Vassvikelva power plant

Vassvikelva power plant is located by Vassvikvatnet lake and Vintertun in Ullensvang municipality in Vestland county. The dam and intake consist of a blasted pool in the mountain with a 3-metre high and 15-metre wide threshold. The intake construction is made of steel. The waterway has a total length of about 900 metres, which has buried pipes along the entire stretch. The station will be built in the standard Småkraft style.

History

The Vassvik Farm is located at Vintertun in Odda municipality. The farm also own the falls in Stølselva down to Vassvikevatnet. Landowners were aware that the river might have the potential for small-scale power. Realisation of the value creation from the river was the subject of several plans over the years.

In 2007, a contract was signed with Småkraft, which assumed the risk, the work with the licensing process and the development itself. NVE granted a licence in 2012. Excavators arrived in 2013, and in the autumn of 2014, the power plant was completed. The area was also given a new and upgraded grid, to which the Vassvik power plant can now deliver its power.

With its natural stone walls and a glass façade, the station building has an attractive exterior and has been nicely adapted to the terrain facing Vassvikevatnet lake.

The project

The implementation of the project has had its challenges, including archaeological excavations, a steep terrain, a costly and lengthy access to the power and telecommunications network, as well as a tough winter during the construction phase – just to name a few.
Their contributions in the form of local knowledge, and their presence during the construction phases have enabled a smooth project implementation .

Technical information

The Vassvik power plant has inflow from a catchment area of 6.3 km2. Minimum water flow in winter is 30 l/s, while in the summer it is 100 l/s. Intake at elevation 689 and power plant at elevation 420 gives a fall height of 269 metres. Power production is an estimated 7.7 GWh in a normal year. This corresponds to an electricity consumption for 385 households.

Its Pelton turbine has 5 nozzles with a maximum flow rate of 1.200 l/s, and runs a 3100 kVA, 6600 v generator. All power is converted up to 22 kV and delivered to the grid.
The intake dam is built with a concrete threshold to create an intake basin. The intake construction itself is Småkraft’s own prefabricated “shark cage”. The intake is well-adapted to the terrain at the site and appears to be a modest intervention.

The penstock is made of GRP/cast iron and is buried between the intake and the station. Its length is 896 m with a diameter of 700 mm.

The 80 m2 power station building is constructed in the familiar Småkraft design and well integrated into the terrain. Outflow is led through a pipe/channel out into Vassvikevatnet lake.

Technical data

Rainfall field

6.1 km²

Minimum water flow

Summer: 100 l/s

Intake elevation

686 m

Power station elevation

420,0 m

Drop height

266 m

Production

7,7 GWh
This corresponds to electricity 481 households.