Exploring the gaps in renewable energy integration to grid

The continued integration of diverse renewable energy sources into the power grid has led to a significant decrease in power system inertia, thus resulting in several challenges in the electric power system such as frequency instability and sharp rise in rate of change of frequency (rocof). In order to combat these challenges, several technologies such as the use of energy storage systems, hybrid energy storages system and hybrid systems have been used to provide fast frequency response and regulation. This paper gives a comprehensive review of these technologies thus highlighting their applications, merits and demerits for frequency regulation in renewable energy sourced grid. Furthermore, the research reveals that hybridized system provides better characteristics than singly sourced renewable energy system, therefore the best suited hybrid system can be formed based on the desired power grid characteristics and specific power requirement. Finally, it was revealed that FESS, SMES and SCES have similar characteristics, nonetheless, their characteristics is complimentary to that of BESS, CAES and PHES technology, and so a hybrid combination comprising of BESS and SCES could be best suited for fast frequency response in renewable energy sourced grid. (C) 2020 The Authors. Published by Elsevier Ltd.