A critical review of energy storage technologies for microgrids

Energy storage plays an essential role in modern power systems. The increasing penetration of renewables in power systems raises several challenges about coping with power imbalances and ensuring standards are maintained. Backup supply and resilience are also current concerns. Energy storage systems also provide ancillary services to the grid, like frequency regulation, peak shaving, and energy arbitrage. There are several technologies for storing energy at different development stages, but there are both benefits and drawbacks in how each one is suited to determining particular situations. Thus, the most suitable solution depends on each case. This paper provides a critical review of the existing energy storage technologies, focusing mainly on mature technologies. Their feasibility for microgrids is investigated in terms of cost, technical benefits, cycle life, ease of deployment, energy and power density, cycle life, and operational constraints.