SEPS completes first stage of V440 line to Ukraine: 6.67 km rebuilt as the 400 kV line becomes double-circuit

Slovenská elektrizačná prenosová sústava (SEPS), Slovakia's transmission system operator, announced on 5 November that it has completed the first stage of modernising the 400 kV V440 line, which runs from the Veľké Kapušany substation to the border with Ukraine. The work, which began in May 2026, replaced towers along a 6.67 km section.

What changes. According to SEPS, the line is going from a single 400 kV circuit to two (2×400 kV), increasing the reliability and transfer capacity of the interconnector; the operator did not give a figure for the new capacity. The work follows the original route and axis without widening the protection zone, and the new barrel-type (súdok) towers will narrow it.

The timetable. The full reconstruction covers 12.447 km in two stages and is being carried out with the Ukrainian transmission system operator. The remaining 5.78 km is planned for the second quarter of 2027, SEPS spokesperson Sandra Čičová Kotzigová said, as quoted by the TASR news agency.

Context. V440 has been in service since 1963 and is one of the oldest lines in the Slovak grid; SEPS says it is reaching the end of its technical life. According to a SEPS spokesperson quoted in 2024 by Energie-portal.sk, the V440 Veľké Kapušany–Mukachevo line was then the only 400 kV link between Slovakia and Ukraine. SEPS operates 2,366 km of 400 kV lines, 652 km of 220 kV lines and 22 substations, according to SITA. The company is wholly owned by the Slovak state through the Ministry of Finance and is a member of ENTSO-E.

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