Abstract
Jasco Applied Sciences was contracted by Statoil to conduct a continuous underwater acoustic recording programme in order to attempt to identify any discernible underwater acoustic signature from the HYWIND floating wind turbine and structure at the HYWIND test site to the West of Stavanger. In addition to recording at the HYWIND site, Statoil also requested that an identical recording configuration be conducted at a control site with comparable natural environmental conditions, 10km from the HYWIND test site (Figure 1). Both sites are relatively close (within several kilometres) to two local shipping fairways which pass closer to the HYWIND site than the control site.
The recording programme was structured to provide two, 75 day continuous recording periods using a bespoke mooring system and JASCO’s Autonomous, Multi-channel, Acoustic Recorders (AMARs) to provide wideband recording and to achieve a client-specified mid-water column recording geometry relative to the HYWIND structure. Both recording periods for each of the recording sites returned 100% continuous acoustic data which was extracted from the recorders and combined with third-party AIS and METOCEAN data and delivered to Statoil on two external hard disk drives for archiving and analysis.
This report provides ambient data analysis for the HYWIND data set, as well as an initial review of three events that JASCO believes are associated with the HYWIND structure. The ambient analysis includes for each deployment and each mooring:
- Plots of the hourly peak amplitude
- Plots of the hourly peak sound energy
- Two-month summary spectrograms, band-level plots and percentile plots.
- Two-week detailed spectrograms, band-level plots and percentile plots.
JASCO has also provided processed data files providing minute-by-minute data for:
- 1/3rd octave levels
- Decade band levels
- Total broadband level
- RMS and peak sound levels
- Number of shipping-like tonals present
- Number of seismic pulses detected, and max seismic pulse SPL.