Lauttasaari substation serves the local power grid. Due to its central location, the cooling system for the substation's transformers was designed to be as quiet and energy-efficient as possible.

The transformer buildings are made of high-quality in-situ self-compacting concrete bleached with titanium oxide. The outer walls of the switchgear building consist of load-bearing inner shell elements, rigid thermal insulation and an in-situ outer shell as the façade surface. Each casting section of the walls was made without a working seam in a 9 m high casting. Rust-coloured weathering steel grilles complement the concrete structures. The colour and texture of the grille contrast with the smooth, solid concrete surfaces.