The power plant was commissioned in 1979 and utilises a 240-metre waterfall between the lakes Svartevatn and Gravatn.

Svartevatn lake, which is an intake reservoir, is dammed up by a 130-metre high rock-fill dam. This is the largest dam in the Sira-Kvina development. The lake can be regulated between 899 and 780 metres above sea level, and the reservoir can contain up to 1,400 million cubic metres of water.

Two vertical Francis turbines are installed with a total output of 200 MW. The turbines are unique in that they are reversible pump turbines that can pump water back into the reservoir through the 1,200-metre tailrace tunnel to store it for later production. This is done during periods with low power prices and good reservoir filling, usually in the spring and autumn.

With the construction of Duge Power Plant, the fourth building stage of the Sira-Kvina development was complete, and the waterfalls in the Sira watercourse could be fully utilised from a height of 900-metres all the way down to the sea.

Owners: Lyse Produksjon AS 41.1%, Statkraft 32.1%, Skagerak Kraft AS 14.6%, Agder Energi AS 12.2%.