This is a second edition of Masters' comprehensive textbook Renewable and Efficient Electric Power Systems for the new trend of distributed power generation systems and renewable energy sources in electric power systems. It covers the complete range of topics from fundamental concepts to major technologies as well as advanced topics for power consumers. As a textbook it serves undergraduate students from a variety of disciplines such as mechanical, chemical, civil and environmental engineering, and electrical engineering, with signifcant updates in geothermal power, wave and tidal power, and ocean thermal energy.