor under the device because of the water depth, and Hawaiian monk seals are expected to quickly habituate to the presence of the WEC devices once they are installed. The Navy determined that proposed action may temporarily deter Hawaiian monk seals from entering an insignificantly small area immediately around a deployed WEC device, but given that the devices would be over 3,000 ft (914 m) apart, the impacts of the proposed action on the accessibility of the area for Hawaiian monk seals would be insignificant.||Completed|
|Marine Mammals||NOAA and BOEM Regional Study (Costa and Kendall 2016)||Review of marine mammals in the area around Hawaii||This chapter provides distribution maps for marine mammals observed in the U.S. waters of the Main Hawaiian Islands from 1993 to 2014 using data integrated from multiple sources and spatial predictive modeling. At least 26 species of marine mammal (one seal and 25 cetaceans) have been recorded across the project area, of which eight species are listed as Endangered.||Completed|
|Birds||NOAA and BOEM Regional Study (Costa and Kendall 2016)||Review of seabirds in the area around Hawaii||This chapter describes an assessment of the at-sea distribution of seabirds around the Main Hawaiian Islands (MHI). We analyzed at-sea visual sighting data collected by the National Oceanic and Atmospheric Administration’s (NOAA) National Marine Fisheries Service (NMFS) Southwest Fisheries Science Center (SWFSC) on shipboard surveys conducted during May and August-December between 1989 and 2012. We present the locations of sightings of 24 species, and for 14 of these species we develop spatial predictive models of relative density throughout the study area.||Completed|
|Invertebrates||Environmental Assessment (NAVFAC 2014)||Review of impacts to corals||There are no coral reefs at the location where the deep-water WETS would be installed. Two ESA proposed coral species, Montipora flabellate and M. patula, were found in the vicinity of the surveys of the existing shallow-water WET berth conducted by the Navy between 2003-2011. Although proposed ESA listed coral is present, the majority of the project area has very low coral cover that is sparsely scattered, and the occurrence of the proposed coral species is very infrequent, limited to the reef flat zone.||Completed|
|Invertebrates||NOAA and BOEM Regional Study (Costa and Kendall 2016)||Review of benthic habitats and corals around Hawaii||Approximately 75 percent of the shallow-water (<30 m) area around the MHI has been characterized using satellite imagery, although the percentage varies by island, with less area mapped around Hawaiʻi and the windward sides of Maui and Kahoʻolawe. Seventeen datasets from shallow reef monitoring programs were compiled into a standardized database of benthic cover. A qualitative assessment of the data indicates that percent cover of major benthic taxonomic groups (e.g., live coral, macroalgae) varies at both the island and local scales, with coral cover generally lower around the most northwestern islands. Recently published spatial predictive models of mesophotic hard coral distributions in the ʻAuʻau Channel provided maps of probability of occurrence for Leptoseris spp., Montipora spp. and Porites spp.||Completed|
|Reptiles||Environmental Assessment (NAVFAC 2014)||Review of impacts to sea turtles||The Navy determined that the Proposed Action may affect, but is not likely to adversely affect sea turtles during in-water installation and decommissioning of the deep-water WETS berth infrastructure and associated scientific monitoring equipment (collision hazard and sound), and operation and maintenance of the WEC devices (electrical leakage, heat, electric and magnetic fields, entanglement).||Completed|
|Physical Environment||Wave energy conversion (WEC) buoy impact on a wave field (Sea Engineering 2002)||Calculations to predict impacts of WECs||The results of this study indicate that the impact of six WEC buoys on a wave field will be minimal, and will not be noticeable or quantifiable given the randomness of the waves on any given day. There should be no impact on breaking waves or on littoral processes inside the surf zone.||Completed|
Post-Installation Monitoring: U.S. Navy Wave Energy Test Site (WETS)
|Stressor||Receptor||Study Description||Design and Methods||Results||Status|
|Collision||Marine Mammals||WET Marine Ecological Assessment, 2005 – 2007 and 2011||Visual observations made by diver||No threatened or endangered marine mammals were seen or hear within 500 m of the anchor base or power cable. There was no evidence that any monk seals had ever become entangled or entrapped in any of the equipment.||Completed|
|Noise||Marine Mammals||Environmental noise monitoring, described in the EA (NAVFAC 2014)||To passively receive sound data, three acoustic monitoring stations would be employed at various times throughout the WETS operational period. Each station consists of hydrophones (underwater microphone) encased in a waterproof covering that would be used to listen and record sounds emitted by the WEC devices. Each station would be 72 in (1.8 m) long by 6 in (15 cm) in diameter. They would initially be deployed near each WEC device (three hydrophones per device) and gradually moved further distances away to record noise attenuation patterns.||Planned|
|EMF||Invertebrates||WET Year 1 Biological Assessment (October 2003 – October 2004)||Visual observations made by diver along replicate transects and surrounding area||No changes in the behavior, distribution or concentration of mollusks, echinoderms or arthropods was observed along the transmission cable. All species seen within the transect corridor, and on or under the transmission cable itself, were also sighted in comparable concentrations outside the transect corridor.||Completed|
|Habitat Change||Fish||WET Year 1 Biological Assessment (October 2003 – October 2004)||Visual observations made by diver. Abundance calculated by counting fish in photos||All the fish species sighted at the buoy, anchor base, power conversion system, and along the transmission cable were commonly occurring Hawaiian species. The author had expected that large numbers of baitfish and sharks might be attracted to the buoy assembly. However, no large schools of baitfish and no sharks were sighted during any of the dives.||Completed|
|Habitat Change||Invertebrates||WET Year 1 Biological Assessment (October 2003 – October 2004)||Replicate quadrats on anchor base frame, inspected by diver||There was no visible evidence of macroscopic algae or invertebrate growth or settlement on anchor base. A slight, likely bacterial, film was observed.||Completed|
|Habitat Change||Reptiles||WET Year 1 Biological Assessment (October 2003 – October 2004)||Visual observations made by diver and from boat||No endangered hawksbill sea turtles (Eretmochelys imbricata) were sighted underwater or from the boat. No threatened green sea turtles (Chelonia mydas) were sighted underwater. No significant quantities of preferred green sea turtle forage were sighted on any of the dives. No surface sightings (from the dive boat) of green sea turtles were made within approximately 500 yards of either the buoy or the transmission cable.||Completed|
|Habitat Change||Fish, Invertebrates, Human Dimensions||Marine Ecological Assessment of impacts to marine natural resources, 2005 – 2007 and 2011 (Smith 2011)||Open circuit compressed air scuba dives were made to facilitate direct observations and data collection. |
- Coral recruitment in chain lockers
- Replicate transects along cable
- Fish ID and photos
|Algae, sessile and mobile invertebrates, fin fish, protected species and alien species have been evaluated over a period of nine years. The project location was originally chosen based on the low probability that there would be any significant adverse impacts to marine natural resources. Based upon standard techniques and criteria there have been no significant changes to any of the marine natural resources assessed between 2002 and 2011 at the test site.||Completed|