A paper* to be presented at the 35th International Telecommunications Energy Conference
Summary / Abstract
This paper presents the design, deployment and operation of an isolated smart grid in Xanthi, Greece. The overall topology and the architecture of the grid is analyzed, including the power production, transmission, consumption and the communication infrastructure. The grid consists of three smaller microgrids that are connected together through a common DC bus. Each microgrid consists of equipment exploiting various renewable energy sources, a local load, a battery and a diesel generator. In the third microgrid, hydrogen is also utilised by a long term energy storage facility. A case study shows that when the three microgrids are connected allowing energy exchange among them, the overall efficiency is greatly increased as the usage of the diesel generators is reduced and the available energy is fully exploited.
Traditional power grids consist of four distinctive components: generation-transmission-distribution-consumption. The energy flow is unidirectional from the few central power generation stations to the consumer. This topology suffers from three main problems; the efficiency significantly drops due to losses during the transmission stage, the grid is not designed for equipment facilitating distributed generation such as Fuel Cells (FCs) and Photovoltaic panels (PVs), while the effects of locally observed malfunctions or other similar problems are easily propagated throughout the entire grid . For this reason, an information grid is placed on top of the power grid and with the use of modern power electronics; energy and information can easily be transmitted in multiple directions within the grid . Thus, it is possible to use distributed sources for power generation and more importantly the grid can be split into smaller parts (islands) and hence reduce the losses due to the transmission and avoid the spreading of faults . These so called smart grids have become particularly attractive especially in isolated areas where the connection to the main grid may not be feasible or it may be financially prohibiting. In this paper three standalone or isolated microgrids are connected together forming a smart grid which is supported by Information Technology (IT) specifically developed infrastructure. The three microgrids have been constructed and commissioned in the area of Xanthi, Greece and the main focus of this work is the investigation of issues associated with their interconnection, the IT support and the energy management strategy employed in order to facilitate energy exchange among the three systems. A case study clearly shows that when the three microgrids are connected together, the performance of the system is greatly improved. In section 2 the main system is described including the IT infrastructure, the power management strategy and a case study illustrating different aspects of interest regarding the operation of the smart grid. Finally, in section 3 the results of the case study are presented and analysed.
* A Paper by Damian Giaouris (Centre for Research and Technology Hellas & Chemical Process Engineering Research Institute, Greece); Chrysovalantou Ziogou (Centre for Research and Technology Hellas, Greece); Athanasios Papadopoulos (Centre for Research and Technology Hellas, Greece); Dimitris Ipsakis (Centre for Research and Technology Hellas, Greece); Panos Seferlis (Aristotle University of Thessaloniki, Greece); Simira Papadopoulou (Alexander Technological Educational Institute of Thessaloniki, Greece); Costas Elmasides (Systems Sunlight SA, Greece); George Sergiadis (Aristotle University of Thessaloniki, Greece); Spyros Voutetakis (Centre for Research and Technology Hellas, Greece).Batteries for Renewable Energy Sources, Batteries for RES, Battery Technologies, Diesel Generator, Intelec, Microgrid, Renewable Energy Sources, RES, Smart Grid