After recent in-depth economic, ecological and legal examination, the APG has gained the opinion through these comprehensive investigations that cabling or part-cabling of the 380-kV Styria power main is not justifiable on technical, ecological and economic grounds. Cabling has extremely serious negative effects on certainty of supply and in addition would be an energy industry experiment. This position will be supported unanimously by all European network operators. Cabling in the 380-kV-transmission network is not state-of-the-art technology. In Europe, of more than 100,000 kilometres, only some 100 kilometres are cabled, namely where nothing else can be used, such as urban areas and airports.
The following factors are against cabling or part-cabling of the Styria power main:
• Considerably less certain operation in comparison to overhead lines, and down times for repairs lasting one or two months with severe effects on certainty of supply on extensive parts of the Austrian power supply network.
• A cost ratio of 1:8.4 between overhead lines and cabling.
• Part cabling of 10 % to 20 % would, in addition to the described ecological effects in the cabled sections, lead to a doubling or tripling of costs in comparison to the costs for overhead lines. And here the clear uncertainty of operation has severe effects on certainty of supply.
• Cabling the 380-kV main also represents a considerable negative ecological assault on the environment, including the drying out of soil under the warming effect of the cable and the consequent change to water balance.
The ecologically serious effects of the building phase for the 30-metre wide cable route will, together with the technical and economic problems, be assessed negatively by experts and also several specialists in their UV reports.
Since the year 2001 the absolute limits of mains loading were hugely and lastingly exceeded on all APG North-South high tension power lines. This brought about a considerable increase in the risk of an extensive power failure. Indeed in 2003 the consequences were seen of such overloading, for instance in the Italian blackout and other network interruptions. In Austria a similar network collapse was until now only avoided through fortunate circumstances coupled with emergency measures in the form of comprehensive and expensive bottleneck management.
Only recently, another investigation by the TU Graz revealed that only through the immediate connection of the 380-kV-ring in the area of the Styria power main and the Salzburg main is it possible to achieve secure operation of the transmission network in Austria. Only with a secure and highly efficient 380-kV-ring can on the one hand the annual consumption growth be met and on the other hand the rapid and huge increase in new regenerative sources of energy, in particular wind energy. Furthermore the 380-kV-network extension is a prerequisite for access to the European energy market, which for its part enables competitive prices to be offered to the Austrian economy.
For the immediate modernisation of the critical overloading of the North-South main in the APG high tension network, at the end of 2003 APG submitted an overhead line project optimised from a technical, economic and ecological point of view for connection of the eastern part of the 380-kV-ring for approval under the UVP law to the provincial governments of Styria and Burgenland. The objective aimed for and always communicated was the completion of the 380-kV main by 2006, not least of all because the inevitable connection of thermal power stations in southern Austria from 2006 will unbearably increase the already critical situation for Austria.
In preparing the project submission, the APG dealt extremely intensively with the alternative of cabling. These investigations are a component of the environmental friendliness declaration submitted to the UVP (UVE). The now recently carried out examination from a technical, economic, ecological and legal point of view has led to no new findings.
Finally the APG again points out that the summary UV reports to the authorities come to the conclusion that the overhead line submission is environmentally friendly.