Power grid main characteristics
In France, the high and extra-high voltage electricity transmission network, operated by RTE, comprises 100,000 kilometres of power lines (from 63,000 up to 400,000 volts). Two main physical characteristics may be remembered :
The country’s central geographical position in Europe gives the French network its main characteristics. The network is interconnectedwith the neighbouring countries (Great Britain, Belgium, Germany, Italy, Switzerland and Spain). It is the largest grid in Europe. With 46 cross-border lines, France is able to import up to 9000 MW and export 12000 MW. Electricity may be exchanged to provide mutual backup as needed. Theses wide exchanges at the heart of the European electrical system are a big advantage for the security of supply of the country.
France’s transmission network is meshed across the entire territory for a better security of supply. The meshed network means that, any time a power line is out of service, there are always other power lines for electricity always to find its way to reach consumption zones.
Major incidents & preventive measures
The main European electrical shortage
On November 4th 2006, Europe experienced a huge power shortage following a network incident in Germany. One of the German transmission system operators switched off the 400,000 volt power line that crosses the River Ems in the north of the country, to allow a ship to pass through. Electricity transmission flows were instantly redistributed on the remaining lines. Becoming saturated, those lines tripped in what is known as a “cascade”. Many power lines in Germany, Austria, Hungary and Croatia were automatically disconnected. Ultimately, the entire European continent was affected: altogether, some 15 million homes were without power for one hour maximum.Since that incident, Europe’s transmission system operators have taken a number of measures. They have strengthened their technical cooperation. And, in 2008, they created a European grid coordination centre in Bruxelles (Coreso) which provides constant analysis of system security and monitors Europe’s power networks to prevent electrical disturbances.
Storms Lothar and Martin, on December 1999, were historically exceptional. They swept the whole country and affected severely the French power grid.In the wake of the storms, RTE embarked on a programme designed to physically secure the network, with the aim of ensuring that power could be restored within five days in the event of another severe climatic event. The programme is carried out over a fifteen year period, running through to 2017.
Storms Klaus of January 2009 and Xynthia of February 2010 confirmed the effectiveness of the work carried out to secure the network. The work will be completed by 2017, for a total cost of 2.4 billion euros over 15 years.