The Greek electricity distribution system operator, DEDDIE, has conducted an extensive assessment revealing that the national distribution network can potentially integrate a significant amount of battery energy storage, estimated between 1.8 and 2.9 GW. This evaluation is crucial in understanding how much standalone storage can be added without jeopardizing the stability of the network.
This analysis specifically targeted the mainland network, assessing the operational capabilities of 230 substations and 453 power transformers. Findings indicate that areas with high solar energy penetration are optimal for battery connections due to their predictable generation patterns, which facilitate effective charging and discharging processes that help alleviate network congestion, unlike more erratic energy sources such as wind or hydropower.
DEDDIE has pinpointed 70 substations as priority sites for merchant battery projects based on their capacity to manage high solar output. These locations were selected due to their ability to enhance electricity flow and mitigate local overloads. The study highlighted notable regional disparities; while Attica and Epirus present limited opportunities owing to fewer suitable substations and lower solar density, regions like central Greece and central Macedonia could accommodate nearly double the capacity, benefiting from robust photovoltaic deployment and available network infrastructure.
However, the report cautioned that the advantages of larger battery installations do not scale linearly. Beyond a specific threshold, additional storage may yield diminishing returns concerning congestion relief. The analysis suggests that an optimal battery capacity should fall between 1.15 and 1.7 GW to maximize system efficiency gains.
The implications of these findings are significant for Greece’s energy landscape as the role of energy storage becomes increasingly vital in an electricity system where solar power is rapidly expanding. By the end of 2025, projections indicate that the distribution network will support approximately 9 GW of renewable capacity, including around 7.2 GW from solar sources. Concurrently, the transmission network is expected to reach a total of 8.1 GW, with solar contributing about 3.7 GW. These developments underscore why battery storage is evolving into a critical component of energy infrastructure rather than merely serving as an ancillary technology.
