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Porjus hydro power plant – a central point in Sweden’s industrial development

Porjus hydro power station
Porjus power plant is situated by the Stora Lule Älv River in Jokkmokk Municipality, northern Sweden, close to the Arctic Circle. When Porjus was built in the early 1900s its purpose was to transfer electricity to the Malmbanan railway line used for iron ore transport. The new hydro power plant and electrical wiring contributed to high growth in the Swedish mining industry. At present, Porjus power plant is the third-largest in Sweden. Porjus is also the last stop before you enter the Laponian Area, a UNESCO World Heritage area which includes four national parks.

Characteristics of hydro power and 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 Porjus is located, is Vattenfall’s and Sweden’s most important river for hydro power generation. The first stage of development of the Lule Älv River took place in 1910–1915, with the start of the construction of Porjus Power Station. The youngest power station in the Lule Älv River, located near the small village of Ritsem, was completed in 1977. In total, the Lule Älv River has 16 power stations situated from the Norwegian border down to the Bay of Bothnia.

In the future, hydro power will continue to play an important role as a renewable energy source. Major investment programmes are under way in Vattenfall’s hydro power plants to increase capacity and strengthen the dams, which aims to generate more electricity as well as improve safety.

Modernisations and development units

A new power station with two new units was built in the mid-1970s (1971–1975). The new power plant has a total output of 465 MW, which is more than 10 times that of the old one.

All new transformers were constructed underground and a new building was therefore not needed. However, the old building remains, as a magnificent monument and visitors’ centre. The old dam has also been replaced by a rockfill dam with an impervious core of moraine. It has been erected immediately downstream of the old dam and is provided with two new spillways, closed by tainter gates.


History – hydro power was an important factor in the industrial expansion and development of Sweden

Hydro power was utilised as early as in the 13th century. Gristmills and sawmills were built, logs were floated downstream and the rivers became vital for transport. But their most important contribution to the development of society had yet to be realised.

With the late industrial revolution came large-scale use of electricity. For centuries, only a tiny fraction of the kinetic energy from the rivers had been utilised. Then, at the turn of the last century, engineers began to see the enormous potential of hydro power. In 1910, Sweden’s first hydro power plant, Olidan, on the Göta Älv River, began to supply power to industry and the railways. That signalled the start of the development of the Lule Älv River and Porjus Hydro Power Plant. Until then, society had been very sceptical of electricity, but when the problem of transporting electricity over long distances without power loss was solved, electricity gained support.

The construction of the power plant started in 1910, without any roads or railway to Porjus. Both the construction of, and the transport of supplies for, the building were extremely arduous, because materials and supplies had to be carried 50 kilometres from the nearest town, Gällivare. Five tonnes of materials and supplies were carried on planked tracks over the no-road wilderness to Porjus during the first few months. However, this extraordinarily heavy and time-consuming work was facilitated in 1911 thanks to completion of the ore railway from Gällivare to Porjus.

In 1915 King Gustaf V inaugurated Porjus Hydro Power Plant by telephone, because his advisers thought that it would be unsafe to undertake such a long journey in the midst of the war. Porjus became quickly a central point in an industrial Sweden that was consuming increasing amounts of energy. When the power plant was inaugurated, there were already 20 hydro power stations around the country, but Porjus attracted much attention due to its geographic location and its construction technology that was very advanced for its day. The power station is located underground, on a site blasted out of the rock. The number of turbines in the old power plant expanded between 1920 and 1960 to nine units. The turbines still work, but are not used daily; they can instead be used as test sites for new equipment.