The new substations will replace existing ones that have reached the end of their operational life. Recycled steel will be used, among other things, in the 110-kilovolt transmission line gantries where overhead lines are converted into underground cables.

Recycled steel will also be used for the outdoor masts supporting lightning protection and area surveillance systems. In addition, the switchgear will be built entirely without SF6 insulating gas, which is a potent greenhouse gas. The substations in Satakunta will feature so-called gas-insulated switchgear located indoors.

“For the first time in Finland, all outdoor steel structures of a main grid substation are being built from low-emission steel. It’s great to be piloting something new while at the same time helping to reduce both our client’s and our own value chain’s carbon footprint,” says Enersense’s Project Manager Sami Lehtimäki.

A total of over 80,000 kilograms of recycled steel will be delivered for the three substations.

Enersense assessed nearly a hundred suppliers to find suitable steel

Enersense’s experts conducted a comprehensive review of almost one hundred suppliers around the world to identify a suitable low-emission steel producer for substation construction.

“We aim for significant emission reductions throughout our value chain and want to help enhance our clients’ carbon handprint at the same time. We are continuously looking for more sustainable ways to build, and from now on we will always offer our clients a lower-emission alternative as part of every tender calculation,” Lehtimäki says.

Steel-related emissions account for roughly one-third of Enersense’s total carbon footprint, making the shift towards lower-emission steel a key element of the company’s climate work. Recycled steel typically produces around 40% less carbon dioxide compared to steel manufactured using the traditional iron ore–based process.

The three new substations in Satakunta are scheduled for completion between 2026 and 2027.