—— HVDC stations testify to how the energy transition is being driven forward on the high seas.

Offshore wind parks generate almost one fifth of the total wind power in Germany. To get this clean energy from the sea to the coast, the alternating current that is generated must be converted into direct current. Of the two, only the latter can be transported ashore — through undersea cables as thick as an arm — without major losses. If the energy were sent as alternating current, hardly any of it would be left after the eighty-­kilometer trip through the lines.

The current is converted at sea by gigantic converter platforms like the BorWin 3 (large photo) or HelWin 1, which are connected to transformer stations on land, to which the electricity is transmitted. TÜV SÜD has been inspecting both the onshore and offshore facilities since early 2020. Our experts take a close look at the cranes and elevators, fire alarms, fire extinguishing and tank systems, and various pressurized containers. “We can offer a one-stop shop for all the expert testing in accordance with Germany’s Industrial Safety Regulations,” says Group Manager Timo Brenneisen in the Offshore Wind Energy Division in Hamburg. This view of the big picture is something customers appreciate — and helps set TÜV SÜD apart from the competition.

“It’s incredibly interesting from a technological point of view and there’s an excellent working atmosphere.”

Timo Brenneisen

Anyone wanting to work as an expert inspector out on the open sea must be physically fit and have taken ocean survival training. “For instance, there’s very practical training on how to survive extreme situations like a helicopter crash at sea or a fire on the platform,” Brenneisen says. The assignment itself starts with a safety briefing at the airport. After that, a helicopter flies the team out to the station. The inspectors usually stay on board for three to five days, during which they work in close cooperation with the maintenance crews there.

“Admittedly, it can get uncomfortable out at sea,” Brenneisen says. On the other hand, the work is extremely interesting and satisfying because the technologies being used offshore are ones you never get to see on land. He continues, “It’s incredibly interesting from a technological point of view and there’s an excellent working atmosphere.” Everyone working on the station has a similar mindset and a commitment to the same goal: the sustainable energy supply of the future.

INNER LIFE OF A STATION An interior view of the converter station ­HelWin 1 in Büttel, Schleswig-Holstein, Germany. Commissioned in 2015, the station has a capacity of 576 megawatts—which is enough to supply more than 700,000 households.