By David Graff, AAU Communication and Public Affairs
Photo: Personal

Sabotage and security around the undersea cables is a topic that is getting increasingly more attention in the Danish media. Something that Claus Leth Bak, cable expert and professor at AAU Energy is aware of. In a short time, he has become a widely quoted source in the Danish media, and he sees it as his obligation to share his knowledge about the undersea cables that are vital to Danish energy system.

"Whoever the saboteurs are, they also have people who know what I know. It's not that complicated. The nautical charts with the location of the cables are all publicly available. So I’m not revealing any secrets – I'm probably just saying it in a way that people can understand," says Claus Leth Bak. 

Speaking in pictures

There are many examples of this. Like when he explained to a newspaper that the cables which are laid one to two meters into the seabed, "snap like carrots" if the anchor from a 100,000-ton tanker gets hold of them. 

Or when he said on the TV News that "a cable has two ends" – the implication being that a cable break has consequences in not just one, but two places. So it’s always more than one country's problem, and requires cooperation. 

"I actually find it difficult to understand researchers who don’t share their knowledge. In my view, we have both an obligation to speak out and to conduct research on something that can offer concrete value to the communities around us," he says.

 The desire to contribute something concrete has been a driving force for Claus Leth Bak ever since he dreamed as a child of becoming a farmer. And when he graduated in 1994 with an MSc in high-voltage engineering, the research path was not his first choice either. 

"I had to go out to use my education for something, so I was employed for six years at Nordjyllandsværket [North Jutland Power Plant] which I helped to build up," he explains. 

Knowledge must be useful

At some point, however, Claus Leth Bak's former professor lured him back to the university. Today, he is, in his own words, "a country bumpkin with the title of professor'". He is still concerned that his knowledge be used for something. This is clear in his last message: 

"In the green transition, it may seem like a big step in the wrong direction not to close the conventional power plants as planned. However, it is common sense in terms of security of supply to keep these for emergency preparedness until the threat to Denmark's critical energy infrastructure is normalized," he says. 

If the cables to our neighbouring countries are sabotaged, the reliability of the electricity supply will be threatened, especially because it takes up to a year to repair a high-voltage subsea cable. 

"Today, the electricity system will actually very likely collapse if just two of the large power cables on the seabed are destroyed at the same time. We are vulnerable when we don’t have a backup source," says Claus Leth Bak.