Solar photovoltaic (PV) systems have experienced a tremendous increase in installed capacity in the past decade. Although solar PV power is environmentally friendly and can be used to extend the life of fossil fuel reserves, it is of an intermittent nature. Through nine chapters, this book provides an understanding of solar PV systems' power output intermittency and its impacts on power systems. The first part of the book highlights the source of the variability of both solar irradiation and PV systems' output, while the second highlights the impact of factors such as temperature and dust on PV systems' output variability through case studies. The third part highlights the impacts of PV systems' output variability of the design and operation of power systems. This book will appeal to students, researchers, operators, engineers, designers, and policymakers working on solar PV or electric power systems design, planning, or operation.