At one point in the nightly heavy transport, high-speed and the leisurely 405-tonne transport meet: the transformer, which the power grid operator Tennet has transported from a forwarding company from Fechenheim to the substation at Berger Warte on Thursday night, simply has to be turned on waiting at a railway barrier.

Not just until the ICE has raced by.

Instead, until one o'clock, rail traffic on this section of rail is blocked for an hour.

There are high safety precautions for the transport, since the total weight of 405 tons from the transporter and transformer and the bulky dimensions bring with them uncertainties.

But in the end everything went according to plan and around two-thirty the transformer was already very close to its destination, the “Am Galgen” substation.

Comprehensive modernization of the Frankfurt electricity distributor

Police and Tennet have patiently documented the way through the Frankfurt Night from Fechenheim via Hanauer Landstrasse and the Cassellastrasse level crossing on their Twitter channels.

The recordings are evidence of a rather leisurely affair that was carried out with great care.

A heavy-duty truck like this is not a sprinter.

With a total length of more than 43.5 meters, changes in direction must be planned foresightedly and intelligently.

The colossus was manufactured by General Electric in Mönchengladbach on behalf of the power grid operator Tennet.

From there he took the train to the Hanauer Landstrasse marshalling yard in Frankfurt-Fechenheim. 

The background to the transport is a comprehensive modernization of the Frankfurt electricity distributor, which has become necessary, among other things, as a result of the switch to renewable energies and green electricity. The infrastructure continues to gain in importance. Tennet announced that the increasing demand for electricity in households, industry and data centers had to be met. And future-proof systems are required to transport the “green electricity” from northern Hesse and the coastal areas in northern Germany to the Rhine-Main region.

The substations link Tennet's 220,000-volt level with the 110,000-volt network of the local operators, through whose lines the electricity then reaches the consumers. You can imagine the whole thing like motorway exits that lead from the electricity highway to the federal highways of the distribution network operators. The heart of the substation are the transformers, which bring the electricity to the lower voltage level. If necessary, the devices can also work in the opposite direction in order to transport locally generated green electricity.

The large device that has now been delivered is one of four new transformers that are required for the modernization of the "Frankfurt-Nord" substation.

Each of these grid coupling transformers, each with an output of 300 megavolt amperes, can mathematically transform electricity for around 400,000 households.

Tennet is investing a total of around 45 million euros in the site.

The conversion of the 220/110 kilovolt system, which was built in the sixties and seventies, should be completed by 2025.