Ístak hf., the Icelandic subsidiary of the Aarsleff Group, has signed a contract to expand the Sigalda hydropower plant in central Iceland under a project valued at approximately DKK375m (US$55m).
The project will increase the plant’s installed capacity from 150MW to 215MW through the addition of a new 65MW generating unit. According to project figures, the additional output is expected to provide electricity equivalent to the annual consumption of more than 50,000 households.
Construction work is scheduled to begin in late summer 2026, with completion expected in 2029.
The scope of works includes construction of new concrete structures to accommodate the new turbine and generator, expansion of the plant’s water intake system and upgrades to existing infrastructure.
Civil works will include excavation and foundation works around the existing power station, as well as installation of a steel penstock approximately 100m long to increase water supply to the facility.
Additional work includes expansion of the drainage channel, installation of slope and wave protection measures, upgrades to fire safety and ventilation systems, construction of a new water tank and extension of existing crane tracks.
The project is located about 160km east of Reykjavik and around 18km from another Landsvirkjun project currently being completed by Ístak.
Construction activities are expected to involve excavation of almost 32,000m³ of rock, installation of 660m of temporary sheet piling and placement of more than 10,000m³ of concrete.
Ístak said the project would draw on expertise from across the Aarsleff Group in delivering large energy and infrastructure projects. Landsvirkjun, Iceland’s state-owned power company, is the project owner.
