A projected increase in offshore wind farm development bodes well for rising levels of renewable energy penetration into power grids. The expanded development of such energy systems and the ever-growing size of wind turbines pose challenges for optimal siting of offshore turbines to efficiently achieve electricity generation goals. Data from prospective leasing areas off the northeastern U.S. coast was analyzed by Offshore wind farm lease areas along the U.S. east coast considered in the study. Source: Sara C. Pryor et al./Cornell UniversityOffshore wind farm lease areas along the U.S. east coast considered in the study. Source: Sara C. Pryor et al./Cornell UniversityCornell University researchers to examine power production, wind-farm wake intensity and extent, and wake-induced power losses from planned large offshore wind farms.

The analysis published in Joule uses a flow-scenario method to examine the operation of 15 MW wind turbines with spacing equivalent to the European average. These systems are found to account for electricity production of 116 TWh/year or 3% of current U.S. national supply, but production is reduced by one-third due to wakes caused by upwind wind turbines and wind farms, even when the turbine arrays are 15 miles to 50 miles apart. Thus, the wind turbines may fatigue earlier and a group of turbines may experience up to 30% lower power production due to wake effects.

Under some flow conditions whole wind-farm wakes can extend up to 55 miles downwind of the largest lease areas. Simulations including maritime corridors demonstrate reduction in the wake effects leading to power-efficiency gains and may offer contingent benefits.

Additional research is recommended to consider diverse wind turbine layouts and additional atmospheric flow scenarios to ensure optimal design of individual offshore wind farms.

To contact the author of this article, email shimmelstein@globalspec.com