By Per Einar Faugli and Randi Bà¥rtvedt
The development of hydropower is the single most significant factor contributing to economic growth and material welfare in Norway. For more than 100 years, the country has enjoyed the highest per capita production of hydropower in the world.
When hydropower development first began, the technology was not available to transport electricity over long distances. As a result, power-intensive industries had to be located close to their power sources. Many industrial communities had their origins in this situation, including Odda and Tyssedal on the west coast of southern Norway.
Building Tysso I
Odda and Tyssedal are only 6 kilometers apart at the end of a fjord, and their history is closely linked. The river Tysso, in Tyssedal, was ideal for hydropower development, while the wide slopes in Odda were a prime location for a factory. Sun Gas Co. of Great Britain wanted to build a carbide factory in Odda, so engineer Sam Eyde, a central figure in the pioneering period of Norwegian industry, was approached in 1905. Power company Tyssefaldene Inc. was founded on April 20, 1906, and three weeks later parliament approved plans to develop the hydro plant, called Tysso I.
In many ways, Tysso I represents the origin of hydropower development in Norway. It ws the first hydro facility in Northern Europe to be built using the “modern” principles of a high fall supplying pressurized water to the plant via a tunnel or pipeline. Before Tysso I was built, hydro facilities in Norway were low-head (low pressure) arrangements using ow falls in the river.
Construction of Tysso I started in September 1906, and the first of four stages was completed in 1.5 years. This initial construction included the first part of the power station to house six turbine-generating units, two penstocks, a supply tunnel, a reduction tunnel in the reservoir, a temporary power station to supply the construction work, a harbor, ropeways and cable railways, employee housing, and a transmission line to Odda.
The tunnel that was built to carry the water from the reservoir to the distribution pool was an innovation because penstocks normally were used. The head from the distribution pool to the power station was 400 meters. Water was transported from the pool to the power station via penstocks.
Time was the primary reason for dividing the Tysso I construction into stages. The station had to be producing power by the time the carbide factory was completed. In addition, there were uncertainties as to how much hydropower could be supplied by the watercourse, how effective the power station would be, and if there would be customers for the electricity that could not be transmitted long distances.
Operating Tysso I
Electricity production at Tysso I began in 1908, using six 4.1 megavolt-amperes (mva) turbine-generating units to supply electricity for the new carbide factory. The following year, a cyanamide plant was completed, also owned by Sun Gas. During 1909, an additional 3.46-mw unit was installed at the Tysso I powerhouse, a second transmission line to Odda was built, and construction of the main dam, called Ringedal, commenced.
The building of Tysso I continued in stages. Stage II, from 1910 to 1912, involved installation of two 9.6-mw units and construction of penstocks 3 and 4. During Stage III in 1913, two more 9.6-mw units were added. Stage IV, which took place in 1914 and 1915, involved the addition of one 9.6-mw and two 11.2-mw units, as well as construction of penstock 5. To house these additional units, the power station was expanded. The penstock added in 1915 was the largest in the world at that time, with an upper diameter of 1,700 millimeters and a total weight of 700 tons.
When construction ended with the completion of Ringedal Dam in 1918, the 100-mw power plant had an output of 116.7 mva from 14 Pelton units. The station’s average annual production was 700,000 megawatt-hours.
When completed, Tysso I was Norway’s largest power plant and received considerable international attention. Ringedal Dam also was the largest in the country, at 520 meters long and 33 meters high. The dam, concrete clad with hand-carved granite, was found to be leaking and was repaired using a front-plate in 1929-1931. The technique developed at Ringedal has since been used to repair many gravity dams.
In the fall of 1980, one of the penstocks burst at Tysso I. An examination revealed that four of the five penstocks were dangerous to use, due to wear over the years, so they were taken out of service. Replacing the penstocks was prohibitively costly compared to what would be gained. Consequently, only Units 13 and 14 continued running, and in December 1989 power production was discontinued. The intention had always been to scale down production at Tysso I because the equipment did not give output compared to the effort of running the station. The loss of the penstocks accelerated the process.
