Electric power replaces diesel in tunnel project

"These are the first dump trucks delivered in Norway that run on electricity, and they have the largest battery pack delivered in Northern Europe," says Torgils Rekve. He is the operations manager at AF Gruppen and works on the Oslo New Water Supply project.

Rekve stands in front of one of the Epiroc machines that were put into operation on the project in May. The dump trucks are used to transport stones inside the tunnel system. Using emission-free machinery inside the tunnel provides a better working environment for those working underground.

"The dump truck is also very quiet and comfortable for the machine operator," says project director Nils Ola Hoff.

The joint venture AF Ghella is in the process of building a part of Oslo's new water supply. The Oslo municipality's water and sewage department is the client.

The contract involves the excavation of an 18-kilometer tunnel where water pipes will be established. In addition, four large rock halls, two clean water basins, a pumping station, and a ventilation station will be built. Everything will be blasted out of the rock. The project is valued at 8.75 billion Norwegian kroner and is AF Gruppen's largest assignment ever.

Oslo municipality requires that the construction site be emission-free by January 1, 2025, and the use of electric dump trucks is a requirement from the client. For the project, this involves phasing in electric construction machinery as such machines become available. For transportation to and from the site, trucks running on biogas are used.

Nils Ola Hoff has worked in the construction industry since the early 1980s. He says that construction machinery has undergone rapid development in recent years.

"We want to be part of this development. It's important for AF to be at the forefront," says Hoff.

n addition to the dump trucks, electric wheel loaders and an electric grader have been put into operation on the project. The grader is the first of its kind in the world. The project management is continuously working to introduce new electric machines to replace fossil-fueled machines.

"Fuel represents a large part of our greenhouse gas emissions, and much of the fuel consumption is related to earthmoving. Therefore, it's especially important that these machines are electrified," says Nora Omdal Schjoldager, climate and environment manager at AF Anlegg.

"At the same time, we must consider a cost-benefit mindset, especially when it comes to reducing greenhouse gas emissions. For large machines, electrification is expensive and the waiting time is long, so it's important that we don't overlook other measures that could provide greater greenhouse gas reductions per dollar. As for personal vehicles, many projects have already electrified, and the replacement here is happening quickly."

Electrifying the machinery fleet is just one of many measures to reduce greenhouse gas emissions in construction projects. Reduced resource usage, low-carbon concrete, and changes in constructions can both lower emissions and minimize environmental impact. In the E6 Roterud-Storhove project in Innlandet, a new bridge concept was developed during the collaboration phase, saving the environment from emitting 20,000 tons of CO2 equivalents.

"Our industry contributes to significant greenhouse gas emissions, but that's precisely what is motivating. When the volumes are so large, even small changes result in significant reductions. We are starting to have better figures on our greenhouse gas emissions, both direct and indirect, and, together with the rest of AF Gruppen, we aim to halve greenhouse gas emissions in our projects by 2030," says Nora Omdal Schjoldager.