The Iveron Monastery is located by the sea, in the northeast side of the third peninsula of Halkidiki Greece. It was built at the end of the 10th century. The largest part of the aisles isles has been rebuilt during the 19th century. Iveron hosts at any time, about 100 people living within the main building structure and nearby shelters. Additionally, it features wood, stone and marble processing facilities, various farming activities, a restaurant and a museum. Therefore, Iveron may be considered as one typical example of a small autonomous energy community.
There is no connection to a central electric transmission/distribution grid and thus lightning and electrical appliances are electrified by stand alone diesel generators. More precisely, the average day electrical consumption of the Monastery is roughly 1000 kWh, serviced by one diesel generator of 250kW. Heat is provided by biomass burners via the central heating system in the main building structure and with biomass stoves, fan coils and electric heaters in other shelters. The night electrical consumption is approximately 500 kWh and it is served by a second smaller diesel generator of 100kW. A ground mounted PV system of 83kWp was integrated into the existing diesel system, forming an Autonomous Hybrid PV E.CO. Due to the historic and archaeological value of Iveron Monastery the installation of PV modules was not allowed either on the roof or in places visible from the Monastery. Therefore, the PV system was installed in a clearing near the monastery and the produced energy is transferred via a Medium Voltage (MV) line.
A PV system controller ensures that the maximum PV yield is generated during any given situation. Furthermore, it monitors the diesel generator to ensure that it is always operating at an optimum level to prolong its service life and ensures an extremely quick and responsive adjustment over the PV output. As a result, load fluctuations are compensated immediately, and the oil consumption of the diesel generator has been considerably reduced. In cases where there may be excess of produced PV energy, the controller adjusts the MPPT operation of each inverter reducing the produced PV energy. Energy storage systems and battery inverters are not installed, in order to minimize the initial cost of the PV system.
Iveron PV E.CO constitutes a real-world example of the kind of electrical services that is currently provided in non-interconnected areas and, more generally, in weak electrical grids. Indeed, this case study is a representative example for the integration of PV E.COs in grid- constrained areas. In this context, it is noted that the majority of islands in Greece remain isolated from the main national power system, relying on diesel generators or oil-fired plants. Therefore, this proposed PV case study will lead to a useful business model in order to increase the penetration of PV E.COs in grid- constrained areas