Dispersion Calculation According to "TA Luft" in a Complex Structured Area - Application of Alternative Calculation Methods

Project Number 312

When planning new power plants in Germany the additional immission load in the surrounding of a plant has to be calculated with the dispersion model of the German regulation "TA Luft“. This standard method may only be applied if the inclination of the surrounding area is less than 1:5 and if local wind systems and other meteorological anomalies can be excluded. This criterion is not fulfilled in the low mountain regions in Germany for a great number of possible power plant sites. For these cases a calculating procedure is not defined up to now. The licensing procedures for such sites are thus not regulated. In many cases this leads to an increased need of a detailed explanation and to massive efforts of objectors in public licensing procedures to put the present investigations into question.

The VDI has picked up this problem and installed a task force to create a VDI guideline in which methods shall be described, how such cases can be handled when you are out of range of application of the TA Luft. There are two methods discussed both being based on extensive flow calculations with prognostic meso-scale models which have already been applied several times in licensing procedures.

Experts of the VDI task force shall carry out comparative calculations with both methods and with the TA Luft standard method. Only in this way it will be possible to guarantee the objectivity of the process descriptions and to define criteria under which conditions which method will have to be applied. So it is imaginable to relax the restrictive application limits of TA Luft as far as similar results are gained compared to the extensive prognostic method.

The project will be carried out between May 2008 and May 2009 by the following institutions: 

  • METCON Umweltmeteorologische Beratung, Pinneberg (Project management: Dr. Klaus Bigalke)
  • Ingenieuerbüro Lohmeyer GmbH & Co. KG, Karlsruhe (Project management: Dr. Thomas Flassek)
  • iMA Richter & Röckle Niederlassung Stuttgart (Project management: Dr. Jost Nielinger)

The Technical Committee Air Pollution and Noise Control supports the investigations.