Czech transmission and distribution system – Part 2: Transmission system substations

The miniseries on the Czech transmission and distribution system continues. In the previous instalment, you could learn about the electrification of the Czech Republic and the basic operation of the transmission and distribution system. Today’s instalment will focus on one of the most important parts of the Czech transmission system: substations.

The transmission system, which is operated in the Czech Republic by ČEPS, consists of two main parts: substations and the lines connecting them. The lines operate at three voltage levels: 400 kV (EHV – extra-high voltage), 220 kV and 110 kV (both HV – high voltage). The exact lengths of lines in the Czech Republic are as follows:

• 400 kV (designated V4xx) – 3 735 km (of which double-circuit and multi-circuit lines account for 1 371km)
• 220 kV (designated V2xx) – 1 909 km (of which double-circuit and multi-circuit lines account for 1 038km)
• 110 kV (designated Vxxxx) – 84 km (of which double-circuit and multi-circuit lines account for 78 km)

The Czech transmission system is interconnected with neighbouring countries by 11 400 kV lines and 6 220 kV lines.

These three voltage levels also have corresponding substations, of which there are 43 in total. Transformation is provided by 78 transformers with a combined transformation capacity of 22 450 MVA. This capacity is divided among 4 transformers rated at 400/220 kV, 49 transformers rated at 400/110 kV and 21 transformers rated at 220/110 kV. In addition, 4 phase-shifting transformers (PSTs) with a transformation capacity of 3 400 MVA at 400/400 kV are in operation.

The ability to provide reactive power is essential for operating the transmission system. This is supplied by 22 shunt reactors with a total reactive power capacity of 1 518,6 MVAr.

Below is a list of the most significant substations, divided according to the voltage level at which they currently operate in the transmission system, along with brief information including connected lines, year of construction, location and other details.

All data in this article are current as of September 2019, unless stated otherwise.

400 kV substations

• Nošovice (Station designation: NOS, commissioned: 1959, district: Frýdek – Místek)
  • V403, V404, V405, V444 and V460
  • At the time of its construction, there were only 220 kV lines here, but all were gradually converted to 400 kV.
  • Lines V404 and V444 are cross-border lines; V404 leads to Slovakia and V444 to Poland.

• Krasíkov (KRA, 1969, Ústí nad Orlicí)
  • V401, V402, V453, V457 and V458
  • By its construction, the substation divided the original line from Výškov to Prosenice.
  • The Dlouhé Stráně pumped-storage hydropower plant (V457) was connected to this substation in 1993.
  • Construction of the new V458 line, linking the Krasíkov substation with the Horní Životice substation, was completed in 2016.

• Albrechtice (ALB, 1970, Karviná)
  • V443 and V460
  • Line V443 is a cross-border line leading to Poland.

• Čebín (CEB, 1974, Brno – venkov)
  • V422, V434 and V423
  • The substation was built on the route of the original line between Hradec and Sokolnice.
  • The substation underwent a complete reconstruction between 2013 and 2015.

• Řeporyje (REP, 1975, Capital City of Prague)
  • V412, V413 , V475 and V414
  • With its construction, the substation divided the line from Hradec to Prosenice into V412 and V413.

• Týnec (TYN, 1977, Kolín)
  • V400, V401 and V471/472
  • Output from the Chvaletice power plant (V471/472) is fed into the Týnec substation, which was built for the plant and thereby divided the original line from the Čechy Střed substation to Krasíkov.

• Otrokovice (OTR, 1977, Zlín)
  • V417 and V418
  • The original line between the Sokolnice and Prosenice substations was divided into lines V417 and V418 by the construction of this substation.

• Slavětice (SLV, 1977, Třebíč)
  • V433, V434, V435/436, V437/438, V481/482, V483, V484, V485 and V486
  • The substation was commissioned together with the Dalešice pumped-storage hydropower plant (V481/2), and the Dukovany nuclear power plant (V483, V484, V485 and V486) was connected to it in 1985.
  • Line V437/438 is a cross-border line leading to Austria.

• Babylon (BAB, 1980, Česká Lípa)
  • V450, V451 and V470
  • The substation was built due to the need to connect the Mělník power plant (V470).
  • Interestingly, from 1980 until 2013, when reconstruction began, it was equipped with a British-made transformer (Hawker Siddeley), which was an exception during the Iron Curtain era, as most transformers were Soviet-made or domestically manufactured.

• Neznášov (NEZ, 1980, Náchod)
  • V452 and V453
  • Together with the Babylon substation, it divided the original line from Výškov to Krasíkov into three separate sections.

• Chrást (CHR, 1981, Plzeň – město)
  • V430 and V431
  • Its construction brought power from the Hradec substation to the Plzeň Region at the 400 kV level.

• Dasný (DAS, 1981, České Budějovice)
  • V473, V474 and V433
  • V1344/1345
  • The construction of this substation enabled power to be brought from northern Bohemia to southern Bohemia via the Chrást substation on a 400 kV line.

• Mírovka (HBM, 1982, Havlíčkův Brod)
  • V413, V416, V420 and V422
  • Its construction divided the line from Hradec to Čebín.
  • A comprehensive reconstruction took place between 2012 and 2015.
  • In 2019, a loop was constructed from line V413, dividing it into V413 (Řeporyje – Mírovka) and V416 (Mírovka – Prosenice).

