As the main contractor for TEV, AF has constructed a new underground power station to replace the existing Øvre og Nedre Leirfossen power station.
The station was officially opened on 2 October 2008 and will result in an increase in power generation of 43 GWh, equivalent to the annual consumption of around 2000 homes. The power station will produce a total of 193 GWh, enough for around 8600 households.
AF Anlegg Olje & Gass was responsible for rock and concrete works in connection with the expansion and carried out extensive work inside the rock. In addition, AF was responsible for administering the technical and structural aspects of construction. AF started in spring 2006 by blasting tunnels and the rock cavity. Since then, AF has contributed to building a state-of-the-art power station on several levels, including an extensive tunnel system.
A new intake was built, via which the water is fed into a 30 m vertical shaft and a tunnel down to the power station. A new discharge tunnel from the power station was built, via which the water is fed out into the river again. A total of around 2.8 km of tunnels were blasted out, producing approximately 165,000 m3 (solid) rock, equivalent to approximately 25,000 truck loads. A total of approximately 8500 m3 concrete was poured on site.
