Condensing power stations took a leap forward as steam turbine technology started to become technically feasible around year 1900. The pioneering work of Parsons, De Laval and the Ljungström brothers resulted in the dual flow turbine which significantly increased the efficiency and output power. Steam turbines became the standard setup for power generation plants over the years to come, making the classic reciprocal steam engine obsolete in this field. However, as energy prices soared in the 1970s, condensing power stations only generating electricity instantly became terrible uneconomical (efficiency from fuel to electricity is somewhere around 35% !) and were typically shifted to be auxiliary backup stations instead, given their comparable short startup time.
This unit at Västerås in central Sweden was built in 1915-17 with ten smaller boilers and a 7 MW turbine and generator. A huge vertical boiler was built in 1931 according to the absolute frontline of technology of that time. The design proved to be a great success and the ever increasing demand for electricity made the small boilers obsolete and a new giant vertical boiler was completed in 1937 which at that time became the largest in Europe.
The boilers, turbines and electrical systems were exceptionally advanced of that time and the site seems to have attracted a vast number of international visitors from several countries. Electrical equipment manufacturer ASEA (the first 'A' in today's engineering giant ABB) was of course keen to show a working site in their home town, and this reference plant surely generated good business for them.
Coal fired plants like this was a dirty business (well, it still is, but let's leave it there) and in the 1920s, it was said that the town was choking in smoke, soot, ashes and sulfurous fumes. The plant consumed some 2000 metric tons of coal daily when operating at full power. Given the short height of the smokestacks, it is easily understood that it must have been a terrible pollution in the vicinity, especially in cold days. The 1937 boiler included a new innovation - the electrostatic filter, which added some relief in removing soot and ashes. After WWII, the shortage of coal made oil an economic alternative and the extension of the power plant in 1950-52 introduced oil firing. The plant was significantly expanded in 1959, but turned out as a fiasco as the municipality of Västerås built their own power plant. This new plant introduced district heating, thereby significantly increasing the overall efficiency and economics of a condensing power plant. Therefore, the 1959 boiler ended up as just another condensing one after just four years, presumably leading to a retirement of the earlier P11 and P12 boilers.
It's an fascinating to consider that the Västerås plant was for a short period after the 1948 expansion the second largest fossil-fuel power station in Europe, only second to the famous Battersea Power Station in London. Given that Sweden has no commercially viable domestic coal sources, the station was however used mainly at peak demand where the hydropower resources were not enough.
Apart from steeply increasing oil prices, the significance of the Västerås plant further diminished during the 1970s as Sweden made a massive investments in nuclear power, which ultimately put the site's story to an end in 1982 - at least from an operational/commercial point of view. The plant was however kept for some ten more years as a fully functional auxiliary backup, but in 1992 it was finally decided that the plant was to be decommissioned for good and it was assumed that the facilities were to be bulldozed. However, the equipment is still more or less intact and the owner's seems to have been strict in keeping intruders, scrappers and UE people out.
There are today advanced plans in converting the plant to a recreation center, and although this seems to be an attractive option compared with just bulldozing the building, it feels a bit sad that this remarkable piece of engineering remains will be gone forever. Given its long time of evolution and continuous extensions and modifications, the place is today an absolutely fascinating place for anyone interested in "heavy engineering" of ancient time, and the pictures here have been organized to show the tremendous variety that can be seen all over this site.