Evaluation of battery‐renewable hybrid stations in small‐isolated systems

Abstract

Hybrid power stations (HPSs) are virtual power plants comprising storage and renewable energy source facilities operated in a coordinated manner as dispatchable stations. The HPS concept has been introduced as a means to increase renewable penetration in saturated island systems. The main objective of this study is to shed light on the operation of battery-based HPSs in small-island systems and their investment feasibility. Anticipated benefits for the island system are quantified in terms of system production cost and renewable penetration, while the exploitation of available renewable energy by the HPS is analyzed and the internal operation of its components is evaluated. A mixed integer linear programming generation scheduling approach is used to conduct daily and annual simulations of the entire island generation system, while at the same time optimising the internal management of the HPS as well. Based on the operating results thus obtained, the economic feasibility of battery-based HPS investments using wind, photovoltaics or their combination as the renewable generation component is assessed, by utilising the levelised cost of energy as the primary evaluation index and accounting for the life expectancy of the HPS battery storage system.