The power lines in the Hochtaunus and Main-Taunus districts are green, in the industrial park they are red.

And if there is a power failure at Frankfurt Airport, one of the connection points between the light blue lines, which the employees of the network control center of the energy supplier Süwag keep an eye on, lights up.

There are always three experienced colleagues around the clock, each monitoring the 32,000 kilometer network in Süwag's distribution area, which stretches across four federal states, including southern Hesse, on six screens each.

Inga Janovic

Editor in the regional section of the Frankfurter Allgemeine Zeitung and responsible editor of the business magazine Metropol.

  • Follow I follow

Your workplace in Frankfurt's Höchst district should seem like paradise to computer game fans: Slightly dimmed light, pleasantly cool temperature, a whole wall and every table full of screens, plus well-upholstered swivel chairs: This is a good place to gamble.

But of course this is anything but a game: five years of experience and training are necessary before an employee can take on a responsible shift.

Any longer failure would have fatal consequences

After all, every longer failure in the electricity or gas network, which is also monitored here, has fatal consequences;

and especially now that all infrastructure operators can observe how hackers try to get into their systems, the vigilance in front of the screens and in the IT centers is high.

This is one of the reasons why only selected employees have access to the network control center, the way leads through an isolation lock.

And because sensitive issues are involved here, Thomas Christ, head of the network management department at Syna, the Süwag subsidiary responsible for network operation, also omits a few details when he explains to visitors what they see on the many screens.

What the layman calls a power grid is actually several grids that carry different voltages.

According to Christ, the high-voltage network, which supplies the electricity in large quantities, is ring-shaped and therefore very fail-safe.

The medium-voltage grids that lead to the households are divided into individual groups and mostly grouped in a star shape around the 120 substations in the grid area.

Something can easily go wrong here, as well as in one of the 10,000 medium-voltage substations.

If this is the case, a gong sounds in the network control center, reminiscent of the grandparents' mantel clock.

The employees hear this noise several times a day, and then things happen quickly: the flow of electricity is diverted and a technician is alerted, who immediately responds.

The inspectors can use the mains voltage to see where the fault is and guide their colleagues there.

In most cases, electricity customers don't even notice breakdowns and repairs.

In Pleidelsheim near Stuttgart there are colleagues who do exactly the same thing as the people in Frankfurt: Süwag, which recently achieved sales of 1.9 billion euros and has around 1,000 employees nationwide, operates another monitoring center there.

Should one fail, the other would be fully functional and would have the entire network under control.

The shock is still deep

Working with a double bottom is standard for the operators of such important infrastructure, but that is not always enough.

If, for example, lightning or excavators - thunderstorms and civil engineering work are considered the main enemies of the pension providers - once again hit a line, it is inevitable that lights, refrigerators and machines will go out for a short or long time.

And in very rare cases everything goes wrong, as happened to Süwag almost a year ago.

To this day, the company, which belongs to the Eon Group and supplies a good 90,000 customers in Frankfurt and the surrounding area alone, is dealing with the consequences of the major power outage on October 26, 2021.