Greece electricity price prediction for tomorrow

Forecasting the Greek electricity price

Greece is a single bidding zone, so one day-ahead price applies across the whole interconnected system. OpenWindCast forecasts all 24 hours of tomorrow's delivery day, using only information available before the auction closes.

The Greek day-ahead auction sets one price per hour for the Greek bidding zone, and it closes at 12:00 Central European Time for the following delivery day. Every forecast here uses only information that was available before then, and covers all 24 hours, in euro per megawatt hour.

Greece is a market whose day has two different halves. Gas sets the price in the evening: over the three months to September 2026 gas plants produced close to two fifths of Greek electricity, and the lignite fleet that used to sit under them has shrunk from about 3.4 GW of capacity in 2020 to about 1.5 GW in 2026 as it is phased out. Solar sets the price in the middle of the day: the fleet has grown from roughly 2.6 GW in 2020 to roughly 9.8 GW in 2026 and produced close to a third of Greek electricity over those same three months. The result is a price that moves more within the day than from one day to the next. Over the past year more than three quarters of all its variation came from the difference between hours of the same day.

That midday solar surplus has arrived quickly and it shows up as cheap and negative hours. Around one hour in a thousand cleared below zero in 2024, a little over one in a hundred in 2025, and about seven in a hundred so far in 2026. They are not spread through the day: in the past year no hour between 17:00 and 07:00 cleared below zero, while around one in five of the hours between 09:00 and 14:00 did. About one 2026 hour in six has cleared below 10 euro per megawatt hour, and about one in fifteen at exactly zero, which is the point at which renewable output starts being curtailed instead.

The Greek price is also a regional one. Greece is coupled to Bulgaria and to southern Italy, and over the past year it cleared at exactly the Bulgarian price in around 62 per cent of hours. The other 38 per cent are the hours when the border between them is full, and on those Greece is usually the cheaper side, by around 11 euro per megawatt hour on average, because a midday surplus that cannot be exported has to be absorbed at home. Coupled prices meet when the borders have room to spare and separate when they do not, so this remains the Greek zone's own price.

The market itself is recent. The current day-ahead auction opened on 1 November 2020, when Greece moved to the European target model, with coupling to Italy following in December 2020 and to Bulgaria in May 2021. The forecast and the record here are about that market: the interconnected system, which since 2021 includes Crete. The smaller non-interconnected island systems are operated separately and sit outside the day-ahead market.

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.

One detail worth knowing when reading the table. The hours shown are the CET auction day, because that is the day the market trades and prices. Greek local time is an hour ahead of CET all year round, so the delivery day on this page begins at 01:00 in Athens, and its final hour has already crossed into the next Greek calendar day.

The price forecast and the Greek wind forecast are separate products, scored separately, and each has its own record on this page.