Offshore Wind – Powering the Future
New, climatologically representative simulations with the Weather Research and Forecasting (WRF) model of meteorological conditions over offshore wind energy lease areas along the U.S. east coast, and likely electrical power production and wake-induced power losses from those prospective wind farms. The ensemble of simulations is uniquely detailed relative to past research in that the simulations are climatologically representative (rather than case studies), cover the entirety of the U.S. east coast, include two wind farm parameterizations, and sample across four different wind turbine deployment scenarios and hence installed capacity densities. Mean system-wide capacity factors (a metric of power production from wind farms) for the U.S. east coast lease areas considered range from 39–55% across the four layouts and two wind farm parameterizations (WFPs). If 15 MW wind turbines are deployed at a spacing of 1.85 km in all lease areas considered here, they are projected to provide 3.5 to 4.4% of U.S. national electricity demand. Although the largest cluster of lease areas considered covers 3675 km2, the projections of wind power density (watts of electricity produced per square meter of lease area) increments across the range of ICD considered (3.5 to 6 MWkm−2) and lies between 2 and 3 Wm−2, which implies that the scale of deployment considered here has not reached power production limits imposed by the rate of kinetic energy replacement.
Global wind energy installations offshore increased to over 50 GW by the middle of 2022, and an additional 40 GW may be added by the end of 2025. Optimization of offshore wind farm location and design is increasingly becoming a three-scale process: (i) Identification of offshore areas suitable for wind turbine deployment (i.e., regional resource assessment), (ii) selection of specific lease areas for auction and development within that region and (iii) selection the exact layout and wind turbine for each wind farm. The offshore wind energy deployments being developed along the U.S. east coast far exceed those that characterize existing offshore wind energy deployments and so are expected to experience greater wake losses. For example, the developments that are being undertaken in the offshore wind energy lease areas south of Massachusetts and Rhode Island cover a combined area of 3675 km2 and will comprise between 13.5 and 22.3 GW of installed capacity (IC, depending on the layout selected). This IC is five to eight times that of the largest combined wind farm. Hence, there is a need to advance understanding of, and predictive models of, power production plus wake production and propagation from these multi-GW installations.
The world’s first offshore wind farm was installed in the coastal waters of Denmark and commenced operation in 1991. At the end of 2020, 6600 wind turbines were deployed in European waters in over 112 wind farms. Data from the GWEC indicate 6.6 GW of new installed capacity was added during 2022, taking the global offshore IC to 64.3 GW. The pipeline of offshore wind energy projects in the U.S. is > 40 GW of installed capacity. GWEC global projections are for IC additions within the next decade (2023–2032) of >390 GW. The increase in offshore wind energy installed capacity is being primarily driven by three factors: (i) Increased number of wind turbine arrays. (ii) Increased number of wind turbines being deployed in each array. (iii) Increase in the physical dimensions and rated power of wind turbines. As shown herein:
- The atmospheric conditions in this area are substantially different from those in the North Sea and yield higher projected power production efficiency than offshore wind farms in Europe.
- Substantial uncertainties in power production efficiency derive from the use of different wind farm parameterizations.
- The offshore wind farms being developed along the U.S. East Coast are a factor of 5 to 8 larger than those operating in Europe, and so optimal wind farm layouts (ICD) may not be identical to those in Europe.