The generation, transport and use of electrical energy are inevitably connected with the occurrence of low-frequency electric and magnetic fields. However, no research study to date has proven that these are harmful to health as long as the maximum permissible levels are not exceeded. When constructing new facilities, 50Hertz ensures, through a range of diverse measures, that the legally prescribed limit values are not exceeded. As a rule, levels are kept considerably lower than the maximum permissible values.
The strength of the electric and magnetic fields is dependent on the distance of the overhead line conductors from the respective object, and on the way the conductors are positioned on the tower. In the case of electric fields, the operating voltage is of importance, while in the case of magnetic fields, it is the strength of the current flowing through the conductors. With increasing distance from the power line, the strength of the electric field as well as the magnetic flux density decrease rapidly. A large number of scientific facilities and institutions have conducted long-term research into the possible damage to health caused by low-frequency electric and magnetic fields in the proximity of overhead lines. None of these studies have produced evidence of damage to health as long as the maximum permissible levels are not exceeded.
With all its new construction projects, 50Hertz considers possible risks, commissions environmental impact studies and works closely with the local environment and forestry authorities in order to develop the best solution. Densely populated areas are avoided, and landscape preservation is accorded high priority by 50Hertz during corridor planning. As a consequence, provisions are made for bundling transmission routes with existing overhead line runs wherever possible. Similarly, during planning, the possibility of bundling transmission routes with other infrastructure elements such as railway lines and motorways is considered. In order not to disturb the landscape unnecessarily, the routes are planned to blend as closely as possible into the given landscape Features.
The general legal basis for the protection of the population is the Federal Immission Control Act (BImSchG). The protection against adverse effects on personal health as a result of electric and magnetic fields was regulated in the 26th Ordinance implementing this act on 16/12/1996. It established a limit value of 5 kV/m for electric field strengths. For the magnetic flux density, it is approximately 100 mictrotesla. Both limit values, which apply “in buildings and on properties where people reside longer than temporarily”, are respected by 50Hertz when planning grid expansion projects and in many cases the actual values fall short of these limits.