Power Line Communication (PLC) is a well-established technology that allows the transmission of data through electrical wires. A key advantage of PLC is its low cost of deployment when the electrical wiring infrastructure already exists, enabling it to compete or work in conjunction with wireless technologies. PLC has recently received growing attention and significant investments within the development of the Smart Grid (SG), that in turn requires sophisticated data exchange and communication. This book presents a comprehensive introduction to the principals involved in the use of narrowband and broadband PLC technologies in the SG, and to using these technologies particularly when intermittent renewable energies sources are employed. Chapters cover fundamental concepts of modern digital communications, the main coding techniques, specific characteristics of the PLC channels, the fundamentals of the SG, and the differences between the narrowband and broadband technologies for SG applications. The work covers the main standards and several related state-of-the-art works, as well as some key aspects of the use of renewable energy sources. Power Line Communication Systems for Smart Grids is essential reading for researchers, professionals and graduate students involved with the study and development of PLC systems, SG and related subjects.