Start of Construction
The newly commissioned 95MW Budarhals hydroelectric power plant (HEPP) on the Tungnaá River in Iceland is the seventh biggest power plant to be owned and operated by state-owned power company Landsvirkjun.
The hydropower station was connected to the national grid in January 2014 and started commercial operation in March 2014. It is expected to increase the total installed hydro capacity of the Nordic island country to 1,980MW.
The Budarhals hydropower project was launched in 2001, but its construction was halted for a long time due to lack of financing. Construction works resumed in 2011, with the help of $70m loan facility from Nordic Investment Bank.
The Budarhals plant is expected to generate about 585Gwh of electricity annually. The generated electricity will be used for aluminium production as well as a silicon metal plant near Husavik.
Budarhals HEPP location and details
The hydroelectric power plant is situated within the Þjórsá and Tungnaá River water catchment area near the meeting point of the Kaldakvísl and Tungnaá rivers. It utilises the tail water of the Hrauneyjafoss power station located upstream as well as the Kaldakvísl River water.
The project comprises of two 25m-tall dams with a combined length of 1,400m. One dam is built across the Kaldakvísl River while the other is built across the outflow from the Hrauneyjafoss power facility. The dams create a reservoir called Sporðalda which is 2,300m-long and has a storage capacity of 335million cubic metres.
A 4km long headrace tunnel sends water from the reservoir to the intake facility of the plant from where the water is released through two 60m-long steel pressure pipes to drive the turbines of the powerhouse. The power plant comprises of two 47.5MW vertical axis Kaplan turbines with a gross head of 40m.
Power transmission from the Budarhals power plant
The power generated at the Budarhals plant is fed into the national grid via the 5.6km-long, 220kV overhead transmission line Budarhalslina 1 that connects the substation of the plant with the Hrauneyjarfosslina 1 transmission line at Langalda.
Budarhals HEPP construction
The initial construction works for the project involved the building of an access road and a bridge across the Tungnaá River, as well as the excavation for surge basin.
The dam filling and the filling of the Sporðalda Reservoir were completed in 2012. The powerhouse and intake structure were completed by the end of 2013.
Contractors involved with the Budarhals power plant development
The Budarhals power plant was designed by OG Architects. Mannvit supervised the geological and hydraulic research for the project in addition to carrying out the pre-design and feasibility study of the project and the tender design, documentation and review for the penstock and gate equipment.
Ístak was awarded the contract for the construction of civil structures including the tunnels, dams and powerhouse in October 2010. Voith supplied the electromechanical equipment including powerhouse cranes and station control systems. Alstom Hydro was awarded a contract in April 2012, to construct and install the gate equipment and penstocks.
Efacec, a Portuguese company, was awarded the contract to provide generator step up transformers. South Korea’s Iljin manufactured the power cables for the substation. Landsnet was responsible for the transmission infrastructure of the power plant.
Hydropower in Iceland
Iceland is one of the few countries producing all electricity from renewable sources. Hydropower comprises about 73% of its total electricity generation while the rest is produced from geothermal resources.
Iceland also boasts of producing the highest amount of green electricity per capita in the world.