Mainland France is a single bidding zone, so one day-ahead price applies across the whole country. It is set in an auction that closes at midday for the following day. The forecast covers all 24 hours of tomorrow and is published before that auction closes.
The French day-ahead auction sets one price per hour for the mainland French bidding zone, and it closes at 12:00 CET for the following delivery day. A price forecast is only of use to anyone trading it if it is published before then. Ours is, every morning, for all 24 hours, in euro per megawatt hour.
France is a nuclear market first. Around 63 GW of reactors sit at the base of its supply, the largest nuclear fleet in Europe, so how much of that fleet is available is one of the main things that moves the French price. Reactors come off line in turn for refuelling and maintenance, so the available fleet changes through the year and from one year to the next.
2022 shows what happens when that availability falls. Stress corrosion found in several reactors, on top of scheduled outages, kept a large part of the fleet off line for much of the year. France, normally one of the largest net exporters of electricity in Europe, imported more than it exported over the year for the first time in decades, and the day-ahead price averaged several times its level of three years earlier.
Demand matters here more than in most of Europe. A large share of French homes heat with electricity, so a cold spell pushes demand up quickly and the winter peak sits well above the summer one. At the other end of the day, more than 25 GW of solar now feeds the grid on a bright afternoon, and hours below zero have become a regular midday feature in spring and summer: close to 6 per cent of hours in 2025 cleared below zero.
France also sits at the centre of the continental grid. It is connected to Belgium and Germany inside the flow-based Core region, and to Spain, northern Italy, Switzerland and Great Britain, so the French price often moves with its neighbours' and separates from them when the interconnectors are full.
The auction clears once and the price it sets is final, which is what makes the record on this page possible. Each published forecast is written once and never changed, and the price the auction actually cleared at is placed beside it hour by hour as soon as it settles, including on the days the forecast was wrong. The hours are the CET auction day, which for France is also local time, all year round.
No. It covers the mainland French bidding zone, which is the zone the day-ahead auction clears. Corsica and the overseas territories run separate electricity systems and are not priced in that auction.
Because nuclear is the base of French supply, with around 63 GW of reactors against a demand that sits below that for much of the year. When most of the fleet is running, France exports and its price tends to sit at or below its neighbours'. When a large part of it is off line, for refuelling, maintenance or an unplanned problem, gas, hydro and imports have to cover the gap, and the price rises with them.
Every morning, before the day-ahead auction closes at 12:00 CET, for all 24 hours of the next delivery day, in euro per megawatt hour. The settled price is added to each hour once the auction clears, and the full record stays public.
Because the day-ahead market is an auction rather than continuous trading. It clears once, around midday on the day before delivery, and fixes one price per hour for the whole of the next day. Nothing moves it during the delivery day itself, so each forecast can be placed beside the price it was aiming at the same afternoon.