The Keilaniemi substation serves the Helsinki region Metro and the Keilaniemi area. Its architecture, with its round shape and ornate façade, communicates the site's characteristics and the substation's function to the surrounding area.
The building's circular shape is based on its location in the middle of the surrounding busy traffic routes and dense development. The building opens out equally in all directions. The cylinder is cut asymmetrically, and this shape has made it possible to place solar panels on the roof at the desired angle and direction as a low structure.
Unusually for a substation building, the transformer and equipment rooms are stacked on top of each other on two floors.
The façade cladding is of form-bent, perforated stainless steel sheet. The decorative pattern on the facades was made by punching holes of different sizes in the straight sheets using a punching robot programmed with an ornamental pattern. Viewed from a distance, the small holes on the facade form a larger pattern that repeats around the building. The pattern is based on a photograph by the Dutch photographer Marc van Agteren, showing a tall transmission line pylon shot from the bottom up through the centre of the pylon.
The black solar panels on the roof of the substation were specially commissioned and their shape is adapted to the circular shape of the building at the edges. Half of the energy they produce is used in the substation itself, for example for lighting, and the rest is used to compensate for power losses in the transformer.
