International Electrotechnical Exhibition

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Contemporary image showing the entrance to the exhibition site with arches and electrically powered waterfall Lauffen-Frankfurt 1891d.jpg
Contemporary image showing the entrance to the exhibition site with arches and electrically powered waterfall
International Electrotechnical Exhibition of 1891 on the site of the former Western Railway Stations at Frankfurt am Main IEAFrankfurt1891a.jpg
International Electrotechnical Exhibition of 1891 on the site of the former Western Railway Stations at Frankfurt am Main
The transmission route Drehstromuebertragung Lauffen-Frankfurt.png
The transmission route

The 1891 International Electrotechnical Exhibition was held between 16 May and 19 October on the disused site of the three former "Westbahnhöfe" (Western Railway Stations) in Frankfurt am Main. The exhibition featured the first long distance transmission of high-power, three-phase electric current, which was generated 175 km away at Lauffen am Neckar. [1] As a result of this successful field trial, three-phase current became established for electrical transmission networks throughout the world.

The Frankfurt western stations were a group of three stations on the western edge of the former city walls of Frankfurt am Main, Germany between the modern Willy-Brandt-Platz, then the location of Gallustor and Taunustor. They were replaced by Frankfurt Hauptbahnhof in 1888.

Three-phase electric power Common electrical power generation, transmission and distribution method for alternating currents

Three-phase electric power is a common method of alternating current electric power generation, transmission, and distribution. It is a type of polyphase system and is the most common method used by electrical grids worldwide to transfer power. It is also used to power large motors and other heavy loads.

The kilometre, or kilometer is a unit of length in the metric system, equal to one thousand metres. It is now the measurement unit used officially for expressing distances between geographical places on land in most of the world; notable exceptions are the United States and the road network of the United Kingdom where the statute mile is the official unit used.



The "Elektrotechnische Gesellschaft" (Electrotechnical Society) was founded in Frankfurt in 1881 with the aim of promoting electricity and, in particular, furthering research into its application for industry and technology. Three years later, some ten manufacturers of electrical equipment had set themselves up in the city. In around 1890, some of the enterprises were established which would later become major firms in Frankfurt: Hartmann & Braun, Staudt & Voigt (from 1891 Voigt & Haefner) and W Lahmeyer & Co (from 1893 Elektrizitäts-AG, previously W Lahmeyer & Co). And it was in Frankfurt that the "second industrial revolution" began to emerge – a revolution that would bring about fundamental changes similar to those created 100 years previously by the introduction of the steam engine to the world of work. In 1891, the German electrical industry was ready to demonstrate its capabilities to the world at the International Electrotechnical Exhibition. A site was chosen – that of the former western stations between the city and the new main station, which had been completed in 1888.

Steam engine Heat engine that performs mechanical work using steam as its working fluid

A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force is transformed, by a connecting rod and flywheel, into rotational force for work. The term "steam engine" is generally applied only to reciprocating engines as just described, not to the steam turbine.

Frankfurt (Main) Hauptbahnhof main railway station in Frankfurt, Germany

Frankfurt (Main) Hauptbahnhof, often abbreviated as Frankfurt (Main) Hbf and sometimes translated as Frankfurt central station, is the busiest railway station in Frankfurt, Germany. The affix "Main" comes from the city's full name, Frankfurt am Main. Because of its location in the middle of Germany and usage as a hub for long and short distance travelling, Deutsche Bahn refers to it as the most important station in Germany.

Prompted by the Paris "Exposition Universelle" (World Fair) of 1889, Leopold Sonnemann, publisher of the Frankfurter Zeitung newspaper, interested the Electrotechnical Society in the idea of an exhibition. The Society expressed an interest and started preparations in the same year. However, there was another consideration apart from the setting up of an international exhibition – Frankfurt had an urgent problem to solve. The construction of a central power station had been under discussion in the city’s political and technical committees since 1886. However, agreement had still to be reached over the type of current, and opinions were divided between direct current, alternating current and three-phase current. It fell to the exhibition to demonstrate a commercially viable method for the transmission of electricity. Three-phase current with a minimal loss of 25% would be transmitted at high voltage from Lauffen am Neckar to Frankfurt. This took centre stage at the exhibition and was evidenced in the large three-section entrance gate. The central section took the form of an arch bearing the inscription "Power Transmission Lauffen–Frankfurt 175 km." Rectangular panels flanked the arch: the one to the right carrying the name of the "Allgemeine Electricitätsgesellschaft" ("AEG" – General Electricity Company), which had been founded in 1887; the left-hand panel displayed the name of the "Maschinenfabrik Oerlikon" (Oerlikon Engineering Works). The entire entrance was illuminated with 1000 light bulbs and an electrically powered waterfall provided a further attraction. With 1,200,000 visitors from all over the world, the exhibition was an out-and-out success. The cost of a one-day entry ticket for an adult amounted to a considerable 15 marks.