Several power stations were built in Tyssedal between 1939 and 1980, and these make up for the production lost at Tysso I. Skjeggedal was built in 1939 to take advantage of the fall of water from Ringedal Dam to the Tysso I supply tunnels. Mà¥geli was built in 1956, and 180-mw Tysso II was completed in 1967. Finally, the 200-mw Oksla station was built in 1980. In 1986, Skjeggedal was turned into a pumping station, pumping water that was used at Mà¥geli up to Ringedal Dam so it can be re-used at Oksla. Construction of power stations in Tyssedal continues, with 5.5-mw Upper Bersà¥vatn and 4-mw Lower Bersà¥vatn opening on May 14, 2005. These stations exploit the height difference between existing reservoirs. Restrictions on hydropower development are now very strict, so expanding production at existing plants is very important.
Hydropower’s contribution to Norway’s development
The textile industry initiated the industralization of Norway in the 1840s. It was a great advantage that the textile industry could be based on hydropower rather than steam power as in England. The industry that developed after 1905 demanded far more energy than before.
From around 1900, the country’s industrialization was based on the growth of new science and technology. This involved the invention and development of new industrial processes, in which electricity was used to refine raw materials and make new production methods possible. The electrometallurgical and electrochemical industries were the main hydropower consumers and became Norway’s backbone. In addition to the carbide factory, the power supply from Tysso I was used for Cyanamid, zinc, and aluminium factories. The plant also supplied electricity to the communities surrounding these factories.
Construction of the first stage of the 100-mw Tysso I plant was completed in 1908. A penstock added in 1915 was the largest in the world at that time.
Foreign investment was pivotal for hydropower development in Tyssedal. The massive foreign purchase of the Tysso watercourse (most of the funding for the foundation of power company Tyssefaldene came from abroad) led to the so-called “Panic Act” of 1906, which was the basis for the Norwegian concession laws. These laws state that foreigners cannot purchase land or water rights without a concession. A typical prerequisite was that ownership would be turned over to the Norwegian state after 60 to 80 years.
Tysso I also played a significant role in watercourse protection. With its glacier, waterfalls, fjord, and mountains, Odda had a thriving tourist industry before Tysso I was developed. Nearly 50 percent of all foreign visitors to Norway came to Odda, and the Ringedalsfoss and Tyssestrengene waterfalls in Tyssedal were especially popular. Tyssefaldene acquired the rights to these waterfalls in 1920, frightening environmentalists. As a result, the 275-meter-high Vettisfossen waterfall became protected in 1924, leading to extensive work to protect waterfalls and watercourses. Among these is the watercourse in Odda, which was threatened by hydropower development in the 1960s. This initial work matured in the 1960s into the Norwegian Protection Plan for River Systems, which was completed in 1973. As of 2007, 387 rivers are included in the plan.
Protecting Tysso I
The Tysso I power station has great aesthetic value and is considered among the best of Norway’s 20th century architecture. The design draws heavily on cathedral architecture, with the machine hall closely resembling a cathedral space. The high windows and clerestory flood the hall with daylight. The control room has taken on the role of gallery. The quality of the building, the location in the fjord and waterfall landscape, and the surrounding industrial community make the Tysso I power plant unique as cultural heritage.
Wedged between two national parks and a virtual stone’s throw from a protected watercourse, the power plant offers a unique experience. In 2000, the plant was declared protected by royal resolution and is protected by the Directorate of Cultural Heritage. Restored inside and out, the plant was officially opened on May 14, 2005, as a museum. Tysso I is now the only protected power plant in Norway, preserved in original condition. Work is under way to ensure this plant a place on the world heritage list of the United Nations Educational, Scientific and Cultural Organization (UNESCO). s
Mr. Faugli may be reached at NVE, Middlethuns gt. 29, Box 5091 Maj, N-0301 Oslo, Norway; (47) 22-959595; E-mail: email@example.com. Mrs. Bà¥rtvedt may be reached at NVIM, Naustbakken 7, 5774 Tyssedal, Norway; (47) 53-650050; E-mail: firstname.lastname@example.org.
Tone Hesjedal with the Norwegian Museum of Hydropower and Industry translated this article, as well as coordinating the contributions of Mr. Faugli and Mrs. Bà¥rtvedt.
Per Einar Faugli is senior advisor with the Norwegian Water Resources and Energy Directorate. Randi Bà¥rtvedt is director of the Norwegian Museum of Hydropower and Industry.