Operation of the new chemical pulp mill, completed in 1898, was mainly based on direct water power. Motive power was needed for machines outside the works, too, e.g. for the goods lift and repair workshop. For this purpose, direct-current motors were purchased, and power fed to them from a generator manufactured by the Wahl engineering works. It was positioned in a hut at the side of the turbine room.

The pulp mill had electric lighting, and electricity was also distributed to the houses of the factory office staff. The lighting current was generated by a 110-volt turbodynamo manufactured by Strömberg. When the paper mills were established at the turn of the century, they were also given their own lighting current generators. At the end of the 1910s another two generators were obtained, and lighting electricity could now be sold to the factory village, too.

After the Jämsänkoski factories were merged with United Paper Mills, one of the first tasks was reforming the energy supplies. The new superintendent, Roope Hormi, found little steam engines scattered throughout the factories. Similarly, small water turbines were positioned here and there, utilising the fall of water poorly and using long shafts. In the superintendent's view, this kind of 'random organisation of power' resulted in massive waste of firewood. For each tonne of paper produced, the Jämsänkoski mill consumed almost twice as much firewood as the company’s other factories.

A power station was built at Rekolankoski rapids for electricity generation. The builder was Ab Skånska Cementgjuteriet and the two 330 horsepower turbines were supplied by Tampereen Pellava- ja Rautateollisuus Oy. The electrical equipment came from Strömberg in Finland and AEG in Germany. The power station started up at the end of the year 1922. Energy volumes produced by hydropower were directly comparable to water volumes; in poor water years energy production had to be supplemented using coal and wood. In 1926, the updated Patalankoski grinding mill was stopped and a 300 kW generator attached to the water turbine to produce electricity. At that time, the various factory units were using 38 electric motors, with a combined output of 1,750 horsepower.


In the mid-1930s, the Patalankoski grinding mill was stopped and a 300 kW generator attached to the water turbine to produce electricity. At that time, the various factory units were using 38 electric motors, with a combined output of 1,750 horsepower. A hydropower station was completed at the so-called Raikko branch of the rapids in 1936. Design of the plant was hampered by the great fluctuations in the water volumes of the river Jämsänjoki. The pressure tube of the tubular power plant was about 100 metres long with a diameter of 2.9 metres. The chosen turbine type was a Kaplan vertical turbine. The turbine and pressure tube complete with hatch was supplied by Tampereen Pellava- ja Rautateollisuus Oy. Electricity produced by the Jämsänkoski factory power stations was also sold to private consumers. Up to the 1940s, electricity supplies of the residential area depended on power sold by the company.

Electricity generation based on thermal power had taken a great step forward with the advent of high-pressure steam boilers and counter pressure turbines at the end of the 1920s. At that time direct current was also replaced with 380 volt alternating current. Expansion of the national power grid after the wars solved the energy shortage that had dogged the Jämsänkoski mills. The factories were connected to the national power line in 1949. A transformer and switching substation was built alongside the paper mill. The mill itself produced energy with water power and steam turbines. The share of self-produced electricity was on average 20 percent. At the end of the 1960s, self-produced electricity accounted for almost a third. Shareholder electricity to the United plants was supplied by Kemijoki Oy.

The energy requirements grew year by year. A special jump in electricity consumption was caused by the Kaipola mill starting up and its extensions. It needed more than half of all the energy consumed by United. At Jämsänkoski, moving over from chemical pulp based paper manufacture to mechanical pulp types in the early 1980s also meant a large increase in energy needs.

Link:  Power from the rapids [Finnish only]