How the network evolved in 2019
  • Length of lines
  • Substation connections

    Length of lines

    RTE is the largest transmission system operator in Europe with 105,942 km of lines in service. As the operator of the French power system, its mission is to offer customers access to an affordable, safe, clean electricity supply today and tomorrow. This notably requires investing steadily to build a transmission network that can support the economy and energies of the future.

    Highlights of 2019 included:

    New underground cables (newly created or overhead lines newly undergrounded) totalled 219 km, while 477 km of overhead lines were taken down (permanently or to be replaced) during the year.

    The length of the network increased by 85 km year-on-year in 2019.


    Length of lines in service (km) Overhead Underground Total
    At 31 December 2018 99 655 6 202 105 857
    New 401 232 633
    Newly added
    38 160 198
    Replaces 363 13 376
    Overhead lines burried
    0 59 59
    Scrapped -477 -7 -484
    Other (placed in reserved, length adjusted, etc.) -52 -12 -64
    At 31 December 2019 99 527 6 415 105 942
    Change 2018 to 2019 -128 213 85


    Closer look

    Better understanding

    The total length of overhead lines on the transmission network continued to decrease, falling to 99,527 km.

    The total length of underground lines in service rose further, to 6,415 km.

    Closer look

    Better understanding

    Substation connections

    Along with power lines, substations play an important role in keeping the grid operating smoothly as they receive electrical energy and then transform and distribute it. They too require continued investment.

    Sixteen new substations were connected to the transmission system in 2019, including nine that are 225 kV.

    Two inaugurations were particularly worthy of note:

    • Montgros, 225 kV, in Lozère (to improve quality of supply in that department and to support the energy transition);
    • Saverdun, 63 kV, in Ariège (to increase the region’s power of attraction with the connection of an SNCF traction substation).

    Closer look

    Better understanding