Evaluation of centralized and distributed microgrid topologies and comparison to Open Energy Systems

Author

Annette Werth, Nobuyuki Kitamura, and Kenji Tanaka

Abstract

In this study we examine microgrid topologies that combine solar panels and batteries for a community of 20 residential houses: In the first case we consider a system with centralized PV panels and batteries that distributes the energy to the 20 homes. In the second case we consider 20 standalone home systems with roof-top PV panels and batteries. Using real electricity consumption and solar irradiation data we simulated the overall demand energy that could replaced by solar energy for both topologies. The centralized-resources approach achieves better performance but it requires extended planning and high initial investments, while the distributed approach can be gradually built bottom-up. We analyze the additional resource investment needed to reach the same electricity savings as for the centralized topology. Finally, we compare it to a hybrid approach named Open Energy Systems (OES), a 2-layered microgrid made of interconnected nanogrids and show that it improves the solar replacement ratio by autonomously exchanging energy with neighbors.