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January 2014 Issue

Advancing Ocean Renewable Energy In the United States

By José Zayas
Director, Wind and Water Power Technologies Office,
U.S. Department of Energy

The U.S. Energy Department's Wind and Water Power Technologies Office is committed to advancing the development of energy technologies that harness the nation's ocean renewable energy, including offshore wind, wave, tidal and ocean current resources.

With more than 4,000 gigawatts (GW) gross energy resources (four times the nation's installed electricity capacity) within 50 miles of U.S. coasts, offshore wind has the potential to become a major source of clean energy if only a small portion of that resource is actually tapped for electricity production. Tidal and wave energy are renewable resources that can be harnessed wherever changing tides, waves or currents move a significant volume of water. The Department's nationwide wave and tidal energy resource assessments from 2012 identify a technical resource potential of up to 1,400 terawatt-hours of generation per year. For context, 1 terawatt-hour of electricity is enough to power 85,000 homes. Nearly 80 percent of the U.S. electrical demand comes from coastal and Great Lake states, with many of them having major U.S. cities with access to domestic clean energy resources.

Coastal states tend to have high electricity rates and, in areas such as the Northeast and mid-Atlantic, have carbon-intensive electricity supplies with limited local options for clean energy production. Ocean energy offers these states a significant new energy option that can provide as a hedge against fluctuating fuel prices, omitting the need for long-distance overland transmission. It is expected that ocean energy systems, similar to land-based wind, can provide coastal states the opportunity to revitalize the manufacturing sector.

Offshore Wind Deployments, Demonstrations
While the U.S. has no utility-scale offshore wind installed to date (construction on Cape Wind in Massachusetts is slated to begin in 2014), aggressive renewable energy and carbon reduction targets in Europe have driven the deployment of more than 10 GW of offshore wind from more than 3,000 individual multimegawatt turbines either producing power or currently under construction, according to the Energy Department's National Renewable Energy Laboratory. In a major step toward development of U.S. projects, the Interior Department's Bureau of Ocean Energy Management (BOEM) conducted two lease auctions in 2013 for parcels in designated offshore Wind Energy Areas, one off the coast of Massachusetts and Rhode Island, the other off Virginia.

To effectively develop the vast U.S. offshore wind resource, technology innovations are needed to lower system costs and address site-specific requirements, such as hurricanes in the Gulf of Mexico and the Atlantic, icing in the Great Lakes, and deep waters in the Northeast, Great Lakes and West Coast. In addition, environmental impact assessments, multiuser planning and transmission grid interconnection strategies are required.

To meet these challenges facing offshore wind, the Energy Department has initiated a program of collaborative research with industry, academia and national laboratories.

Advanced Technology Demonstration Projects Underway. In 2013, the Energy Department finalized awards for support of the initial design and permitting phase of seven competitively selected offshore wind demonstration projects. Through cost-share funding, technical assistance and interagency coordination to accelerate the deployment of these projects, the Department intends to validate new technologies to reduce costs, eliminate uncertainties and mitigate risks to support growth of a robust offshore wind energy industry. In 2014, the Department plans to select up to three of the seven projects to support, with up to $47 million in additional funding each to progress through final design, fabrication, construction and, finally, to full operation. These projects are anticipated to be grid-connected by the end of 2017.

The Department's demonstration projects are located in the Atlantic, Gulf, Pacific and Great Lakes. As there are differing design conditions in each of these regions, the project awardees have proposed a range of innovative technology solutions to realize the full potential of the offshore wind resource in each area. Three of the projects include floating platforms for deepwater deployment, while the remaining four projects have fixed-bottom foundation structures incorporating advanced designs such as twisted jacket structures. Collection of the baseline metocean, bathymetric, environmental and geotechnical data needed for project planning is being conducted at project sites. When completed, projects will be well-instrumented and required to collect and share data for five years post-commissioning.

First Floating Turbine in the United States. In May 2013, the University of Maine launched the first ever U.S. grid-connected floating wind turbine on an innovative semisubmersible concrete support structure with partners Maine Maritime Academy and Cianbro. While the University of Maine is one of the Department's demonstration projects awardees, work on this scaled deployment began earlier under a separate Department award. The 1:8 scale system supports a 19.8-meter-tall, 20-kilowatt turbine with a 9.6-meter-diameter rotor. This prototype will provide operating experience and concept validation for development of a novel, full-scale, multimegawatt floating wind platform.

Large-scale Component Test Facilities in Operation. Two Energy Department-supported projects, the Clemson University 7.5- and 15-megawatt (MW) Dynamometer Facility in Charleston, South Carolina, and the Massachusetts Large Blade (to 90 meters) Test Facility, have established world-leading test capabilities needed to carry out predeployment validation of innovative large system components. The Large Blade Test Facility has been carrying out accelerated lifetime testing for industry clients since 2011. The Clemson Dynamometer was dedicated in late 2013 and has several manufacturers lined up to use the facility to test large-scale turbine drivetrains.

