Another critical situation in Austria’s electricity network

5/24/2006Wien

A critical situation prevails in Austria’s national high-voltage grid. As the VERBUND-Austrian Power Grid AG (APG) advises, the current extreme wind power generation in Northern Germany and the failure of a power line in the Czech Republic are also putting a lot of pressure on the Austrian high-voltage grid. The APG is working intensely on maintaining the stability of the electricity network.

On account of the current weather situation, the electricity production in German wind farms is running at full speed. As a result, an extremely high strain is additionally being placed on the European grid. Alongside this, there is the failure of the Hradec-Etzenricht line between the Czech Republic and Germany. This is causing extreme aggravation to the network situation in Central Europe, and also in Austria accordingly.

Together with the electricity network operators of the neighbouring countries, the APG is working on stabilizing the situation. Thus, among other things, APG power lines currently undergoing inspection are being carefully put back into operation. As the wind power forecast in Germany anticipates a continued high production volume in the coming days, the APG are mobilizing additional personnel to cope with the critical situation.

In detail, the network situation looks as follows:

In the European power grid (UCTE network), there is an increasingly critical network situation on account of the extremely high wind power generation in Germany. The situation is currently being aggravated by the failure of the important Hradec (CZ)-Etzenricht (D) power lines on 20.5.2006 at 8.30 p.m. As a result of the failure, an additional strain was placed on both of the remaining connecting lines.

Since the morning hours of 23.5.2006, with a current 11,000 MW (of approx. 18,500 MW installed capacity), the wind generation in Northern Germany is leading to a higher strain on the two remaining power lines between Germany and the Czech Republic. In addition, the safety limit on the connection lines between Austria and the Czech Republic has been exceeded. On account of this, an increased risk of failure can be reckoned with in Austria - especially if one of the two remaining power lines between Germany and the Czech Republic fail.

On 23.5.2006 at 10.23 a.m., the APG informed its neighbouring power grid operator about the very critical network situation on the Austrian-Czech border, and asked it to begin the necessary relief measures in collaboration with APG. In the APG network, line disconnections being carried out for overhaul works were stopped and postponed on account of the critical situation. In connection with the failure of the Hradec-Etzenricht power line, an increased stand-by service was ordered at APG.

A relaxation of the situation is to be first reckoned with through the reconnection of the Hradec-Etzenricht power line and a reduction in the wind power generation in Germany. However, the wind generation forecast in Germany anticipates similarly high exports for the next days.

In times of high wind generation in Northern Germany, higher flows of power occur in the UCTE network from the North to the South. In the process, the surplus generation of wind power finds its way to the consumers via the law of physics. The effects can be seen in the Czech Republic, Poland, Austria, Slovakia, Hungary and even Slovenia with a strongly increased flow of power as a result. In addition to a higher strain on the connection line between Germany and the Czech Republic, there is also a great strain on the line between the Czech Republic and Austria.

The line connections between the Czech Republic and Austria comprise of the presently single system 380-kV line Dürnrohr (A)-Slavetice (CZ) and the dual system 220 kV line Bisamberg (A)- Sokolnice (CZ). If the pressure on the two lines exceeds the mandatory security limits, there exists the great danger that the failure of one of the line systems would result in the failure of both of the connection lines. The result would be high and sudden shifts in the transport power from Austria to power lines in Germany, the Czech Republic, Slovakia and Hungary. This holds the high danger of the resulting failure of lines in neighbouring states and of an increase in disturbances in Austria as well.