Ulla-Førre

Ulla-Førre
The artificial lake Blåsjø and Storvassdammen
Country	Norway
Status	Operational
Owner(s)	Statkraft
Reservoir
Creates	Blåsjø
Total capacity	3.1 km3 (0.74 cu mi)
Surface area	84.48 km2 (32.62 sq mi)
Normal elevation	930–1,055 m (3,051–3,461 ft)
Kvilldal Hydroelectric Power Station
Installed capacity	1,240 MW
Annual generation	3516,52 GWh
Saurdal Hydroelectric Power Station
Installed capacity	640 MW
Annual generation	1,335 GWh
Hylen Hydroelectric Power Station
Installed capacity	160 MW
Annual generation	583 GWh
Stølsdal Hydroelectric Power Station
Installed capacity	17 MW
Annual generation	51 GWh

Ulla-Førre is a hydropower complex in Suldal, Hjelmeland and Bykle in Norway. It has an installed capacity of approximately 2,100 MW, and the annual average production is 4.45 TWh (16.0 PJ) (1987-2006), while its annual potential is about 7.8 TWh (28 PJ). The complex includes the artificial lake Blåsjø, which is made by dams around 1,000 metres (3,300 ft) above the sea level. The hydroelectric power station in the complex are Saurdal, Kvilldal, Hylen and Stølsdal, operated by Statkraft.

Blåsjø is the tenth largest lake in Norway by area. It is located in the municipality of Bykle in Aust-Agder county and the municipalities of Hjelmeland and Suldal in Rogaland county. The lake is about 20 kilometres (12 mi) west of the village of Bykle. It has a surface area of 84.48 square kilometres (32.62 sq mi). Its surface swings between 930 and 1,055 metres (3,051 and 3,461 ft) above sea level depending on seasonal weather and power consumption, and it has a shoreline of about 200 kilometres (120 mi). At the highest regulated water level, Blåsjø contains 3105 million cubic meters of water.

The Kvilldal Power Station is a located in the municipality of Suldal. The facility operates at an installed capacity of 1,240 MW, making it the largest power station in Norway in terms of capacity.Statnett plans to upgrade the western grid from 300 to 420 kV at a cost of 8 billion NOK, partly to accommodate the NSN Link cable from Kvilldal to England.

The Saurdal Power Station is a hydroelectric and pumped-storage power station located in the municipality of Suldal. The facility operates at an installed capacity of 674 MW (in 2015). The average energy absorbed by pumps per year is 1,189 GWh (4,280 TJ) (in 2009 to 2012). The average annual production is 1,335 GWh (4,810 TJ) (up to 2012).