Breezes blowing off the U.S. east and west coasts are strong and in good supply. These winds offer a low-cost source of energy that, when finally harnessed, could provide more than 2,000 gigawatts of power to U.S. electricity consumers.

Since 2011, the U.S. Department of Energy’s (DOE’s) Wind Energy Technologies Office (WETO) has allocated more than $200 million for development of strategies and technologies to capture wind for national energy use. Key in this effort is the expertise of wind researchers at the DOE national laboratories, including PNNL, which manages the development and deployment of capabilities and technologies that are helping WETO glean offshore wind for energy purposes.

Buoys for wind measurements

PNNL oversees two buoys (link) equipped with advanced scientific lidar and sensor instrumentation that can obtain meteorological and oceanographic measurements in offshore locations. Measurements include average wind speed, direction, and gusts at six different heights; wave height, period and direction; and air temperature, pressure, humidity, and dew point. Data obtained from buoy deployments—for example, from the coasts of New Jersey and Virginia—are helping to inform wind plant technology development and siting. In fact, analyses performed by PNNL on the data from these deployments has resulted in the first publication of observational data for wind roses—a succinct view of how wind speeds are typically distributed at a particular location—at hub height over a full annual season cycle offshore in the United States (link to report). Data from the buoys are physically retained on the buoy during a deployment. Depending on available communications bandwidth, a subset of the data is transferred in near real time to DOE’s Atmosphere to Electrons Data Archive and Portal (link), where they are available to the user as well as to the rest of the wind energy community.

The buoys are now being deployed off the coast of California for the Bureau of Ocean Energy Management. This deployment, occurring in the summer of 2020, reflects strong cooperation between DOE and the Department of the Interior in supporting the development of wind off the U.S. West Coast. The buoys will be on location for a year off California’s Humboldt County and Morro Bay.

In an effort to maximize the benefit from the buoys, PNNL has also developed and administers a loan program (link) for these systems. The program enables non-federal organizations to use the buoys and associated instrumentation for their own research and development programs consistent with DOE’s mission of advancing offshore wind technology for the nation.

Tracking bird and bat behavior

PNNL engineers have developed a software technology called ThermalTracker (link) that tracks behaviors of birds and bats offshore. The technology uses 3-D thermal imaging during day, night, and in limited visibility conditions to track flight patterns and physical attributes. The goal—to evaluate effects of wind plant technology on bird and bat behavior and help operators make the best decisions related to environmental impacts or siting.

PNNL engineers are also developing radio frequency transmitter tags that can track bat behavior around offshore wind turbines. The transmitters are of minimal size so as to not harm the tiny bat species but will have more extensive service life and detection range than previous tag technologies.

Working with other national laboratories and industry

PNNL is partnering with the National Renewable Energy Laboratory (NREL) on a multi-year collaborative effort to facilitate knowledge transfer for offshore wind research around the world to synthesize key issues and disseminate existing knowledge about environmental effects and prioritize future research needs. This includes examining the state-of-the-art methods and technologies that are relevant to the nation’s offshore wind environmental issues. Research focuses include environmental stressors (e.g., noise, electromagnetic fields), receptors (e.g., fish, birds and bats, marine mammals), environmental monitoring technologies, and cumulative impacts.

Finally, PNNL is working with NREL and the New York State Energy Research and Development Authority, as well as DOE’s National Offshore Wind Research and Development Consortium to address technological barriers and lower costs and risks of offshore wind in the United States. This consortium is designed to facilitate development of the offshore wind industry by addressing wind resource and physical site characterization. In addition, the consortium investigates solutions for installation, operations, and the advancement of wind plant technology.