A massive reconstruction of the 400/220 kV substation Tuna is a strategic move. The reconstruction itself and the connection of the reconstructed substation to the 400 kV transmission line will give the regions of Stockholm and Uppsala an impressive power boost of 320 MW.

In collaboration with Siemens Energy AB as the main contractor responsible for complete design, Elnos is an important part of a substation reconstruction.

Undergoing a substantial transformation, the substation Tuna assumes a much larger role. Before the reconstruction, the substation featured three 400 kV and four 220 kV bays. Upon completion, it will incorporate three new 400 kV bays, one new 220 kV bay, and an entirely new protection and control system.

Within this project, our teams have been entrusted with the entire electrical assembly works in three new 400 kV bays, as well as with the replacement of secondary equipment in existing 400 kV bays. The construction of a new 220 kV bay and the replacement of secondary equipment in one of the existing 220 kV bays are also under our jurisdiction.

There is more.  Assembly and connection of secondary equipment in one old and one new 220 kV bay are in our hands too. The scope of work is, however, expected to expand to the remaining three 220 kV bays of this substation. At the same time, our teams are also to execute both secondary and primary connections of the new power transformer, the replacement of secondary equipment on the existing power transformer, and the connection of high primary circuits within the substation. On top of all these tasks, our experts are also entrusted with the general installations within the new control building of the substation.