Abstract
Floating offshore wind farms represent a major advancement in renewable energy, enabling deployment in deepwater regions with stronger wind speeds. By 2035, they could account for up to one-third of offshore wind energy production. Hywind Tampen, in 2025 the world’s largest floating offshore wind farm, consists of 11 turbines with 94.6 MW total capacity, supporting the decarbonization of offshore oil and gas operations and serving as a platform for environmental research.
This work synthesizes findings from a sound source characterization study of operational turbines and assesses potential impacts on marine life. Using a directional hydrophone array within the wind farm and two omnidirectional hydrophones outside, the study identified narrowband sound emissions below 200 Hz, with prominent tones at ~25 and ~75 Hz. Median broadband source levels ranged from 156.5 to 163.8 dB re 1 μPa2m2, approximately 3 dB lower than levels recorded in a previous study for smaller turbines at the wind farm in Hywind Scotland, indicating a nonlinear relationship between turbine size and sound levels. Transient, impulsive sounds from the mooring system, previously reported at Hywind Scotland, were absent. Noise modeling showed no risk of injury to fish or marine mammals, with temporary threshold shifts occurring only within 150 m.