With the Biden administration's goal of deploying 30 gigawatts of wind energy off the nation’s coasts by 2030, more than 10 million homes could benefit from low-cost power.
Offshore wind energy, however, is still in its infancy in the United States, and developers are working to understand complexities—such as wind direction as well as atmosphere and ocean interactions with turbines—before they invest in technologies.
Now, a team of wind energy experts from several institutions has identified the scientific grand challenges surrounding offshore wind resources—specifically, gaps in models, data sets, and model validation.
Addressing these gaps could lead to more offshore wind development and deployment off the nation’s coasts.
Some of the team’s recommendations
- There are no substitutions for observations in the real atmosphere. For models to be fully successful, observations must cover a large set of conditions, from sea breezes to large-scale storms. This is especially true for the atmospheric boundary layer—the layer of atmosphere that comes in contact with the surface of the ocean, constituting a hostile environment—where obtaining measurements is challenging because very few seaworthy wind measurement platforms are available.
- Model validation spanning many time and space scales is most effective when coupled with observation sets that span those same scales. Large-scale offshore wind field studies that include measurements for winds, waves, currents, and temperatures should be spread across all seasons. While costly, these seasonal campaigns would result in a significant return on investment. The data can be used to evaluate models, provide physical insights into key atmospheric and oceanic properties, and inform turbine design standards.
- Long-term deployments at sea should use wind measurements similar to those common over land. The team recommended use of wind profilers for taking measurements of wind speed and directions at increasing altitudes in the atmosphere. Profilers could also take measurements of wind speed, direction, and turbulence over much of the atmospheric boundary layer. To obtain more robust offshore wind and wave forecasts, temperature and humidity profilers could be used to measure through the depth—from approximately 100 meters to a kilometer over the ocean—of the atmospheric boundary layer.
- Data assimilation methods and atmospheric wind energy models need improvements. The team recommended that new data assimilation methods be developed so that existing observations for short- and medium-range weather predictions could be best used.
The recommendations and observations of the team could bring more accurate wind energy resource assessments to help support investment decisions. Additionally, more accurate wind forecasts could support integration of wind power with the grid.
This research was supported by the Department of Energy’s Wind Energy Technologies Office.