With an installed capacity of 104 MW, pumped-storage power plant Hintermuhr in Lungau is the largest one operated by Salzburg AG. It was initially put into operation in 1991 and fitted with a pump   turbine in 2008.

25 years after its commissioning, the facility has now undergone an extensive overall revision. The package of measures was focussed mainly on the revision of machine unit 1 and corresponding equipment. At the same time, the automation system was brought up to the latest technical standards. In total, Salzburg AG invested around six months of revision work.  Emphasising the significance of this project for Salzburg AG,  Leonhard Schitter said, “Hintermuhr is celebrating its 25th  anniversary this year. Now that machine unit 1 has been fully  refurbished, one of our largest facilities is back up to the latest technical standards and ready to supply energy to around 43,000 households.”