Using formulas simple enough to be applied using a pocket calculator, this book presents analytical methods for transient analysis. It examines the theory of numerical simulation methods, such as the EMTP (circuits theory-based approach) and numerical electromagnetic analysis. The book highlights transients in clean or sustainable energy systems, such as smart grids and wind farms, since they require a differentapproach than overhead lines and cables. The simulation examples provided include: arcing horn flashover, a transient in a grounding electrode, and an induced voltage from a lightning channel.Abstract: Using formulas simple enough to be applied using a pocket calculator, this book presents analytical methods for transient analysis. It examines the theory of numerical simulation methods, such as the EMTP (circuits theory-based approach) and numerical electromagnetic analysis. The book highlights transients in clean or sustainable energy systems, such as smart grids and wind farms, since they require a different approach than overhead lines and cables. The simulation examples provided include: arcing horn flashover, a transient in a grounding electrode, and an induced voltage from a lightning channel