European Heat Wave Threatens to Spur Record Cooling Demand
(Bloomberg) -- Western Europe is baking under a heat wave that threatens to drive record cooling demand, just as warming rivers force French nuclear reactors to curb output.
The heat wave is forecast to push temperatures 5C to 12C above normal in France, Germany, Italy, Spain and southern England, which could raise cooling demand to the highest level in records going back 45 years, according to analysis from Vaisala meteorologist Matthew Dross.
The unusual heat is driven by a dome of high pressure that raises temperatures as it compresses air toward the ground and clears away clouds. Daytime highs could reach above 40C (104F) by Sunday in Paris and other regions, according to forecaster Météo-France.
The most intense heat is forecast for France, where authorities have issued amber weather alerts across 26 departments. That includes Paris and much of the central and eastern parts of the country, where grain fields are almost ready for harvest.
Météo-France warned that the heat wave coincides with the annual Fete de la Musique on June 21, when concerts and street parties are held across the country. Schools across Paris and other regions have announced that classes will be suspended in the afternoon on Thursday and Friday because of the heat wave, according to Agence France-Presse.
The unusually long-lasting heat wave threatens to curb nuclear output from plants cooled by the Rhône and Garonne rivers, including Saint-Alban, where Electricité de France SA is preparing to limit generation from Saturday. EDF warned that its Blayais and Golfech facilities may also be impacted from June 23 and June 25, respectively.
French nuclear output is closely watched by power markets since the country’s reactor fleet is the backbone of Europe’s electricity system. Restrictions can tighten supplies and lift prices across the region.
French power demand rose on Thursday to about 52.4 gigawatts, the highest level since April 14, according to data from RTE.
To reduce the risk of air-conditioning failures during the heat wave, French transport company SNCF has canceled more than 70 train services on Thursday and Friday, including 14 Paris–Limoges–Toulouse trains, according to France Info.
The heat wave is likely to further dry soils, which have already been depleted by low rainfall in June and a similar heat wave in late May, said Météo-France. Some areas are approaching record-low moisture levels for the season over the coming days.
The combination of dry vegetation and hot weather with low humidity has raised wildfire risks in France and Spain.
Heat wave conditions are also forecast for Germany and are likely to spread into southern England over the weekend, according to the UK Met Office. Temperatures could reach 33C in some areas, with 31C possible in London on Monday and Tuesday. Amber heat health alerts are in place for London and southern England.
Amber heat warnings have also been issued for Switzerland, with a red alert for the northern region around the city of Basel. There are amber warnings in Italy and Spain, along with yellow alerts for Austria, Belgium, Germany and the Netherlands.
(Updates nuclear generation restrictions in sixth paragraph)
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