Synchronous grid of Continental Europe

The predecessor of the UCTE was founded on May 23, 1951 in Paris at the suggestion of the OEEC aka Union pour la coordination de la production de l’Electricité et du transport (UCPTE).  In 1999 the UCPTE was converted to the UCTE due to the liberalization of the electricity market. The network of UCTE is, like all electric power grids, a three-phase current high voltage grid.

The founder members of UCPTE in 1951 were: Belgium, Germany, France, Italy, Luxembourg, Netherlands, Austria, Switzerland. In 1987 the interconnected system of UCPTE was expanded to include four new countries: Greece, Yugoslavia, Spain, Portugal. Due to the connection to the Eastern European systems in 1995 the Czech Republic, Slovakia, Poland and Hungary became also members of UCPTE.

Since 2009, the organizational and administrative tasks has been taken over by  the European Network of Transmission System Operators for Electricity (ENTSO-E), which comprises different interconnected systems. The technical limitations of interconnections and the former UCTE however remained unchanged. Thats why  the former UCTE and the Scandinavian countries are still not directly connected electrically in the interconnected system of Nordel. Although the interconnections have the mains frequency of 50 Hz, the same nominal value, but specific deviations and phase angles of the line frequency are still different, so the networks are asynchronous to each other. Electrical energy between these grids can only be transmitted in the form of direct current on high-voltage direct current.


Regional structure

ENTSO-E is divided into five regional groups and 2 voluntary Regional Groups (Northern Europe and Isolated Systems), which derive from the historic background of the former associations.

Continental Europe

The regional group of Continental Europe includes the former members of the Union for the Co-ordination of Transmission of Electricity(UCTE).


The region of Ireland consists of EirGrid and System Operator for Northern Ireland (SONI), the former members of the Association of the Transmission System Operators of Ireland (ATSOI).

United Kingdom

The region of the United Kingdom consists of the TSOs of the United Kingdom, former members of the UK Transmission System Operators Association (UKTSOA).


The Nordic region consists of Finland, Sweden, Norway and Eastern Denmark, the former members of the Nordic TSO association NORDEL. NORDEL was founded in 1963 for co-operation between the TSOs of Denmark, Finland, Iceland, Norway and Sweden for a further development of an harmonized Nordic electricity market.


The Baltic region consists of Estonia, Latvia and Lithuania. Before creation of the ENTSO-E, the Baltic TSOs were members of the Baltic Transmission System Operators association (BALTSO). BALTSO was founded on 30 March 2006.

Main Task of ENTSOE

  • Elaboration and establishment of network codes
  • Ensure coordination of network operation by common network operation tools
  • Develop a ten-year network development plan
  • Publish annual work programme, annual report and annual summer and winter generation adequacy outlooks

Nevertheless changes in the frequency may occur if supply or demand exceeds its counterpart. In case of too much supply the frequency will increase, while in case of too much demand it will decrease. The main task is to keep the frequencies of all five synchronous areas balanced around the 50 hertz standard to ensure a safe power supply.

Check the current frequency of Continental Europe.