Wind energy: Intolerable loads on Austria's electrical transmission lines


In agreement with an E.U. objective Austria is planning to increase the share of renewable energy sources in electricity production from 70 % currently to 78 % in the year 2010. Currently wind power is booming.

"It is important to keep in mind that this eco-power cannot be reasonably transported to the consumers without an adequate grid", said Dr. Herbert Schröfelbauer, Chairman of the Research and Environment Committee of VERBUND, Austria's leading electricity company, at a press conference in Vienna on Tuesday. "There is no getting around the construction of new high-voltage transmission lines in the near future."

Due to support programs and favorable wind conditions the construction of wind power plants with a total capacity of more than 1,000 megawatt in the northeast of Austria is being planned at present. This corresponds to approximately seven percent of the total power-generating capacity available in Austria at present, exceeding the capacity of Zemm-Ziller, the most efficient VERBUND power plant group.

"The dimension of this new power plant capacity, the local concentration of the new wind power plants, and the variable output constitute an enormous challenge for our transmission line network, which has already reached its power-handling capacity today", said Dr. Heinz Kaupa, Engineering Manager of VERBUND-Austrian Power Grid AG (APG), Austria's largest electricity transporter.

As the 380-kilovolt-ring within Austria is still incomplete, the 220 kV lines are extremely loaded from time to time already today. The forthcoming wind energy boom is an additional challenge for the APG transmission line network. "Higher capacities in the domestic grid are indispensable, especially for boosting wind energy", said Mr. Kaupa, pleading for the quickest possible construction of the missing 380 kV lines in Styria and in Salzburg.

"The VERBUND grid in its present state can integrate wind energy only to a very limited extent", confirmed Univ.-Prof. Dr. Günther Brauner, Head of the Institute for Electrical Plants and Energy Management at the Technical University of Vienna. The integration of 1,500 megawatts of wind energy will load the grid to a level of 165 %. If some line systems fail, the network load can even increase to 245 %. Prof. Brauner: "In either case the VERBUND grid will be overloaded intolerably."