APG: KEMA cable is not approvable


"Based on our experience, the concept of a partial cabling solution presented by KEMA consulting company in their appraisal on 28 January is not approvable in Austria.

." This is the verdict reached by VERBUND-Austrian Power Grid AG (APG) after having conducted a meticulous study of the documentation submitted within the setting of the presentation in Salzburg.

It can also be said with certainty that the contents of the presentation of 28 January 2008 and the ensuing statements based on that presentation to the public have not been adequately substantiated.

"A close examination of the appraisal reveals the obvious fact that a cable solution in the necessary capacity neither corresponds to a modern level of technology nor is approvable on the basis of our experience," is the surprised reaction of APG Chairmen of the Board Dr. Heinz Kaupa and Mag. Thomas Karall.

Upon close scrutiny of the documentation, APG has come to the following conclusions:

  • The dimensioning of the line does not comply with the approval requirements of the authority in charge.
  • There are no inspection results on any other system combinations proposed.
  • The specific risk accompanying a 380 kV cable is denied.
  • Based on the experience of APG, the exposure of man and the environment to the electromagnetic field caused by an underground cable renders the cable option proposed by KEMA non-approvable.
  • The costs have not been treated with the required professionalism.
  • The factually existing increased failure risk and/or the far longer time needed to repair cable systems would preclude a dismounting of the 220 kV line.

In summary, it has to be said that KEMA is not able to provide a feasible, sensible overall solution despite conveying the impression that, in principle, this is something that can be achieved.

"We are not going to endanger the security of supply for Salzburg, Austria, and, ultimately, Central Europe by conducting this type of experiment," says Kaupa, firmly rejecting the underground cable solution.

"After all, we have the responsibility for the grid operation and the security of supply. Based on the KEMA appraisal, we cannot by any means take this huge responsibility upon ourselves," Kaupa concludes.

Meticulous examination of the KEMA documentation reveals that an underground cable solution for the 380 kV line in the transmission grid does not correspond to the latest level of technology, since all specifications in the appraisal are based on a far lower dimensioning.

Oswald's expert appraisal, presented by E-Control on 18 January, unmistakably showed that, if based on an accurate dimensioning, a 380 kV cable does not constitute an acceptable option to an overhead line.

"E-Control's critical appraisal is of fundamental significance for APG. Because it is ultimately the regulatory authority that stipulates the framework conditions for the safeguarding of energy supply in Austria," APG Chairman of the Board Karall emphasizes.

"Mid April we are going to submit our detailed statement to the provincial government of Salzburg, and we will be happy to discuss the contents with the appraisal's authors. We wish to once again show our interest in a mutual cooperation with the government of Salzburg, the municipalities and the population, as well as in a transparent and objective process," the Chairmen of the Managing Board comment.

The main points of criticism of the KEMA appraisal are as follows:

Framework conditions for transmission lines

The appraisal is based on an incorrect interpretation of energy-relevant framework conditions. For instance, the fact that APG is "unbundled" in compliance with EU provisions and therefore has no influence regarding generation and supply curves in the grid was not taken into account.

The appraisal's author further assumes that the Salzburg line will in future increasingly represent a transitional transmission line. In actual fact, the load is determined by requirements in Salzburg and throughout Austria.

Likewise, the grid load scenario depicted in the appraisal by APG for Austria by 2020 was simply changed to 2050 without taking into account the increase in figures expected until then.

The dimensioning of the line does not correspond to the officially granted expansion dimension

The notice of approval regarding the expansion of the 380 kV ring in Austria applies to an output of 2x2400 MW ("n-1"-precisely: 2x1375 MVA) as an overhead line.

Even with the most optimistic of assumptions, the dimensioning of the two cable systems discussed in detail by the author in the appraisal is significantly below this figure. With that, the future safeguarding of the security of supply in Austria is in jeopardy.

The appraisal's author also proposes to resort to additional systems if the need arises, without, however, examining these in detail.

Grid operation safety and risk

The proposed cabling systems, at any rate, would lead to shortages as early as 2020, which could then only be counteracted by means of congestion management.

The statement that the failure rate for overhead lines and cable lines is about the same is misleading, because the regular switching off of overhead lines for maintenance purposes is put on one level with the unexpected and long-lasting outages of cable lines in critical net situations.

The statistics employed here refer exclusively to the cable system of Berlin. The outage in 2006, however, which  lasted for weeks, failed to be taken into consideration.

For APG, this does not represent a basis upon which to guarantee the security of supply, because, in particular, the expert opinion of Professor Oswald (on commission by E-Control) shows that the risk of cabling is 40 times as high as that of overhead transmission lines.

Costs presented reflect a line with too low an output

The discussion of the tariff effects only takes account of the costs of an undersized cable solution.

It is incorrect to allocate investment costs to the entirety of Austrian households, because the costs of the investment can only be applied in the control area East (Austria without Tyrol and Vorarlberg).

The regulatory authority, moreover, already publicly announced on 18 January 2008 that it would not accept any additional costs for cable in the 380 kV ring.

The subject of health was completely disregarded

The installation depth of 1.2 m, recommended in the appraisal on the basis of cable manufacturer information, would generate an electromagnetic field at the earth's surface the strength of which would by far exceed the limit recommended by the WHO of  100 μTesla, thus, on the basis of the experience of APG so far, barring a project of this type from approval.

Installing the cable at a lower depth would, as a result of the necessary cooling, further reduce the available transport capacity of the cable. Cooling systems are costly and come with a high outage risk, which would further increase the failure risk for a cable line.