CADWorx & Analysis Solutions

Operating in 14 countries across Central Africa, Latin America, Southeast Asia and Europe, Perenco is a leading independent oil and gas company active across the full lifecycle of energy projects, from exploration to decommissioning.

The company prides itself on its entrepreneurial spirit: “Our company is one of a kind, just like the made-to-measure solutions we create. We do things differently,” says François Perrodo, the company’s chairperson. 

The conception of the Tchendo 2 gas platform, inaugurated in 2023, is a great example of how this spirit is put into practice. It also shows how precision scanning, high-quality design tools and fast-moving collaboration are a powerful combination that can bring revamping projects online in record time.

An Old Platform Gets a New Life

For this project, which began in March 2021, Perenco partnered with Aentec. 

Instead of designing and building a new platform from scratch, the companies opted for a rare strategy: repurposing a drilling platform, originally built in Dunkirk in 1982 and shipped to the company’s Middelburg site in the Netherlands, into an electrical generation platform.

At the Dutch shipyard, Aentec carried out a high-precision 3D laser scan, accurate to within two millimeters. The team used Hexagon’s BricsCAD and CADWorx Plant Professional software to model the structure and prepare it for its new life: generating 27 megawatts of power through three gas turbines, along with a new bridge and upgraded systems.

“On such a project, precision is essential—in this case, we’ve scanned the platform with a precision of two millimeters,” said Aentec’s General Manager Nourredine Echtioui. “But visual fidelity also plays a role. For example, we ensure that essential components such as pipes, equipment, and valves are displayed in their actual colors within CADWorx. This minimizes the risk of misunderstandings and errors, making it easier for the client to navigate this complex 3D model.”

A Collaborative and Iterative Process

Once the initial scan was complete, Aentec and Perenco used CADWorx to collaborate and iterate rapidly: “With CADWorx, we could collaborate very easily and exchange 3D models and piping classes with Perenco. It saved us time, made us more efficient, and Perenco was able to make immediate use of the models, generate isometrics and make all the changes they needed,” Echtioui added.

Project Manager Sylvain Bouvard emphasizes how the software allowed them to anticipate and visualize updates: “Even before structures are detailed, we were able to import client data and visualize how it would look. It was particularly important for a project like this that included significant work on metal structures. In addition, we were able to adjust rapidly to any changes or new input from the client side.”

New components, like cranes or turbines, were integrated easily into the 3D environment as DWG files, reducing design lag. The full engineering scope included modeling piping and equipment, conducting detailed surveys and performing structural calculations. In total, more than 1,500 tons of steel structures and hundreds of kilometers of piping were managed through the model.

High-Fidelity Designs Eliminate Surprises and Rework

That level of precision paid off. “We didn’t have the gaps that you traditionally observe between the designs and the construction. When we visited the site to perform the final, as-built scan, we were able to see all elements fit into the exact space that had been designed,” Echtioui said.

The benefits cannot be overstated: on such a platform, every component is fabricated onshore, shipped by boat and assembled on-site. Any design error can result in expensive and time-consuming adjustments, and rework can cause months of delay.

As a result, the full project—from the first scan to a functioning offshore power platform—took just a year and a half. Traditional timelines can easily stretch to twice that.  

Beyond construction, the digital models now help streamline operations. They support simulation and staff training, without the need to step foot on the platform.

For Aentec, which has now worked with Perenco on nearly a dozen platforms, Tchendo 2 remains a standout. “There aren’t many projects like this in a career,” said Echtioui. “Scanning the existing platform, carrying out the transformation studies, then returning to the Netherlands with the team to see the completed work and perform the as-built scan based on our studies—all within less than two years—is something rare. There aren’t many projects like this in a career. I’m grateful to the Perenco teams for their trust and professionalism.”