Ulla-Førre

Ulla-Førre is a hydropower complex in Southern Norway. It is situated along the borders of Suldal Municipality and Hjelmeland Municipality (in Rogaland county) and Bykle Municipality (in Agder county), Norway. It has an installed capacity of approximately , and the annual average production is (1987–2006), while its reservoir capacity is about ; at full production, it can last seven to eight months. The complex includes the artificial lake Blåsjø, which is made by dams around above the sea level. The hydroelectric power stations 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 on the border of Bykle Municipality in Agder county and Hjelmeland Municipality and Suldal Municipality in Rogaland county. The lake is about west of the village of Bykle. It has a surface area of . Its surface swings between above sea level depending on seasonal weather and power consumption, and it has a shoreline of about . At the highest regulated water level, Blåsjø contains of water.