In October 2024, Sogn og Fjordane Energi (SFE) decided to rehabilitate the Øksenelvane plant in Bremanger municipality, Vestland county. The refurbishment of the 1953 facility represents the largest investment in SFE’s history and will, among other things, quadruple the installed capacity through the construction of an entirely new underground powerhouse.
Since 2023, Norconsult has been involved in the plant’s design and in preparing tender documents for the civil, electrical and mechanical contracts. The Company has also carried out waterway dynamics analyses and designed the facility to deliver system services in line with Statnett’s regulatory framework. Following an evaluation of bids during the summer of 2024, SFE selected suppliers for each contract. In the autumn of 2024, Norconsult contributed to a collaboration phase with the chosen turbine supplier, optimising the layout of the powerhouse.
The existing Øksenelvane plant will be replaced due to ageing electromechanical equipment, alkali–silica reaction issues in the powerhouse, and an operating profile that no longer meets the requirements of today’s power market.
The new facility will utilise the existing intake reservoir and regulation limits. Installed capacity will increase from 28 MW to 110 MW, distributed across two vertical Pelton turbines. The powerhouse will be located in a cavern half a kilometre inside the mountain, with a two-kilometre headrace tunnel and a tailrace tunnel leading out in to the fjord.
“At Norconsult, we are excited to contribute to making the development of the new Øksenelvane Hydropower Plant a success. This is one of several similar projects we have helped develop in recent years – and the first to move into the construction phase. The main objective is to increase capacity so that more power can be delivered when demand is at it’s peak, while also providing system services to help balance the grid. Both are critical to ensuring a stable and resilient power network for the future,” says Håkon Bergsodden, EVP for Renewable Energy at Norconsult.
“Designing a facility capable of delivering modern system services in line with Statnett’s updated requirements presents new challenges in the design process. Norconsult has the necessary expertise in this field and has developed calculation methods that verify compliance with Statnett’s functional requirements for the various types of system services,” Bergsodden adds.
Construction commenced in August 2025, and the plant is scheduled to be commissioned in the autumn of 2028.
For further information, please contact:
Henrik Charlesen, Senior Communication Advisor, Henrik.Charlesen@norconsult.com
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About Norconsult:
Norconsult is a leading pan-Nordic interdisciplinary consulting firm combining engineering, architecture and digital expertise across projects of all sizes, for private and public sector customers in infrastructure, energy and industry, buildings and architecture. Headquartered in Sandvika, Norway, Norconsult’s delivery model is centred around knowledge hubs and local presence through approximately 6,600 employees across more than 140 offices in Norway, Sweden, Denmark, Iceland, Poland and Finland.