Mr Bjarni Benediktsson, Minister of Finance and Economic Affairs and Ms Ragnheiður Elín Árnadóttir, Minister of Industry and Commerce officially started up the turbines of the Búðarháls Hydropower Station, in the presence of the media, last Friday.
The Búðarháls Hydropower Station, the newest hydropower station in Iceland, was officially started up by Mr Bjarni Benediktsson, Minister of Finance and Economic Affairs and Ms Ragnheiður Elín Árnadóttir, Minister of Industry and Commerce at an official start- up ceremony on the 7th of March, 2014. The Búðarháls Hydropower Station was formally given its name at the conclusion of construction and the beginning of operations. It is the latest addition to Landsvirkjun’s (and therefore Iceland’s) fleet of hydropower stations.
The Búðarháls Hydropower Station is located within the Þjórsá- and Tungnaá River water catchment area and will be operated alongside Landsvirkjun’s other stations in the area. The Station is the 7th largest power station owned by Landsvirkjun. The installed capacity of the Station is 95 MW and it generates approximately 585 GWh of electricity per year for the national grid.
Hörður Arnarson, CEO of Landsvirkjun made the following statement:
“The development and construction of the Búðarháls Hydropower Station has been exemplary by any standard and cooperation on the project has been a unified effort. Landsvirkjun is very proud of this achievement. Búðarháls will be Landsvirkjun’s 16th power station, producing green, sustainable energy for the national grid and creating value for our owners, Icelandic society, for years to come.”
Búðarháls marks a turning point in the development of hydropower stations in the Þjórsá and Tungnaá water catchment area as the Station utilises the 40 metre head in the Tungnaá River from the tail water of the Hrauneyjafoss Power Station to the Sultartangi Reservoir. The head from Þórisvatn and beyond Búrfell is therefore now fully utilised; the head is 450 metres in total.
The Búðarháls reservoir has been given the name Sporðalda and is formed by two dams. One of the dams was built across the Kaldakvísl River and the other across the tailwater from the Hrauneyjafoss Power Station. A 4km tunnel channels the water from the reservoir, underneath the Búðarháls ridge, to the intake.
At the height of construction work, nearly 400 employees were involved in the construction of the Búðarháls Hydropower Station. The measured labour force was approx. 900 man-years and 2 million working hours and work was often carried out under challenging and difficult conditions.
Safety issues were at the forefront of construction work carried out for the Búðarháls Hydropower Station; both by Landsvirkjun and its main contractors. The aim was to maintain an accident free site; a “zero” accident policy. There was a strong focus on safety issues throughout the construction period and the success rate was high. There were no serious incidents and only a few minor incidents were recorded.
More than 100 years have passed since the first plans were introduced to utilise the Þjórsá and Tungnaá water catchment area. There were immediate proposals for the utilisation of Hrauneyjar and Búrfell alongside plans for the utilisation of the lower end of Þjórsá.
The first proposal for the utilisation of Búrfell was put forward in 1960 with plans for a powerhouse and a dam to the east of the ridge. During this period, the project was referred to as the utilisation of the Tungnaá River by Langalda. The idea to channel the Tungnaá River through the ridge was introduced by the National Energy Authority in 1971.
The Landsvirkjun Board of Directors made the decision to build the Búðarháls Hydropower Station in 2001, the same year that the Prime Minister's Office gave Landsvirkjun permission to utilise the water rights, quarries and other ground materials in the area for the development of the site. The Minister of Industry issued the permit for Búðarháls in August, 2001 and operating licenses were issued by the Municipalities of Ásahreppur, Djúparhreppur and Holta and Landsveitir in August and September of the same year. Construction began at the end of 2001 but was later delayed.
Construction was expected to begin again in 2009 but was delayed as a result of the uncertainty surrounding the Icelandic economy. The financial markets were unstable and financing the project proved challenging. A decision was made to continue with the project in the spring of 2010 and the first tenders were advertised in June of that same year. Financing the project proved to be easier than anticipated and the fact that Landsvirkjun was successful in securing long-term finance attracted some attention, considering the lack of liquidity in the European markets.
