The Hellenic Electricity Distribution Network Operator (DEDDHE) has completed its largest-ever program to upgrade high-voltage to medium-voltage substations (150/20 kV), marking a major milestone in the modernization of Greece’s electricity distribution network. The initiative involved reinforcing 14 substations across the country, adding a total of 725 MVA of new capacity.
Boosting Renewable Integration and Grid Flexibility
This investment significantly expands available electrical capacity—creating essential headroom for connecting new renewable energy sources (RES), including solar and wind farms. It also lays critical groundwork for integrating grid-scale battery storage systems, further enhancing the flexibility, reliability, and resilience of Greece’s distribution network.
Upgrades were carried out either by installing new power transformers or replacing existing units with higher-capacity models. In parallel, the medium-voltage side of each substation was expanded to accommodate additional feeders—enabling more RES projects to connect efficiently to the grid.
Funded by EU Recovery and Resilience Facility
The project is co-financed by the EU’s Recovery and Resilience Facility (RRF), under Action 16899 of Axis 1.1: ‘Transition to an Environmentally Friendly Energy Model’. Notably, the program was selected for RRF funding in July 2022—and delivered within an exceptionally tight timeline: complex technical interventions were completed in under four years across diverse, geographically remote sites nationwide.
With the program now complete, Greece’s distribution network gains enhanced ability to absorb clean energy, strengthening supply security, operational agility, sustainable development, and progress toward national energy targets.
Substations Already Operational
- Ioannina I (50 MVA increase)
- Florina (50 MVA)
- Meliti Switching Station (50 MVA)
- Philippoi Switching Station (50 MVA)
- Eordaea (50 MVA)
- Megara (75 MVA)
- Domokos (50 MVA)
- Pilos (50 MVA)
- Oinofyta (50 MVA)
Substations Fully Constructed, Commissioning Expected This Year
- Arachthos Switching Station (50 MVA)
- Skidra (50 MVA)
- Spercheiada (50 MVA)
- Trikala Switching Station (50 MVA)
- Magiko (Xanthi) (50 MVA)
Tassos Manos, CEO of DEDDHE, stated: “With the largest substation reinforcement program ever undertaken by DEDDHE, we are creating the essential electrical infrastructure needed to support greater investment in renewables and energy storage—strengthening grid reliability, sustainability, and Greece’s energy transition.”