Energy storage for mitigating the variability of renewable electricity sources: An updated review

Wind and solar power generation is growing quickly around the world, mainly to mitigate some of the negative environmental impacts of the electricity sector. However, the variability of these renewable sources of electricity poses technical and economical challenges when integrated on a large scale. Energy storage is being widely regarded as one of the potential solutions to deal with the variations of variable renewable electricity sources (VRES). This paper presents an up-to-date review of the state of technology, installations and some challenges of electrical energy storage (EES) systems. It particularly focuses on the applicability, advantages and disadvantages of various EES technologies for large-scale VRES integration. This survey paper indicates that each challenge imposed by VRES requires a different set of EES characteristics to address the issue, and that there is no single EES technology that consistently outperforms the others in various applications. This paper also discusses external factors, such as mineral availability and geographic limitations, that may affect the success of the widespread implementation of EES technologies.