Ulla-Førre
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
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).