Techno-economic Analysis of Hybrid Renewable Energy Storage Optimal Sizing in Urban Energy System

Advances in renewable energy systems have inevitably created opportunities like realizing self-sufficient and carbon emission-free energy systems and challenges such as optimal scheduling and sizing of single or multiple energy storages in energy systems. This study discusses the technical and economic objective functions for optimum sizing of renewable energy storage in the urban energy system i.e. grid and solar photovoltaic as the main power generation sources. It is perceived that leveraging energy storage according to the capability of each storage technology is the intelligent approach, as each storage technology comes up with some merits and demerits such as battery storage has a rapid response i.e. less than one second and higher round trip efficiency i.e. greater than 90% but it has a self-discharge rate of around 1% and capacity loss of 20%. As far as hydrogen storage is concerned it has a higher energy density but cycle efficiency of hydrogen storage is merely 50%. So, using these renewable storage technologies individually does not result in an efficient, economical, and reliable system. Thus, this paper analyzes the different combinations of these storage technologies into hybrid optimization by implementing, volatile grid electricity rates, limiting battery operation, precise battery and hydrogen usage, and limiting grid operation to achieve lowest energy cost, capacity shortage, and net present cost objective functions.