Cause of Siemens Gamesa blade shipment disaster revealed

Crash at Denmark's Port of Esbjerg destroyed blades destined for RWE's Thor offshore wind farm, currently under construction in North Sea

The cause of a calamitous Fred. Olsen Windcarrier vessel crash that destroyed Siemens Gamesa blades headed for a North Sea offshore wind farm has been revealed.

The incident involved the Brave Tern, a wind turbine installation vessel owned by Fred. Olsen Windcarrier.

On 10 June, Brave Tern was transporting what appeared to be nine blades for Siemens Gamesa’s flagship 14MW turbines from the Port of Esbjerg in Denmark. These blades were destined for the 1.1GW Thor offshore wind farm, which German power giant RWE is developing in Danish waters.

As the vessel manoeuvred to exit the harbour, the blades crashed into the Wind Keeper, a vessel operated by Denmark’s Cadeler. That led to Brave Tern colliding with infrastructure on the quay side, further wrecking the blades.

The slow-motion crashes, which occurred over the course of several minutes, were captured by workers on the quay side.

Today, the owner of Fred. Olsen Windcarrier, Norwegian holding company Bonheur, shed more light on the incident and its aftermath in its latest quarterly report.

Bonheur said that “no technical or capability issues” were identified with the vessel.

The “direct cause” of the incident was “found to be lack of situational awareness on the bridge during pilotage, leading to too small clearance.”

A preliminary inspection report issued last month by the Danish Maritime Authority, which said it was “not completely clear” why the crash occurred, included a minute-by-minute account of the incident.

An account from Brave Tern master Vignir Jonsson described growing alarm on the bridge as crew members initially believed the blades would clear Wind Keeper, only to realise too late how “dangerously close” they were getting to the Cadeler vessel.

Bonheur said that one person was sent to hospital for a precautionary check after the crash and that the vessel was ready to return to service after three weeks of downtime.

This downtime may have been a factor in the utilisation rate of Fred. Olsen Windcarrier vessels dipping from 72% to 70% in the last quarter.

This downtime appears to have had a knock-on effect on the earnings of Bonheur, which saw its net profit in the second quarter drop to NOK 372m ($38m), down from NKr 920m a year ago.

Its wind service division logged earnings before interest, taxes, depreciation and amortization (Ebitda) of NKr 326m, versus NKr 584m for the same period last year. The unit, which owns four wind turbine installation vessels, has a contract backlog of €1bn ($1.1bn), up from €357m a year ago.

There was better news for another Bonheur company, Fred. Olsen Renewables, which saw its operating revenues increase to NKr 519m, up from NKr 399m the same quarter last year. Its Ebitda nearly doubled to NKr 252m from NKr 127m.

Bonheur is also the owner of the holding company for DN Media Group, the publisher of Recharge.