Cowi wins hydropower station expansion in Iceland

Sigalda Hydropower plant expansion began earlier this year (Photo: Cowi)

The project began in early 2025 and is scheduled for completion in late 2028.

The new hydropower project, along with the 95 MW Hvammsvirkjun, which Cowi is also designing, will aid the country’s green transition by meeting the rising household demand for energy.

Cowi’s work on the project encompasses the entire engineering design for the expansion. This includes tasks such as tender design, preparation of construction documents, design reviews, as well as risk and cost analyses.

Additionally, Cowi says that it will handle the design, integration, and coordination with the ongoing renovation work at the existing plant.

“With the expansion of Sigalda Hydropower Station we are helping Landsvirkjun secure sustainable power for the citizens and businesses in Iceland. In recent years, we have witnessed challenges in new power supply which has affected business growth. We are confident that COWI’s experts can play a role to address this issue for the benefit of society at large,” says Gunnar Sverrir Gunnarsson, managing director at Cowi Iceland.

“Once completed, the 215 MW plant will add increased flexibility in energy supply and enable Landsvirkjun to better meet peak demand. By making better use of the increased water flow, Landsvirkjun is fulfilling its role of maximising the yield of the energy resources entrusted to the company, with sustainable utilisation, value creation and efficiency as guiding principles,” adds Eysteinn Einarsson, project manager at Landsvirkjun.

The 150 MW hydropower station has been in operation since 1978, producing 920 GWh annually. Its infrastructure includes the Sigalda Dam, the 14 km² Krókslón reservoir, and a 550-metre tailrace canal that connects it to the Hrauneyjafoss hydropower station.