In recent years Thermoelectricity moves in microgenerators trend. Green energy, energy harvesting… The structure of this book contains detailed explanations addressed to a wide range of readers, which for the most part are not specialists in the field of Thermoelectricity, the basic ideas, important aspects of the practical application of thermoelectric microgenerators in the in energy harvesting. I will be glad, if this book will serve as a reference tool in developing appropriate solutions.