A high-voltage substation as a 'construction kit'

Optimal construction speed and quality 

Construction of the new 380 kV high-voltage substation near Tilburg is in the hands of Cooperation Croonwolter&dros - Mobilis (SC&M). Work started at the beginning of this year. To optimize the lead time, SC&M is working with Mobriq; a self-designed modular design with many prefabricated components. Jochem Mol and Rik van Opdorp, both project directors, explain how they approach the cooperation and construction.

"In outline, we have been commissioned for the engineering, construction and realization operational delivery of the entire 380 kV substation," explains Rik. "The new high-voltage substation consists of thirteen fields and three transformers that convert the current from 380 kV to 150 kV. This requires the necessary construction to make this possible." Jochem: "From TenneT's basic design, we as SC&M are responsible for working out the final design and implementation design. From that execution design, we will realize the project. In the first phase of the project, Strukton and Gubbels have already prepared the site for construction. We will follow this up in the next phase. We will start installing bored piles and foundations. Nothing will be driven, but everything will be drilled because of the badger sett. Then we apply the field foundations using the Mobriq system. This is a modular system consisting of prefabricated beams that together form a pattern that allows us to build fields quickly and efficiently."

Modular construction with Mobriq

The Mobriq system was "born" out of the desire and urgency to build "differently. In fact, the new high-voltage substation near Tilburg is part of the TenneT EU303 program. An extensive expansion and renewal program of some 360 high-voltage substations in the Netherlands. To be able to realize this, construction must be efficient. Rik: "From SC&M, we developed Mobriq, a modular concept that significantly shortens the lead time of both the design process and on-site conversion. It is a modular design using many prefabricated components already prepared in the factory. Basically, it consists of two types of concrete beams with standard upstands and standard distances. A crane can lay a layer of Mobriq beams for two fields within a day. We developed this system based on lessons learned from our previous experience with TenneT projects. We knew exactly where the bottlenecks were, so we started working on them, resulting in the Mobriq system. It is partly thanks to Mobriq that we are meeting the tight time schedule in Tilburg."

Until testing

Rik: "In addition to installing the field foundations, we do the concrete work for the lightning surges and the basement boxes for the transformer and coil cells. Once the first civil engineering steps have been taken, we will then install the steel and high-voltage components, on top of that the primary components. Then we can get to work on the control and power supply, in black and white terms: pulling cables and connecting them. And last is the phase of testing and commissioning the station. In parallel, we build three transformer coil cells so that we have them ready to place the transformers. We are installing the field houses, a central service building that houses all the technology to control the station, and three transformers. When this is completed later in 2026, we will install fencing. Nice to mention is that we are constructing a wadi to collect rainwater at the high voltage station. Here the water can drain away on our own property. In the station we are laying grass tiles made of recycled plastic. Because the grass has to grow in small squares, it stays smaller than normal and immediately provides a stable surface to safely walk on to inspect components."

Collaboration expanded

Croonwolter&dros and Mobilis are working on this project from a partnership. Jochem: "We have set up a single project organization, popularly called the Dome. This includes the right people from both organizations who have made the integral design to the implementation level. On the basis of this design, both parties start working in a multidisciplinary way, with the entire management of the project also being integrated. For the past five years, we as SC&M have been active for TenneT. But this is the first new-build 380kV high-voltage substation that we design and build completely from A to Z, so civil, primary, secondary and tertiary. The beauty of the collaboration is that we all go hard at it together, are open in our communication and dwell on successes."