The new Boen Foss small-scale hydropower plant construction project is well underway. It is located within the border of Kristiansand municipality in Southern Norway. In fact, the construction project is a complete reconstruction project, where the old Boen Foss plant is being upgraded into a completely new one. The old plant suffered heavy damage due to a severe flooding event that took place in 2017 fall and has been decommissioned ever since.
Suomen Voima’s subsidiary company SV Vesivoima Oy successfully took over the enterprise in summer 2018. For SV Vesivoima, it is the first single hydropower plant investment. Together with the completion of the development project Stardalen in 2021 and part ownership in the CSCTCA hydropower portfolio, the total amount of SV Vesivoima’s hydroelectricity production can very well be over 100 GWh per year.
The new 3,4 MW plant will yield approximately 23 GWh of annual hydroelectricity (the old plant yielded around 6,0 GWh). For environmental reasons, the run-of-river plant will use around 45 % of the Tovdalselva river’s yearly inflow, hence the plant will run on full load during most of the year. The plant is planned to operate continuously during normal conditions, harvesting the mechanical energy of the river’s water flow with a Z-type Kaplan turbine.
Suomen Voima’s Director of Development Pekka Saijonmaa points out, “As the plant uses only part of the river flow, the annual production profile is relatively flat, close to baseload. This differs the plant from other small-scale run-of-river plants and converges the value of the production close to the average market price.”
The construction of the new power plant has been ongoing for already a year. The concrete work for the water intake along the old dam has been completed and a fish pass inlet is in progress and close to completion. The concrete works for the power stations have been completed and the facade of the power house is expected to be completed within the following weeks. The grid connection work is in progress.
Before the powerhouse can be completely sealed and prepared for trial operation phase, the turbine and generator complex need to be installed. A slight delay for this phase is foreseen due to the unfortunate circumstances related to the COVID-19 pandemic. The pandemic has affected many industry sectors, thus the delivery of the turbine and generator has been postponed closer to the summer period. Once they arrive and have been installed, finishing touches to the power stations will be concluded and the trial operation period of the hydropower plant can be commenced.