Harsprånget – the largest hydro power station in Sweden
Initial development and delays
Harsprånget Power Station is located on the Lule Älv River approximately 8 km downstream of Porjus. With its proximity to the iron ore district, it was natural that the Harsprånget falls were chosen for electricity generation at an early stage. As a result of the industrial expansion and the increased demand for electricity, development of a 105 MW power station at Harsprånget was started in 1919. However, the severe economic crisis following World War One reduced the demand for electricity and construction was discontinued in May 1922.
Constructing Harsprånget Hydro Power Station
Some 20 years later, in 1945, construction resumed. Harsprånget was given a completely new layout 2 km further downstream. The power plant’s first unit was commissioned in 1951. When construction work on all three units finished in 1952, the installed capacity was three times greater than initially planned. To manage communication and transport to the building site, a railway and road were constructed from Porjus. Due to the isolated location, a complete town with necessary services had to be built. It consisted of houses for 1,200 employees and their families, shops, a hospital, a police station and leisure facilities. It was a construction camp on a large scale with high standards, making it a landmark in Swedish hydro power construction.
Supplying Sweden with electricity
When commissioned, Harsprånget generated more than one fifth of Sweden’s total electricity. Building a large hydro power station in the far north of Sweden, far away from many electricity consumers, created a need to build new power lines for transmission of the electricity southwards from the Lule Älv River. The solution was to build a new high-voltage transmission line from Harsprånget to Hallsberg (the Harsprång line). The transmission line is almost 1,000 km long, became operational in 1952 and was the world’s first transmission line for 400 kV.
Harsprånget initially consisted of three units with a total capacity of 330 MW. In 1974, construction of two additional units started which were commissioned in 1978 and 1980 respectively. Again, the capacity increased nearly three times, finally amounting to 945 MW. Today, Harsprånget has a generating capacity of 977 MW, which makes it Sweden's largest hydro plant by capacity. After the Stornorrfors facility, Harsprånget also generates the most electricity of Sweden’s hydro plants.
In recent years, Harsprånget has been upgraded to meet the demands created by the ‘10,000 year flood’, which is an event expected once every 10,000 years that causes extreme flood levels. Both the dam and spillways have been strengthened as part of this upgrade for precautionary purposes.
Characteristics about the Lule Älv River
Hydro power is a reliable, safe and renewable source of energy. Today, hydro power accounts for nearly half of Sweden’s total electricity demand. The Lule Älv River, by which Harsprånget is located, is Vattenfall’s and Sweden’s most important river for hydro power generation.