Baltic Cable
Encyclopedia
The Baltic Cable is a HVDC
power line
running beneath the Baltic Sea
that interconnects the electric power grids of Germany
and Sweden
.
The Baltic Cable uses a transmission voltage of 450 kV
– the highest operating voltage for energy transmission in Germany. The total project cost was 2 billion SEK
(US$280 million), and the link was put into operation in December 1994. With length of 250 kilometres (155.3 mi), it was the second longest high voltage cable on earth, until Basslink
came into service in 2006. It is a monopolar HVDC system with a maximum transmission power of 600 megawatts (MW).
at 53°53′45.8"N 10°48′08.7"E. It crosses the river Trave
in a channel 6 metres (19.7 ft) below the bottom of the river and then follows its course as sea cable laid at the Eastern side of this river. After crossing the peninsula
at Priwall
the cable runs at first parallel to the coast of Mecklenburg-Vorpommern, in order to turn behind Rostock
north-easterly toward Sweden
.
From the point at the southern coast of Sweden where it reaches land, the Baltic-Cable runs a further 5.5 kilometres (3.4 mi) as an underground cable until a point east of the road E6 at 55°25′27"N 13°03′43.3"E, where inside a fenced area the transition from underground cable to overhead powerline takes place. From there the powerline runs as overhead line over two suspension pylons in north-northwesterly direction until the first strainer at 55°25′50.1"N 13°3′12"E. There the line turns into north-northeasterly direction and runs over seven suspension pylons past Södra Häslov to the next strainer at 55°27′8.1"N 13°2′56.2"E. Its track goes now further on 8 suspension pylons in northeasterly direction to the third strainer at 55°28′33.3"N 13°04′02.2"E. The next section consists of 15 suspension pylons from which the third tower situated at 55°28′38.5"N 13°04′49.1"E, the ninth tower situated at 55°28′59.4"N 13°06′15.2"E and the 12th tower situated at 55°29′9.6"N 13°07′12.6"E are angle suspension pylons. It ends at a strainer east of Västra Ingelstad at 55°29′29.7"N 13°8′18.3"E. From this strainer the line runs on one suspension pylons, one angle suspension pylon situated at 55°29′52"N 13°08′33.6"E and the termination tower in northeasterly direction to Kruseberg static inverter plant at 55°30′01.1"N 13°08′45"E. This facility, which is also known as Arrie Static Inverter Plant, is attached to a 400 kV/130 kV substation of the Swedish power grid.
The total count of pylons of the 12.1 kilometres (7.5 mi) long overhead line is 40. All these pylons have a single crossbar, on which two conductors are mounted on 6 metres (19.7 ft) long insulators. Each conductor is a bundle of two ropes with 910 mm² cross section. Both conductors are connected with each other at the ends of the overhead line, so this line is unipolar, although it looks bipolar.
The 23-kilometre-long line to the ground electrode in the Baltic Sea on the Swedish Coast consists of two parallelized XLPE-insulated underground cables with 630 mm² cross section. The electrode itself is designed as anode and consisting of 40 titanium nets each with a surface of 20 m², which are laid on the sea bottom under plastic tubes and stones.
The cathode is situated in the Baltic Sea north of Elmenhorst at 54°1′42"N 11°8′24"E. It consists of a bare copper ring with a 2-kilometre diameter. It is connected to the static inverter plant in Lübeck-Herrenwyk with a 32-kilometre-long XLPE-insulated cable. The first 20 kilometres of this cable have a cross section of 1400 mm² and the last of 800 mm². This cable is laid in the tunnel under Trave River close to the high voltage cable and from then until a point situated at 54°02′00.6"N 11°03′11.5"E in a distance of 2.5 metres to the high voltage cable. By this the magnetic field, which may affect compasses of vessels in this highly frequented area is reduced.
The remaining way to the cathode it runs on a separate way.
As Baltic-Cable is a monopolar line it produces much higher magnetic fields than bipolar cables with the same ratings.
The cable cannot be operated at the maximum transmission rating of 600 megawatts, because the 380 kV line which begins at the converter station of Lübeck-Herrenwyk ends at the Lübeck-Siems substation. This is the only 380 kV powerline in Germany, which has no direct connection to the Central European 380 kV grid, which causes Baltic Cable to use 372 Megawatts (MW) capacity instead of 600 MW. From there power flows on 220 kV and 110 kV lines, which reduces the maximum transmission rate and increases the losses of the transmission.
In the area of the static inverter plant there is also a 110 kV/220 kV sub-station, fed by two 110 kV circuits from the Lübeck-Siems sub-station. There is no transformer for coupling the 380 kV- and the 110 kV-grid in the area of the Lübeck-Herrenwyk static invertor plant.
to Lübeck-Siems and from Schwerin
substation to Lübeck-Herrenwyk), the 380 kV line between Krümmel and Lübeck-Siems was canceled according to speakers from E.ON AG
.
