Nikos Mantzaris and Ioanna Souka participated as speakers, on 3 June 2025, at the event “Energy Transition & Electricity,” organized by Clima21 and the Aegean Energy & Environmental Bureau (EPEGA) at ESIEA. The event focused on critical issues for achieving climate goals and developing clean technologies.
Capacity Mechanisms
Nikos Mantzaris took part in a panel discussion titled “Challenges for the Post-Lignite Era: Transmission and Distribution Network Issues for Maximizing Renewable Energy Penetration; Grid Capacity, Demand Management, Renewable Energy Curtailment, and Storage Needs; Capacity Mechanisms.” The panel included Giorgos Amanatidis (Regional Governor of Western Macedonia), Pantelis Biskas (Professor at the Aristotle University of Thessaloniki), Panagiotis Ladakakos (Chairman of the Hellenic Wind Energy Association – ELETAEN), Kostas Tsirekis (Director of Strategy & System Development Planning at IPTO), and Stavros Papathanasiou (Professor at the National Technical University of Athens).
Nikos Mantzaris emphasised that “Capacity Mechanisms (CMs) impose financial burdens on electricity consumers. If not properly designed and if they excessively support fossil gas units, they will disproportionately increase electricity prices and delay the urgent decarbonisation of the power sector.”
He outlined the essential steps required by European legislation for a member state to establish a CM, highlighting the need for a Capacity Adequacy Study to first demonstrate the necessity of such a mechanism and then quantitatively define the required capacity to ensure energy adequacy at the lowest possible cost. Since such a tool is currently absent from Greece’s energy planning, Nikos Mantzaris warned of the risk of excessive financial support for unnecessary gas units.
He presented findings from The Green Tank’s analysis based on entso-e data, indicating that the maximum thermal capacity utilised by the country at any given time is currently well below the total installed gas capacity (6 GW). Nevertheless, the construction of new gas units (up to an additional 5.5 GW) is being promoted, which, if implemented and financially supported through a CM, would lead to exorbitant electricity costs, adversely affecting households, businesses, and the competitiveness of the national economy.
Finally, he discussed European trends regarding CMs, noting the increasing share of storage and other clean flexibility technologies among the units financially supported by CMs, as well as the lower cost of strategic reserve CMs—where participating capacity units are kept out of the electricity market—compared to market-based CMs, where units are paid both for their capacity availability and the energy they produce. He concluded by proposing that “Greece should invest in clean flexibility technologies, such as storage and demand management, to support further renewable energy penetration while reducing dependence on expensive and polluting fossil fuels.”
Energy Communities and Self-Production
Ioanna Souka participated in a discussion titled “Smart Energy Communities, Digitalisation, and the Role of Data: The Role of Local and Regional Authorities and Challenges for Self-Production; Programmes like ELECTRA, APOLLON, etc.; Crowdfunding Mechanisms and Mediation by Private Sector Companies; International Practices.” The panel included Miltos Aslanoglou (General Director of the Hellenic Association of Energy Suppliers), Christina Giavasoglou (Chemical Engineer at NTUA), Christos Vrettos (Policy Officer at Electra Energy – European Federation of Energy Cooperatives REScoop.eu), and Petros Markopoulos (Director of European Projects at DAFNI).
“Citizens have actively participated in the energy transition, either through individual self-production projects or collective energy community schemes. However, challenges such as insufficient grid capacity, inadequate financial support, and frequent legislative changes have contributed to a decline in interest for such projects,” Ioanna Souka stated.
She focused on the developments of energy communities and self-production in Greece, presenting key findings from The Green Tank’s recent review, which shows that to date, 1,703 energy communities have been established, with a total requested capacity of 4,920 MW. However, only 28.4% of this capacity has been electrified, and since 2024, there has been a stagnation in new applications, primarily due to changes in the regulatory framework.
Regarding self-production, she noted that the electrified capacity has nearly reached the milestone of 1 GW, but there has also been a significant slowdown in new applications. The main reason was the transition from the net metering scheme to net billing. Beyond the significant delays in issuing decisions for the operation of net billing, the new scheme increases the project’s payback cost. This has heightened uncertainty and reluctance among citizens and entities to invest in new projects. Therefore, providing financial incentives is deemed necessary to support the implementation of self-production projects.
Additionally, she highlighted the numerous projects pending approval, which, along with the electrified projects, approach the milestone of 2 GW of grid capacity allocated for self-production projects. Therefore, she stated that “increasing the available grid capacity for self-production projects to 3 GW by 2030 and enabling energy sharing instead of selling to the market will accelerate the sector’s development.” Finally, she proposed the participation of citizens and energy communities in large renewable energy projects through shareholding, so that “the energy transition is not only green but also socially just and participatory.”
This event was the second of three held on May 30 and June 3–4, 2025, highlighting challenges and proposals for a more sustainable energy policy, with an emphasis on transparency, innovation, and consumer protection.