Big Data Analytics in Smart Grids: A Comprehensive Twenty-Year Review of Methods, Applications, and Emerging Challenges

Over the past two decades, the transition from conventional power networks to smart grids has accelerated, driven by advances in digital communication and intelligent control technologies. Smart grids integrate sensing devices, automated metering, and data-driven management systems, producing large volumes of heterogeneous information across all operational layers. This review examines 220 publications from the last twenty years, highlighting major research trends, classifying works by publication type, and identifying the most influential journals and conferences. It also summarizes the contribution of each reviewed work and categorizes the analytical methods and smart-grid-related topics addressed. Finally, the paper outlines emerging challenges and future research directions that can further enhance the role of big data analytics in next-generation smart grids.