The Harjavalta hydropower plant celebrates its 70th anniversary

The completion of the Harjavalta hydropower plant 70 years ago was celebrated with an open doors event on Wednesday 11 November 2009. The inhabitants of the region were welcomed to visit the plant.

During the past autumn, the Melo and Kolsi transmission lines source towers at the power plant on both sides of the river Kokemäenjoki were renewed and the old end towers on the roof of the power plant were dismantled. At the same time, the power transmission connection from the power plant to the transmission line had to be upgraded. In addition, the equipment at the 110-kV substation was revised and partially refurbished. The renovation work will continue in the winter.

The 73-megawatt Harjavalta hydropower plant with its 400 GWh annual electricity production is still one of the largest hydropower plants in Finland. The fall depth of 26.5 metres is, similarly, relatively high in Finnish conditions. The plant is owned by UPM-Kymmene Corporation, Pohjolan Voima, Statkraft Suomi Oy, the City of Pori and Pori Energy. PVO-Vesivoima Oy, the hydropower subsidiary of Pohjolan Voima, is responsible for the operation and maintenance of the plant.

The first plans for the hydropower construction were drawn already during the First World War when energy was in dire need. Many over-sized projects had to be abandoned for lack of necessary resources. This was initially also the case for Harjavalta construction plans, with the highly dispersed ownership of the waterways along the downstream part of the Kokemäenjoki river considerably stalling the beginning of the construction. The plans were finally starting to materialise in 1937 when the hydropower plant construction work at the present plant location was begun.

70 years ago the construction site saw busy and uneasy times. The instalment of the equipment was making good progress, but the Finnish economy was faced with the dark clouds of the Second World War looming in the horizon. The first machine unit was completed and connected to the national grid at Christmas Eve, 1939 to bring power and light to the darkness in otherwise extremely hard times. The second machine unit was connected to the grid the in the following spring.