Transmission system - technical details

Transmission System Route

Protective band, as provided for in Act No 458/2000 Sb., as amended ("Energy Act") is the area in the immediate vicinity of the equipment. The protected range is designed to secure reliable operation and protect persons' life, health and property.

The protected range shall arise on the effective date of a zoning decision on the project placement, effective date of a public contract replacing the zoning decision or of legal effects of a zoning approval on the building placement. In case none of the above-mentioned documents is required pursuant to the Building Act, the effective day shall be the day of launching the power system in operation

Protective bands are set up to protect, among others, overhead lines, underground lines, electric stations of the transmission system.

The protected range of the overhead line is a continuous band delineated by the vertical planes along both sides of the line at a horizontal distance measured perpendicularly to the line. This distance from the marginal line on both sides shall be as follows:

  • over 35 kV and up to 110 kV inclusive………………….12 (15) m 
  • over 110 kV and up to 220 kV inclusive………………...15 (20) m
  • over 220 kV and up to 400 kV inclusive………………...20 (25) m
  • over 400 kV…………………………................................30 m

Given the fact that the protective bands as set in the field of electric energy and heating pursuant to legal regulations in force are not changed with the Act having come in force, the values in brackets shall be valid for protective bands of overhead lines with approval decision having come in force until 31 December 1994, i.e. before the effective date of Act No. 222/1994 Sb.

Identically, exceptions to protective bands regulations granted based on legal regulations in force shall remain valid also following the effective date of Act No. 458/2000 Sb., as amended.


The protected range of underground line shall be delineated by the vertical plane on both sides of the marginal line, the distance is as follows:

  • up to 110 kV……………………………..........…..............1 m
  • over 110 kV…………………………….............................3 m


The protected range of outdoor electric stations and stations at voltages over 52 kV in buildings shall be delineated by vertical planes at a horizontal distance of 20 m outside from the fence or in case the station is not protected by fence, 20 m from the outer face of circumferential walls.


Within the protected range of the overhead and underground lines as well as electric stations it is not allowed to:

  • Erect any buildings, install any structures or any other objects or store any flammable and explosive materials without the consent of the owner of the respective equipment;
  • Perform any earthwork without the consent of the owner of the respective equipment;
  • Perform any activities which might affect reliable and safe operation of the electric equipment or impose a threat to the life, health, and property of persons;
  •  Perform any activities that would block or substantially limit access to the respective equipment.


Within the protected range of the overhead line it is not allowed to plant hop fields. Moreover, the height of any plant shall not exceed 3 m.

Within the protected range of the underground line it is not allowed to plant permanent crop stands and ride over the line with machines having a total weight over 6 tons.

Activities performed within the protective range as well as outside the range must not damage electric equipment. Anyone within as well as outside the protected range is obliged to refrain from any actions that may imply risks to the power system or restrict or threaten its safe and reliable operation. Moreover, any activities shall be pursued in a way to prevent any damage to the electric equipment.


Types of towers used by ČEPS

The transmission system is composed of a number of various elements, each of which performs a specific function. Transmission towers provide support and ensure the physical separation of individual phases within the power line.

The ČEPS backbone transmission system carries 220kV high voltage power and 400kV extra high voltage power. Accordingly, transmission towers are higher and stronger than other towers within the national power system. A specific type of tower is selected according to the required tower strength and lifetime, line route, climatic and weather conditions and the respective voltage level. Towers are designed to withstand extreme weather conditions, such as ice coating or violent storms.

The above-ground tower foundation segment usually consists of four concrete cylinders approximately 90 cm in diameter and at least 40 cm in height. Each tower leg is anchored to one of the cylinders. The area covered by the tower's foundations is approximately 60m2, including the mandatory 1m wide protection zone delineated by vertical .planes of lines connecting outer contour edges of the tower foundations outside the ground plan.

Types of towers for download.