There is still the option to build a 380 kV line from Lübeck to another 380 kV substation in Schleswig-Holstein
, Hamburg
or Lower Saxony
. The construction of the 380 kV link between Lübeck-Herrenwyk and Schwerin is not progressing due to opposition from ecologists.
A transmission rate of 600 MW should be possible via a new 220 kV cable and a static var compensator
in Lübeck-Siems after 2005.
High-voltage direct current
A high-voltage, direct current electric power transmission system uses direct current for the bulk transmission of electrical power, in contrast with the more common alternating current systems. For long-distance transmission, HVDC systems may be less expensive and suffer lower electrical losses...
power line
Electric power transmission
Electric-power transmission is the bulk transfer of electrical energy, from generating power plants to Electrical substations located near demand centers...
running beneath the Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
that interconnects the electric power grids of Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
and Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
.
The Baltic Cable uses a transmission voltage of 450 kV
Volt
The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
– the highest operating voltage for energy transmission in Germany. The total project cost was 2 billion SEK
Swedish krona
The krona has been the currency of Sweden since 1873. Both the ISO code "SEK" and currency sign "kr" are in common use; the former precedes or follows the value, the latter usually follows it, but especially in the past, it sometimes preceded the value...
(US$280 million), and the link was put into operation in December 1994. With length of 250 kilometres (155.3 mi), it was the second longest high voltage cable on earth, until Basslink
Basslink
Basslink is a high-voltage direct current cable link crossing Bass Strait, connecting the Loy Yang Power Station, Victoria on the Australian mainland to the George Town substation in northern Tasmania...
came into service in 2006. It is a monopolar HVDC system with a maximum transmission power of 600 megawatts (MW).
Route
The course of the Baltic Cable starts in Germany at the inverter station at Lübeck-Herrenwyk, which is on the site of a former coal-fired power stationPower station
A power station is an industrial facility for the generation of electric energy....
at 53°53′45.8"N 10°48′08.7"E. It crosses the river Trave
Trave
The Trave is a river in Schleswig-Holstein, Germany. It is approximately 124 kilometres long, running from its source near the village of Gießelrade in Ostholstein to Travemünde where it flows into the Baltic Sea. It passes through Bad Segeberg, Bad Oldesloe, and Lübeck, where it is linked to the...
in a channel 6 metres (19.7 ft) below the bottom of the river and then follows its course as sea cable laid at the Eastern side of this river. After crossing the peninsula
Peninsula
A peninsula is a piece of land that is bordered by water on three sides but connected to mainland. In many Germanic and Celtic languages and also in Baltic, Slavic and Hungarian, peninsulas are called "half-islands"....
at Priwall
Priwall
Priwall may refer to* Priwall Peninsula, in Germany* Priwall , a German Flying P-Liner sailing ship...
the cable runs at first parallel to the coast of Mecklenburg-Vorpommern, in order to turn behind Rostock
Rostock
Rostock -Early history:In the 11th century Polabian Slavs founded a settlement at the Warnow river called Roztoc ; the name Rostock is derived from that designation. The Danish king Valdemar I set the town aflame in 1161.Afterwards the place was settled by German traders...
north-easterly toward Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
.
From the point at the southern coast of Sweden where it reaches land, the Baltic-Cable runs a further 5.5 kilometres (3.4 mi) as an underground cable until a point east of the road E6 at 55°25′27"N 13°03′43.3"E, where inside a fenced area the transition from underground cable to overhead powerline takes place. From there the powerline runs as overhead line over two suspension pylons in north-northwesterly direction until the first strainer at 55°25′50.1"N 13°3′12"E. There the line turns into north-northeasterly direction and runs over seven suspension pylons past Södra Häslov to the next strainer at 55°27′8.1"N 13°2′56.2"E. Its track goes now further on 8 suspension pylons in northeasterly direction to the third strainer at 55°28′33.3"N 13°04′02.2"E. The next section consists of 15 suspension pylons from which the third tower situated at 55°28′38.5"N 13°04′49.1"E, the ninth tower situated at 55°28′59.4"N 13°06′15.2"E and the 12th tower situated at 55°29′9.6"N 13°07′12.6"E are angle suspension pylons. It ends at a strainer east of Västra Ingelstad at 55°29′29.7"N 13°8′18.3"E. From this strainer the line runs on one suspension pylons, one angle suspension pylon situated at 55°29′52"N 13°08′33.6"E and the termination tower in northeasterly direction to Kruseberg static inverter plant at 55°30′01.1"N 13°08′45"E. This facility, which is also known as Arrie Static Inverter Plant, is attached to a 400 kV/130 kV substation of the Swedish power grid.
The total count of pylons of the 12.1 kilometres (7.5 mi) long overhead line is 40. All these pylons have a single crossbar, on which two conductors are mounted on 6 metres (19.7 ft) long insulators. Each conductor is a bundle of two ropes with 910 mm² cross section. Both conductors are connected with each other at the ends of the overhead line, so this line is unipolar, although it looks bipolar.
