Hydro bought hydro rights in the river system in the 1950s with a view to produce electricity for a future aluminium plant.
Main construction took place from 1963 to 1968, with up to 1,250 workers employed at a time, building out Suldal I, Røldal, Suldal II, Novle and Kvanndal. The power stations at Svandalsflona and Middyr were added later.
As Suldal and Røldal were built, construction was ongoing at Hydro’s aluminium plant at Karmøy on the west coast.
Electricity was transported on dedicated power lines to Karmøy. Hydro owns 95.2 percent of the power plants at Røldal and Suldal; Statkraft owns the rest. The companies use power from plants based on the same ratio.
Facts about the power plants and stations
The power plants at Røldal and Suldal have a catchment area of 793 square kilometers and a reservoir capacity of 833 million cubic meters. The largest reservoir is Lake Valldal near Hardangervidda National Park.
There are seven power stations. Their capacity and production is shown in the table below. With a turbine placed 1,240 meters above sea level, Middyr Power Station is the highest power station in the area. The lowest are Suldal I and Suldal II, both 68 meters above sea level.
Middyr
Hydro's share: 95.2%
Installed capacity: 1.3 MW
Average production: 4 GWh/year*
Svandalsflona
Hydro's share: 95.2%
Installed capacity: 20 MW
Average production: 34 GWh/year*
Novle
Hydro's share: 95.2%
Installed capacity: 49 MW
Average production: 197 GWh/year*
Røldal
Hydro's share: 95.2%
Installed capacity: 161 MW
Average production: 773 GWh/year*
Suldal I
Hydro's share: 95.2%
Installed capacity: 161 MW
Average production: 911 GWh/year*
Suldal II
Hydro's share: 95.2%
Installed capacity: 151 MW
Average production:657 GWh/year*
Kvanndal
Hydro's share: 95.2%
Installed capacity: 41 MW
Average production: 159 GWh/year*
* Hydro's share
