The Greek electric system successfully passed the Easter 2026 test, despite a low demand and high output coincidence from RES that created a surplus of up to 3-4 GW. There was the preparation with a meeting on Great Wednesday under the ministers of S. Papastavrou and N. Tsafos, as well as daily monitoring through teleconferences. IPTO used exports, RES teleregulation and pumping units, while storage systems were first used. The HEDNO achieved impressive progress, increasing remote-controlled stations from 1,638 (2.286 MW) in 2025 to 6,200 (5.4 GW) in 2026, reducing network interventions from 14 to 7 days.
Analyticalally:
In one of the most demanding periods for the operation of the electricity system, due to the coincidence of low demand and high production from Renewable Energy Sources (RES), the Greek electricity market successfully passed the Easter test. This year's scene was characterized by an intense surplus of production, which in some hours touched 3-4 GW, creating balance pressures in the system.
However, thanks to the technological upgrading of networks, the gradual maturation of the market, but also to the coordination of competent bodies, challenges have been met without problems for the security of supply or stability of the system.
A defining role in the successful management of the period was played by the preparation that preceded. On Wednesday, a meeting was held under the Minister of Environment and Energy S. Papastavrou and Deputy Minister N. Tsafos with the participation of managers and regulators in order to assess operational readiness.
A daily follow-up to the situation through teleconferences throughout the holidays, allowing direct decision-making and adaptation of real-time operations.
The "weapon" of exports and cuts
The main problem that was called upon to manage the system was oversupply of energy from RES in reduced consumption conditions. The IPTO used a range of tools to maintain balance:
• Electricity exports, absorbing some of the surplus
• RES production monitoring by the Energy Control Centre
• Use of hydroelectric pump units for energy storage
At the same time, the contribution of the market itself was important. Many RES producers, through the Cumulative Representation Agencies (FOSE), proceeded to self-injection interruption when prices on the earlier market of the Energy Exchange became zero or negative. This phenomenon demonstrates the increasing adaptation of participants to new market data.
First test for batteries
Of particular importance is the fact that for the first time new storage stations (batteries) were put into operation, contributing to the normalisation of cargoes. Their successful integration into the system is a prerequisite for the increased role that storage is expected to play in the coming years, as the penetration of RES increases.
The major change in the distribution network
If something stood out this year, this was the spectacular improvement in the management of the distribution network by the TEN.
Unlike Easter 2025, when management was largely based on manual interventions and mass communication with producers, in 2026 a clear transition to a centrally controlled and digitised operating model is recorded.
The data shall indicate:
• In 2025 there was a remote control facility for 1,638 RES stations (2,286 MW)
• In 2026 this number increased to 6,200 stations (5.4 GW)
• Total installed RES power reached 9 GW, increased by 550 MW
With the creation of two new Control Centres, HEDNO acquired the possibility of direct remote control and targeted cutbacks in real time, significantly reducing operational risk.
This progress is also reflected in reducing the need for network interventions. While in 2025 the so-called "Group B" was activated in 14 cases, in 2026 the corresponding days were limited to only 7, despite significantly increased production from RES.
This development is linked not only to technological upgrades, but also to the formation of a more competitive and mature market operating framework, which limits the need for administrative interventions.
The market message
This year's Easter clearly highlighted the new challenges posed by the energy transition: high RES penetration, production variability and often negative prices. At the same time, however, it showed that the Greek electricity system gradually acquires the tools to manage them.
The combination of enhanced infrastructure, better coordination and active market participation creates the conditions for a more durable and flexible system, in the interests of both energy security and consumers.
The next bet remains the further development of storage and flexible loads, so that oversupply phenomena can be converted from problem to opportunity for lower energy costs.