Industry Resources Issued. To provide well-researched, objective information for decision makers faced with critical decisions related to project design, permitting or support infrastructure development, the Energy Department has funded a series of reports and Web-based assessment tools. A number of these resources for offshore wind energy stakeholders were released in 2013 and are available on the Department's website at wind.energy.gov/offshore_wind.html, including Offshore Wind Market and Economic Analysis; Manufacturing and Supply Chain Development; Optimized Installation, Operation and Maintenance Strategies; U.S. Vessels Requirements; Wind Ports Readiness Assessment; and Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems.

MHK Deployments, Demonstrations
The Energy Department is leading the nation's clean energy frontier with research and development to improve performance and lower cost of marine and hydrokinetic (MHK) technologies that capture energy from waves, and tidal, ocean and river currents.

System Performance Advancement Projects. This past August, the Energy Department announced approximately $13.5 million for eight projects to help U.S. companies develop durable, efficient wave and tidal device components that will reduce overall costs and maximize captured energy once integrated with the system. They will develop new drivetrain, generator and structural components, and develop software that predicts ocean conditions and adjusts device settings accordingly to optimize power production. The full list of selected MHK system performance advancement projects can be found at www.eere.energy.gov/water/news_detail.html?news_id=19575.

Department of Defense Partnership. The Navy's Wave Energy Test Site (WETS) off the Marine Corps Base Hawaii in Kaneohe Bay is expanding to three permitted test berths to provide a year-round test site for wave energy conversion (WEC) devices in the United States. In addition to the existing 30-meter-depth test berth, two test berths at 60 and 80 meter depths are planned. The facility will be able to test as many as three WECs simultaneously, up to 1 MW in size. In early 2014, Northwest Energy Innovations (Portland, Oregon), with support from the Energy Department, plans to demonstrate its wave energy device for one year at WETS at the 30-meter test berth. These activities highlight the Energy Department's ongoing partnership with the Navy and its continued technical support to test and evaluate wave energy options for powering U.S. Department of Defense facilities.

Energy Department National Laboratories Highlighted Examples. The Department's national laboratories developed a methodology for MHK technology design and economic analysis that will advance MHK technologies. The project establishes baseline cost of energy for six device designs, called Reference Models, by designing, predicting performance and creating publically available cost models. The Reference Model reports are available at http://en.openei.org/wiki/Gateway:Water_Power.

The National Laboratories are developing WEC-Sim, an open source code that simulates the power performance of wave energy converters and encourages innovative designs. A newly launched online coding competition will produce a code module for WEC-Sim: Open Wave Analysis and Response Program (OpenWARP): Predicting Hydrodynamic Forces for Renewable Ocean Energy (www.topcoder.com/openwarp).

Enabling Ocean Renewable Energy Development
Removing market barriers in order to promote the expansion of the ocean renewable energy industry is an integral component of the Department's work in this field. Such work includes research to ensure that these technologies are effectively deployed and promote environmental stewardship.

Supporting Novel Environmental Research Through Partnerships. Last August, in partnership with BOEM, the Department awarded $2.4 million to nine projects to address key environmental data needs associated with potential effects of wave and tidal energy devices. Projects were awarded under two topic areas: studies that gather important data and monitor for environmental effects around deployed MHK devices, and studies that synthesize existing data from appropriate surrogate technologies with stressors and receptors similar to those expected from MHK devices. These projects focus on gathering information to understand the relative effects on a number of environmental topics, including characterizing device-generated noise and its potential effects on marine mammals and fish behavior, understanding static and dynamic interactions that wildlife have with tidal turbines and using models to predict interaction, and assessing the potential effects that electromagnetic fields associated with power from MHK devices may have on marine species.

Additionally, interagency collaborations with BOEM are working to develop a research campaign to better understand the environmental effects of the rapidly developing offshore wind industry, beginning with a joint request for information. Collectively, these research and collaborative efforts aim to provide quality data in order to ensure the sustainability of ocean renewable energy technologies and expedite the permitting process, ensuring the successful growth of the industry.

Advancements in Ocean Energy Environmental Research. Last year, the Energy Department supported efforts by the Biodiversity Research Institute and Stantec Consulting to conduct major baseline studies that quantify the abundance, distribution and movements of key marine species in high-priority offshore wind energy areas, helping to inform offshore wind siting and provide data that can be used in the offshore wind permitting process. Additionally, through Oregon State University and its team partners, the Energy Department is supporting the development of a monitoring package to detect bird strike with offshore wind turbines by integrating data received from multiple types of instrumentation.

Based on the Department-funded research that the Electric Power Research Institute conducted over the last several years, a comprehensive research report was released in June that summarizes several experiments evaluating impacts to fish after passing through several hydrokinetic turbine designs. Results of these studies conclude that fish are able to avoid turbines, resulting in very low mortality rates.

All of these reports and studies can be found on the Energy Department-PNNL Tethys website at http://mhk.pnnl.gov/wiki, which features additional information on environmental effects of renewable ocean energy development.

Looking Ahead
The Wind and Water Power Technologies Office will continue to make key investments to ensure that the cutting-edge research portfolio will produce the next generation of ocean renewable energy technologies and jump-start private sector innovation critical to the country's long-term economic growth, energy security and international competitiveness. More information on the Energy Department's current activities is available at http://wind.energy.gov and http://water.energy.gov.

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