Despite the increase in power production from renewables, Greece remains consistently among the most expensive countries in Europe in the wholesale electricity market, a condition that environmental think tank the Green Tank attributes to the high dependence of the Greek market on natural gas and the limited development of energy storage.
Renewable energy sources (RES) push prices down during the midday hours, when their production is high. On the contrary, at night, when RES production decreases and the participation of natural gas grows, prices rise significantly.
The difference between the average minimum price of the day and the average maximum recorded when demand peaks at night increased from 128 euros/megawatt-hour in 2024 to €143.4/MWh in 2025.
The widening of the gap, according to the Green Tank, is associated with the simultaneous increase in RES and natural gas production. In the first months of 2025, RES increased by 5.5% from the same period in 2024; however, the increase in natural gas was even greater (12.6%), while part of this increased production was channeled into exports.
RES are lowering prices, but their effect on the reduction is less than the effect of natural gas on the increase in prices, according to the Green Tank analysis titled “What Is Causing High Electricity Prices?” – an issue that the Competition Commission is also investigating recently following the findings of European regulator ACER about possible indications of market manipulation.
The Green Tank drew on real-time data collected daily by the European Network of Transmission System Operators for Electricity (ENTSO-E), and highlights the main factors influencing prices in the wholesale electricity market. Greece’s case is compared with Portugal – a country with similar characteristics but consistently lower prices in the Day Ahead Market (DAM).
According to its analysis, until the start of Russia’s invasion of Ukraine, the two countries were practically in line with each other in terms of electricity prices. In the period after Russia’s invasion, Greece was on average 36% more expensive than Portugal, while in April 2024 this difference peaked at 78%. Large differences are also observed in price fluctuation, where for the period from 2023 to date the difference between the maximum and minimum monthly price in Greece was many times that in Portugal.