Statkraft has applied for a licence to install a third generating unit at the Alta hydropower plant in northern Norway, targeting an annual production increase of 100–150 GWh through improved utilisation of seasonal floodwater currently bypassed through spill tunnels.
The project would make use of infrastructure already designed to accommodate a third unit, including the dam, tunnels and underground machine hall. The proposed work is limited primarily to installation of a turbine, generator and transformer within the existing cavern, avoiding major excavation works or new spoil disposal areas.
Alta hydropower plant, commissioned in the 1980s, operates with a 185m head from the 18km-long Virdnejávri reservoir and currently has two generating units. During periods of high inflow in spring, summer and autumn, excess water is discharged through flood tunnels downstream of the dam. Under the proposal, a larger share of this water would be routed through the power station before release.
Statkraft said the project would not require changes to existing manoeuvring regulations governing reservoir operation, nor alter flow conditions in the salmon-bearing reaches of the Alta River downstream of the plant. Reduced flow would occur only along an approximately 1.8 km non-salmon-bearing reach between the flood tunnel outlet and the station tailrace.
The Norwegian Water Resources and Energy Directorate (NVE) has opened the licence application and environmental impact assessment for public consultation. According to Statkraft, the earliest possible commissioning date is 2030, subject to regulatory approval and a final investment decision.
The proposal has received unanimous backing from Alta municipal council, which voted in favour of the additional unit on 24 February 2026. Public information meetings have also been held in Alta and Masi/Mazé as part of the consultation process.
