Kvitåi power plant

The Kvitåi power plant is a hydropower plant on the Skiensvassdraget river in Tinn municipality in Vestfold and Telemark county, Norway.

History

Småkraft AS was initially given a rejection for the project. This was largely based on the argument that the power plant would have a negative effect on ice formation downstream, from where the station stands, due to a higher temperature in the water passing through the power plant. This would thus have a negative effect on ice climbing in the area. The case went to the OED, which determined that a halt in production during the winter months as a mitigating measure for ice formation could enable continued ice climbing activities, and thus the rejection was turned into a positive decision. The power plant now produces renewable electricity for the benefit of society and the environment, but it halts production between 15 December and 31 March to allow for ice climbing activities in the area.

The project

The detailed development plan was approved by NVE in late October 2017, which meant that construction work could begin in November. The development went relatively smoothly due to considerable efforts by the contractors, and it progressed until the autumn of 2018. At this point, it appeared that the generator would be delayed a few months. The project was in danger of being delayed until May 2019, as it would be impossible to transport the generator up to the station if there was too much snow. Fortunately, the weather gods were on our side and the snow stayed away until the generator was put in place and the project could move forward.

Technical information

The power plant has an inflow from a catchment area of 14.5 km2. Minimum water flow is 85 l/s in summer and 15 l/s in winter. The intake at elevation 927.5, and the station at elevation 660 gives a fall height of 267.5 metres. Power production is an estimated 6.08 GWh in a normal year. This corresponds with electricity consumption for approx. 300 households.

The Pelton turbine has a maximum flow rate of 1.22 m3/s and runs a 2845 kVA, 6600 V generator. The penstock is made of both GRP and GJS, and has a length of 1320 metres and a diameter of 600 mm. Voltage is converted up to 22 kV and delivered to the grid.

Technical data

Rainfall field

14.5 km²

Minimum water flow

Summer: 85 l/s

Intake elevation

928 m

Power station elevation

660,0 m

Drop height

267 m

Production

6,1 GWh
This corresponds to electricity 381 households.