Exposition Universelle (1889) Worlds Fair held in Paris, France

The Exposition Universelle of 1889 was a world's fair held in Paris, France, from 6 May to 31 October 1889.

Leopold Sonnemann German journalist and publisher

Leopold Sonnemann was a journalist, newspaper publisher, and political party leader in Germany during the periods of the North German Confederation and the German Empire. Publisher and editor of the Frankfurter Zeitung, Sonnemann also served as a deputy to the Reichstag and was a founding member of the German People's Party.

<i>Frankfurter Zeitung</i> periodical literature

The Frankfurter Zeitung was a German language newspaper that appeared from 1856 to 1943. It emerged from a market letter that was published in Frankfurt. In Nazi Germany it was considered the only mass publication not completely controlled by the Propagandaministerium under Joseph Goebbels.

As far as Germany was concerned, the International Electrotechnical Exhibition settled once and for all the question of the most economical means of transmitting electrical energy. When the exhibition closed, the power station at Lauffen continued in operation – providing electricity for the administrative capital, Heilbronn, thus making it the first place to be equipped with a power supply using three-phase AC. The name of the local power company (ZEAG) bears testimony to this event. The Frankfurt city council constructed its own power station near the harbour; yet another was built by a private company in the suburb of Bockenheim.

Power station facility generating electric power

A power station, also referred to as a power plant or powerhouse and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Most power stations contain one or more generators, a rotating machine that converts mechanical power into electrical power. The relative motion between a magnetic field and a conductor creates an electrical current. The energy source harnessed to turn the generator varies widely. Most power stations in the world burn fossil fuels such as coal, oil, and natural gas to generate electricity. Others use nuclear power, but there is an increasing use of cleaner renewable sources such as solar, wind, wave and hydroelectric.

Heilbronn Place in Baden-Württemberg, Germany

Heilbronn is a city in northern Baden-Württemberg, Germany. It is surrounded by Heilbronn County and, with approximately 123,000 residents, it is the sixth-largest city in the state.

Bockenheim (Frankfurt am Main) Stadtteil of Frankfurt am Main in Hesse, Germany

Bockenheim is a city district of Frankfurt am Main, Germany. It is part of the Ortsbezirk Innenstadt II.


A hydraulic turbine at Lauffen powered a three-phase alternator with a revolving field. The alternator revolved at 150 revolutions per minute, and had a rotating field magnet with 32 poles. It was rated at 300 hp and had a terminal voltage of 55 volts. The frequency of the current was 40 Hz. Power from the alternator was stepped up to 8000 volts for transmission by oil-insulated transformers. Later tests were carried out with transmission voltage up to 25,000 volts (between phases).

Revolutions per minute is the number of turns in one minute. It is a unit of rotational speed or the frequency of rotation around a fixed axis.

Horsepower unit of power

Horsepower (hp) is a unit of measurement of power, or the rate at which work is done. There are many different standards and types of horsepower. Two common definitions being used today are the mechanical horsepower, which is about 745.7 watts, and the metric horsepower, which is approximately 735.5 watts.

Volt SI derived unit of voltage

The volt is the derived unit for electric potential, electric potential difference (voltage), and electromotive force. It is named after the Italian physicist Alessandro Volta (1745–1827).

The transmission line was erected with the assistance of the German Post Office and used about 60 tonnes of copper wire, 4 mm in diameter. At the exhibition, the voltage was stepped down by further oil-filled transformers and connected to motors and a motor-generator system for lamps.

Tonne metric unit of mass

The tonne, commonly referred to as the metric ton in the United States and Canada, is a non-SI metric unit of mass equal to 1,000 kilograms or one megagram. It is equivalent to approximately 2,204.6 pounds, 1.102 short tons (US) or 0.984 long tons (UK). Although not part of the SI, the tonne is accepted for use with SI units and prefixes by the International Committee for Weights and Measures.

Millimetre unit of length 1/1000th of a meter

The millimetre or millimeter is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length. Therefore, there are one thousand millimetres in a metre. There are ten millimetres in a centimetre.

Overall efficiency from turbine to load was an average of 75%, which resolved many doubts of the practicality of long-distance electric power transmission. [2]

See also

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Electric generator device that converts other energy to electrical energy

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  1. Stefan Molęda. "Michał Doliwo-Dobrowolski – 120 lat elektroenergetycznego trójfazowego systemu przesyłowego w Europie (120 Years of the Three-Phase Energy Transmission System in Europe)" (PDF). Elektroenergetyka (in Polish). 2011 (3): 136. ISSN   2080-8593.
    • Silvanus P. Thompson, Polyphase Electric Currents and Alternate-Current Motors, E. & F. N. Spon, London 1895. Thompson gives a detailed description of the Lauffen and Frankfurt machines on pages 27–33, with illustrations. The transmission system is described on pages 106–110