The Star That Sparked Europe's Power Grid

Star of Laufenburg named IEEE Milestone

6 April 2010

This article has been revised to reflect a correction in the installation date for the plaque.

As Europeans emerged from the physical and economic destruction of World War II, it became ever more apparent that the availability of plentiful, reliable, electric power would be key to the continent’s progress and recovery. That required the sharing of power across national borders. Today, 34 countries’ transmission systems are linked, from Finland to Portugal and from Iceland to Greece.

Europe’s electrical integration began modestly in 1958, with a 220-kilovolt connection between France, Germany, and Switzerland. That connection, known as the Star of Laufenburg, the first high-tension link between the three countries, is being honored as an IEEE Milestone in Electrical Engineering and Computing.

Actually, Europe’s first transborder power links predate World War I. Laufenburg itself is home to a run-of-river generating station driven by water from the Rhine that dates to 1914. Set on the border between Germany and Switzerland, it sent power to both countries via a low-voltage network. But the 1958 link, which added France and used 220-kV lines for higher capacity, became the heart of the power grid in Western Europe. The Laufenburg substation connects 12 380-kV and 10 220-kV transmission lines and is a key node in Europe’s interconnected system.

The dream of a Europe-wide grid goes back at least to the 1920s, but its advantages gained even more importance as Europe rebuilt after World War II. Interconnecting electric power systems can make power less expensive and more reliable, conserve resources, and reduce carbon emissions and pollution. That’s especially true when the systems’ energy inputs come from varied sources, such as run-of-river generators, hydropower dams, and thermal power stations.

The output of run-of-the-river power plants varies with river flow. The output from dams is constrained by the flow from the rivers behind, the water needs of downstream users, and the need to protect downstream land from flooding. An optimal hydrothermal mix allows reduction in thermal-plant output when hydropower is plentiful, conserving fuel and reducing smokestack emissions. Furthermore, during low load periods, thermal power can be used to pump water back into reservoirs, for use during dry spells or to ensure adequate power during peak load—in effect, sharing reserves to increase reliability while reducing costs.

Laufenburg was chosen for that first tri-country interconnect because space was available on the Swiss side, a hydropower plant was already operating there, and the terrain between the interconnect and the French border, some 50 kilometers away, was relatively flat. Laufenburg was also headquarters to one of the utilities behind the interconnect—which later took over the role of system coordinator as EGL (Elektrizitäts-Gesellschaft Laufenburg).

From Laufenburg, connections grew. In 1967, the Star network was boosted from 220 kV to 380 kV, and a switching substation was built for a 17-country interconnection. Over the years regional grids have been interconnected to make a pan-European transmission network, which is coordinated under the aegis of the new European Network of Transmission System Operators for Electricity (ENTSO-E).

The IEEE Milestone Program in August is honoring the “Star of Laufenburg” interconnection with the installation of a plaque near the main gate of the complex. The plaque reads:


Star of Laufenburg Interconnection, 1958
This is the original location of the electric-power interconnection of three countries: Switzerland, Germany and France. The Union for Production and Transmission of Electricity (now UCTE) was formed to manage this interconnection. This installation pioneered international connections, and technical and political cooperation for European integration. UCTE coordinated one of the largest synchronously connected power networks serving almost all of continental Europe.


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