Energy Self-Sufficiency and Resilience in the Municipality of Mantoudi-Limni-Agia Anna, Evia - Pumped Storage Hydroelectric Project in the location Paraskevorema

The starting point of this diploma thesis was the description of the concept of energy storage through pumped hydroelectric storage in the study area, as presented by the Deputy Mayor of Limni–Mantoudi–Agia Anna, Mr. Angelos Konstantinakis, to G-Fivos Sargentis in August 2026. The location and potential of the project under consideration were examined during a site visit conducted with Deputy Mayor Angelos Konstantinakis, Fivos Sargentis, and Professors Dimitris Koutsoyiannis and Nikos Mamassis on August 26, 2026, at the project site. Drone flights and detailed photographic documentation of the area provided the first data for an overall assessment of the site. The digital elevation model of the area (grid …) was provided by the Hellenic Cadastre, and we would like to thank Ms. Eleonora Tounousidou and Messrs. Spyros Kaggelaris and Christos Christodoulou for their support. Subsequently, the preparation of the present diploma thesis was proposed, which was structured as follows: The analysis begins with the presentation of the theoretical framework, which examines the global and national course of energy transition, the concept and levels of energy autonomy, the challenges arising from the stochastic nature of RES, and the critical importance of energy storage for ensuring system stability and reliability. Subsequently, the energy demand of the municipality is analyzed through the estimation of annual and seasonal consumption based on demographic and climatic parameters. Particular emphasis is placed on the examination of periodicity and autocorrelation patterns, as well as on demand forecasting through time series analysis. In parallel, a mapping of the area’s renewable energy potential — solar, wind, and hydrodynamic — is conducted, employing geospatial analysis to identify optimal installation sites. The core part of the study presents a case study of a hybrid energy system combining photovoltaic generation with pumped-storage hydropower. The required installed capacity, storage volume, land area, and elevation difference are calculated, aiming to design a natural storage system (“natural battery”) capable of balancing seasonal energy surpluses with peak demand periods. Furthermore, the technical design and sizing of the hydroelectric component are analyzed, including the selection of the natural cavity for the upper reservoir, the development of water balance models, the estimation of hydraulic losses, and the assessment of overall energy efficiency. Finally, a preliminary project budget is estimated using an empirical cost relationship per cubic meter of reservoir volume, derived from comparative data on existing Greek projects, thus providing an initial economic assessment. The findings highlight the technical feasibility and economic viability of the proposed model, establishing it as a reference framework for mountainous and insular regions, and contributing to the national strategy for sustainable development.