Abstract
Small-scale energy systems like mini-grids and energy islands can rely on different power production technologies aimed at granting a reliable and efficient energy supply. The implementation of proper management strategies is fundamental to control their operations, reduce the operational costs, control the connection to the grid, as well as increase the overall system efficiency. In this work, a Mixed Integer Linear Programming (MILP) algorithm has been developed to compute the optimal scheduling of generators and storage of energy systems and investigate how the latter affects the energy system efficiency. The algorithm has been tested on a case study constituted by four Internal Combustion Generators (ICGs) fed by different fuels and a Pumping Hydro Energy Storage (PHES) system, which equilibrates the energy production of the ICGs and limits their use. The algorithm calculates the optimal scheduling of the energy produced by the ICGs and the PHES, thus minimizing the total cost of the overall energy system considering two different cases. In the first case, the ICGs efficiency has been considered constant, in the second case, ICGs efficiency curves have been introduced to consider ICGs efficiency variabilities at partial load operations. Results show that the PHES system can play a key role to keep the ICGs operating near to their best efficiency point. © ECOS 2020.