To understand the development of Norsk Hydro operations in Rjukan, we look at the industrial activity that was divided into three phases:
Rjukan I
This phase was typified by often challenging construction projects on steep and difficult terrain. With production using the electric arc method, this initial phase was based on electricity from Vemork, 4.5 kilometres to the west, put into operation in 1911.
The factory buildings located on the south side of the Måna River were built on land that had belonged to the Såheim farm. The Pump House on the banks of the river was completed in 1910, with additional Rjukan II buildings (now designated as significant objects) completed the following year:
- Furnace House I
- Boiler House
- Barrel Factory
- Pump House
- Laboratory
Rjukan II
The Rjukan II phase was also based on the electric arc technology, and these Norsk Hydro operations began upon the opening of the new Såheim PowermPlant on 2 December 1915. Located one kilometre to the east of the factory area, the Såheim Power Plant also contained the Furnace House II, which produced nitrogenous gas, then fed by pipeline to the original Tower House (now demolished).
The expansion that resulted in Rjukan II began the year that Rjukan I became operational in 1911. By 1916, the work had been completed. The new additions included 35 Birkeland/Eyde furnaces inside the power plant with an accompanying boiler house as well as ventilation house (demolished), 5 gas pipelines and a tower house containing 50 granite towers and 10 iron towers, divided into 10 rows.
There was also a large Tower House (10,000 m2) with an accompanying evaporation reduction plant for sodium nitrate. Rjukan II also featured a facility designed to produce concentrated acid. In addition, expansions and improvements were made to the lime dissolution plant, evaporation reduction plant, crushing plant and the packing plant.
From the Såheim Power Plant to the Tower House, a one-kilometre system of aluminium pipelines was installed in 1926, and additional Birkeland/Eyde furnaces were installed – two in Furnace House I and four new ones in Furnace House II. All of these facilities in Rjukan II continued in operation until the New Production Facilities were put into use in 1929.
Rjukan III
These were the New Production Facilities put into operation in 1929, using the ammonia (Haber-Bosch) method. This required major infrastructure adjustments by Hydro, including:
- Conversion of the Vemork and Såheim Power Plants to supply electricity in direct current in addition to continuing to supply power in the original method.
- Facilities were constructed at Herøya, located on the southern coast of Telemark to convert the ammonia into mineral fertiliser.
Rjukan III would continue the production of fertiliser as well, contributing 40% of Hydro’s annual production of 70,000 tonnes.
Unlike in Germany, where coal was used for the production of hydrogen, hydrogen electrolysis was chosen in Norway where there was almost unlimited access to both water and electricity. The actual ammonia production process was otherwise identical to the one used in Germany.
The most important facilities at Rjukan III were all completed in 1928 with the exception of the Synthesis Plant. All facilities became operational in 1929:
- Nitrogen Plant
- Compressor House
- Synthesis Plant
- Mechanical Workshop
Hydrogen plants were built in front of Vemork and at Såheim in front of each respective power plant building, as direct current could not be transmitted over any distance without major power loss. Both of these hydrogen plants have been demolished.
The Hydrogen Plant at Vemork would later become another story that is still being talked about today.
Special thanks to NIA for all photographs