The 23-kilometre-long line to the ground electrode in the Baltic Sea on the Swedish Coast consists of two parallelized XLPE-insulated underground cables with 630 mm² cross section. The electrode itself is designed as anode and consisting of 40 titanium nets each with a surface of 20 m², which are laid on the sea bottom under plastic tubes and stones.
The cathode is situated in the Baltic Sea north of Elmenhorst at 54°1′42"N 11°8′24"E. It consists of a bare copper ring with a 2-kilometre diameter. It is connected to the static inverter plant in Lübeck-Herrenwyk with a 32-kilometre-long XLPE-insulated cable. The first 20 kilometres of this cable have a cross section of 1400 mm² and the last of 800 mm². This cable is laid in the tunnel under Trave River close to the high voltage cable and from then until a point situated at 54°02′00.6"N 11°03′11.5"E in a distance of 2.5 metres to the high voltage cable. By this the magnetic field, which may affect compasses of vessels in this highly frequented area is reduced.
The remaining way to the cathode it runs on a separate way.
As Baltic-Cable is a monopolar line it produces much higher magnetic fields than bipolar cables with the same ratings.
Operation
Because this overhead line can generate radio interference, there is a highly effective active filter system installed at the Kruseberg inverter station. In the Lübeck-Herrenwyk inverter station, there is no requirement for such a system, because there is no overhead powerline section on the German side.The cable cannot be operated at the maximum transmission rating of 600 megawatts, because the 380 kV line which begins at the converter station of Lübeck-Herrenwyk ends at the Lübeck-Siems substation. This is the only 380 kV powerline in Germany, which has no direct connection to the Central European 380 kV grid, which causes Baltic Cable to use 372 Megawatts (MW) capacity instead of 600 MW. From there power flows on 220 kV and 110 kV lines, which reduces the maximum transmission rate and increases the losses of the transmission.
In the area of the static inverter plant there is also a 110 kV/220 kV sub-station, fed by two 110 kV circuits from the Lübeck-Siems sub-station. There is no transformer for coupling the 380 kV- and the 110 kV-grid in the area of the Lübeck-Herrenwyk static invertor plant.
Expansion schemes
Of the two originally planned 380 kV lines to Lübeck (from Krümmel Nuclear Power PlantKrümmel Nuclear Power Plant
Krümmel Nuclear Power Plant is a nuclear power plant in Geesthacht near Hamburg, Germany. It was taken into operation in 1983 and is owned 50% by Vattenfall via Vattenfall Europe Nuclear Energy GmbH and 50% by E.ON, and operated by the Swedish Vattenfall...
to Lübeck-Siems and from Schwerin
Schwerin
Schwerin is the capital and second-largest city of the northern German state of Mecklenburg-Vorpommern. The population, as of end of 2009, was 95,041.-History:...
substation to Lübeck-Herrenwyk), the 380 kV line between Krümmel and Lübeck-Siems was canceled according to speakers from E.ON AG
E.ON
E.ON AG, marketed with an interpunct as E•ON, is the holding company of the world's largest investor-owned energy service provider based in Düsseldorf, Germany. The name comes from the Greek word aeon which means eternity....
.
There is still the option to build a 380 kV line from Lübeck to another 380 kV substation in Schleswig-Holstein
Schleswig-Holstein
Schleswig-Holstein is the northernmost of the sixteen states of Germany, comprising most of the historical duchy of Holstein and the southern part of the former Duchy of Schleswig...
, Hamburg
Hamburg
-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...
or Lower Saxony
Lower Saxony
Lower Saxony is a German state situated in north-western Germany and is second in area and fourth in population among the sixteen states of Germany...
. The construction of the 380 kV link between Lübeck-Herrenwyk and Schwerin is not progressing due to opposition from ecologists.
A transmission rate of 600 MW should be possible via a new 220 kV cable and a static var compensator
Static VAr compensator
A static var compensator is an electrical device for providing fast-acting reactive power on high-voltage electricity transmission networks. SVCs are part of the Flexible AC transmission system device family, regulating voltage and stabilising the system...
in Lübeck-Siems after 2005.
Sites
| Site | Coordinates |
|---|---|
| Kruseberg HVDC Static Inverter | 55°30′01.1"N 13°08′45"E |
| Västra Värlinge Cable Terminal (Sweden) | 55°25′27"N 13°03′43.3"E |
| Herrenwyk HVDC Static Inverter | 53°53′45.8"N 10°48′08.7"E |
External links
- Baltic Cable AB website
- Baltic Cable HVDC project (ABB website)
- http://web.archive.org/web/20051115122606/www.transmission.bpa.gov/cigresc14/Compendium/BALTIC.htm
- http://web.archive.org/web/20051115122606/www.transmission.bpa.gov/cigresc14/Compendium/Baltic%20Pictures.pdf
- http://www.fiveoceansservices.com/content/projects/powerCables/BalticCableProject/index.html