Four years have passed since the first tenders were released and the hydropower station is now operational and is testimony to the extensive and demanding work completed on the project. Construction work was mostly completed by the end of last year. Generating unit 1 was subject to a 28 day testing period at the beginning of January and unit 2 in the beginning of February.
The design of the Búðarháls Hydroelectric Power Station was completed in cooperation with a number of Icelandic engineering consultants. Efla hf provided the civil and structural tender design for all components and was responsible for the project management of other design work. Mannvit hf designed the penstocks and gate equipment and Verkís hf designed the mechanical equipment and in-house systems. The architectural design of Búðarháls was undertaken by the architects Ormar Þór Guðmundsson, Garðar Guðnason and Sigurður Gústafsson, working on behalf of the firm OG Architects in cooperation with the engineering consultants at Hnit.
Two dams were built at the Búðarháls Hydroelectric Power Station, to the east of Búðarháls ridge and a short distance above the junction with the Tungnaá River and the Kaldakvísl River. One of the dams was built across the Kaldakvísl River and the other across the tailwater from the Hrauneyjafoss Power Station. The dams are both approximately 25 metres at their highest point and have a combined total length of 1400 metres. The two dams form the intake reservoir (the Sporðalda Reservoir) for the Búðarháls Hydropower Station; the reservoir’s total surface area is approx. 7km2. A headrace tunnel, approximately 4 km in length, channels the water from the intake structure at the Sporðalda Reservoir, westward under Búðarháls ridge, to a surge basin by the Sultartangi Reservoir. Two steel penstocks transport the water from the intake to the station’s turbines. The powerhouse is mostly above ground, built into the western side of the slope of Búðarháls ridge.There are two generating units, each with an installed capacity of approx. 48MW.
Construction work for the Búðarháls Hydropower Station originally began at the end of 2001. The initial development of the area included the construction of a bridge across the Tungnaá River and an access road, laid across Búðarháls, up to the construction site for the powerhouse and the Sporðalda Dam. Excavation also began for the surge basin. In the summer of 2008 and 2009 more preparatory work was carried out including the laying of a power cable from the Hrauneyjafoss Power Station to the proposed construction site. Work camps were also erected.
The first tenders were advertised in June, 2010. An agreement was reached with the construction company Ístak with regard to the construction of the tunnels, dams, powerhouse and other structures in connection with the development. In December, 2010, an agreement was reached with the German company Voith-Hydro to supply all machinery and electrical equipment for the power station. Tenders for other parts of the project were completed by 2012. A contract was signed with IAV Construction, with regard to the construction and installation of penstocks in September, 2011.
A contract was signed with the French company Alstrom Hydro, with regard to the construction and installation of gate equipment and penstocks in January, 2012. A contract was also signed with the Portuguese company Efacec, with regard to the production of generator step up transformers in April of that same year. All tenders were advertised in the European Economic Area. The company Iljin in South Korea manufactured the power cables for the Landsnet substation. Many other sub-contractors, both national and international, took part in the project.
The single largest project phase undertaken in the development of the Búðarháls Hydropower Station was the construction of the headrace tunnel under the Búðarháls ridge. The underground headrace tunnel is approx. 4 km in length and the total cross section area is 140 m2. The tunnel was excavated from both ends and in two phases, as a result of its height. Excavation work was completed in September of this year and water was released into the tunnel in November. The geological conditions were more challenging than originally anticipated and consequently the completion of tunnelling work was 60 days behind schedule.
Dam filling began in the summer of 2012 and was completed by the autumn. The filling of the Sporðalda Reservoir began in November and was completed within three weeks.
Construction work on the powerhouse and intake structure was completed in 2012 and 2013 was spent finishing the interior and on various in- house systems. Work on the powerhouse and intake structure was fully completed by the end of 2013.
Work camps and contractor’s equipment is expected to be moved from the area in the near future. The summer will be spent completing work on the clean-up and landscaping of the areas around the station’s structures.