Dim lights or blackouts?

If you felt a bit dim in December and again in mid-January, it probably wasn't your fault. In fact during those two periods of unseasonably low temperatures (7-8°C below the normal) EDF turned down the power. As a consequence of the wave of very cold air that passed over France, the demand for electricity increased and very nearly exceeded the capability of the network to satisfy the requirement. In order to avoid blackouts, the power output was reduced by 5%. On the evenings of the 6th and 7th of January, the consumption of electricity reached 91 000 MW, according to Réseau de Transport d'Electricité (RTE). They estimated that on the 11th, 12th and 13th of January the demand would set a new historic record, beating the 92 400MW consumed on 7 January 2009, but in fact the weather warmed slightly and demand fell back.

France is normally self-sufficient in electricity, generating 80% of its electricity requirement through the use of 58 nuclear reactors. By 2020 this will have increased to 60 when the new reactors at Flamanville and Penly become operational. Unfortunately, in early January, nine of the existing reactors were stopped for technical reasons, leaving the network under capacity. The configuration of the network means that France has the option to buy in up 9 000 MW of electricity from its European neighbours and on the 4th of January it imported 2 400 MW and 4 800 MW on the 5th and 6th. In mid-december, the importation exceeded 6 600 MW, which is the equivalent of 6 nuclear reactors. France's electricity generation has been called all-nuclear because of the almost exclusive use of nuclear reactors and therefore the electricity is low impact when it comes to greenhouse gas emissions, but the reactors are slow to respond to demand. Whilst improvements in the structure to allow greater levels of importation and improved levels of reactor availability will reduce the risk of shortfalls, the construction of 12 gas-fired generating plants to meet short-term demand, has been proposed by the Direction Générale de l'Energie et du Climat. In Germany, the majority of homes are heated by gas or oil and a drop in temperature there brings about a large increase in CO2 emissions. By comparison, in France, many households are equipped with electric heating and as a result a drop in temperature of 1°C will increase electricity demand by 2 100 MW, but the environmental impact is low.