• Horní Životice (HZI, 1987, Bruntál)
  • V459 and V458
  • Construction of the new V458 line from the Krasíkov substation was completed in 2016.

• Chodov (CHD, 1993, Capital City of Prague)
  • V414, V415 and V476
  • The substation was built in connection with construction of the Temelín nuclear power plant, and it supplies power to the Prague metropolitan area (together with the Řeporyje substation).

• Kočín (KOC, 1994, České Budějovice)
  • V051, V052, V432, V473, V474 and V475/476
  • V1344/1345 and V1346/1347
  • The Temelín nuclear power plant, for which the substation was built, is located nearby and connected to it (V051 and V052), along with the Hněvkovice hydropower plant (V1346/1347).

• Kletné (KLT, 2012, Nový Jíčín)
  • V405 and V459
  • The substation was built in coordination with ČEZ Distribuce.
  • It divided the original V459 line into two separate lines.

• Vernéřov (VER, 2017, Chomutov)
  • V461
  • The substation was built in response to the distribution operator’s requirement for new transformation capacity in the area.

400 kV and 220 kV substations

• Výškov (VYS, 1951, Louny)
  •  V410/419, V411, V450, V467, V468, V469 and V480
  • V201, V225, V226V and V211
  • One of the two oldest substations, built together with the Opočínek substation.
  • The Počerady power plant is connected to the power system here (V467, V468 and V469).
  • In 2016, line V410 was doubled, creating the double-circuit V410/419 line.

• Sokolnice (SOK, 1952, Brno – venkov)
  • V417, V423, V424, V435/436 and V497
  • V203, V207, V243/244, V251/252 and V280
  • One of the first substations in Moravia (along with Prosenice and Lískovec).
  • The substation with the highest number of connected lines in Moravia.
  • Lines V424, V497 and V280 are cross-border lines leading to Slovakia.
  • Line V243/244 is also cross-border, but leads to Austria.

• Prosenice (PRN, 1952, Přerov)
  • V402, V403, V416 and V418
  • V251/252 and V253/254
  • One of the first substations in Moravia (along with Sokolnice and Lískovec).
  • The first 400 kV line ran from the Hradec substation to the Prosenice substation.

• Hradec (HRA/HRD, 1959, Chomutov)
  • a) HRA
    • V411, V412, V461, V462, V441 and V463/464
    • V223/224 and V225/226H
  • b) HRD
    • V420, V430, V445/V446 and V465/V466
  • Output from two coal-fired power plants, Prunéřov (V462, V465 and V466) and Tušimice (V463 and V464), is fed into the Hradec u Kadaně substation.
  • In 2004, this substation was divided into two independent sections (HRA and HRD).
  • In 2017, phase-shifting transformers (PSTs) were commissioned.
  • Lines V445/446 and V441 are cross-border lines leading to Germany.

• Čechy – Střed (CST, 1960, Praha – Východ)
  • V400, V410/419, V415 and V454
  • V201, V202, V205/206, V208 and 209
  • By its construction, the substation divided the historically first transmission system line between Výškov and Opočínek.
  • In 2016, line V410 was doubled, creating the double-circuit V410/419 line.

• Přeštice (PRE, 1963, Plzeň – Jih)
  • V431/432 and V442
  • V216
  • The first substation built in the territory of today’s Plzeň Region.
  • The V221/222 line to the Vítkov substation is being converted to the 400 kV voltage level.
  • Line V442 is a cross-border line leading to Germany.

• Bezděčín (BEZ, 1964, Jablonec nad Nisou)
  • V451, V452 and V454
  • V 209 and V210

• Chotějovice (CHT, 1965, Teplice)
  • V480 and V016
  • V210 and 211
  • The Ledvice power plant is connected to this substation by line V016.
  • Since 2011, it has housed an SF6 gas-insulated substation, built in connection with construction of the new supercritical unit at the Ledvice coal-fired power plant.

220 kV substations

• Opočínek (OPO, 1951, Pardubice district)
  • V202 and V203
  • One of the two oldest substations, built together with the Výškov substation.
  • No new transmission system line has been brought to this substation since its construction.

• Lískovec (LIS, 1952, Frýdek – Místek)
  • V245, V246, V253/254 and V270
  • The first transmission system line into the territory of present-day Slovakia ran from this substation.
  • Line V270 leads to Slovakia.

• Vítkov (VIT, 1960, Sokolov)
  • V011, V017/018  and V223/224
  • Output from the Tisová (V011) and Vřesová (V017/018) power plants is fed into this substation, which was built in the Sokolov coal basin.
  • The V221/222 line to the Přeštice substation is being converted to the 400 kV voltage level, alongside construction of a new 420 kV substation in this area.

• Milín (MIL, 1960, Příbram)
  • V001, V002, V204, V208 and V216
  • Its establishment is closely linked to the Orlík hydropower plant, which is connected to this substation (V001 and V002).

• Malešice (MAL, 1967, Capital City of Prague, Central)
  • V205/206

• Tábor (TAB, 1973, Tábor)
  • V204 and V207
  • Its construction divided the original line between the Milín and Sokolnice substations.

That concludes the overview of transmission system substations. Next time, you can look forward to an equally detailed instalment, this time on transmission system lines.