The transmission grid transports electrical energy at extra-high voltage (220 kV and 380 kV) over long distances. It connects large power plants, offshore wind farms, and distribution grids with one another and ensures large-scale balancing between generation and consumption. The transmission grid is the invisible but absolutely decisive infrastructure that keeps entire national economies running.
What tasks does the transmission grid perform?
It transports electricity over hundreds of kilometers with minimal losses, enables Europe-wide electricity exchange, integrates large renewable generation units, and secures grid stability through frequency control reserves. Transmission system operators (TSOs) are responsible for its operation and coordinate with one another Europe-wide via ENTSO-E.
Key Characteristics at a Glance
- Extra-high voltages from 220 kV to 765 kV
- Large-scale load balancing between regions
- HVDC lines (high-voltage direct current) for very long distances
- Meshed grid structure for high redundancy
- Integration of European power grids via ENTSO-E
- High-voltage direct current transmission for very long distances
- Close interconnection with neighboring countries for security of supply
Frequently Asked Questions
What is HVDC and where is it used?
High-voltage direct current transmission converts alternating current into direct current, transmits it over long distances with very low losses, and converts it back at the destination. HVDC is mainly used for long-distance connections, submarine and underground cables, and the connection of offshore wind farms.
Who operates the transmission grid in Germany?
Four transmission system operators – 50Hertz, Amprion, TenneT, and TransnetBW – are responsible for their respective control areas. They are obligated to operate the grid on a non-discriminatory basis and work closely together across Europe.
How is the German transmission grid being expanded?
The Federal Network Agency (Bundesnetzagentur) regularly publishes the grid development plan, which describes the necessary expansion. Major projects such as SuedLink, SuedOstLink, and Ultranet are intended to bring wind power from northern Germany to the load centers in the south. Approval and construction take many years.
How is a new transmission cable laid?
Underground cables are laid in trenches or using trenchless methods such as horizontal directional drilling. Submarine cables are also used for HVDC connections. Laying cables is permit-intensive and involves substantial environmental requirements. Modern methods reduce interventions and speed up construction time.
For transmission grid projects – such as large transformers or special components for extra-high voltage – our engineers are your point of contact. Contact us early on.