The book presents research on the applications of thermogravimetric analysis. It also presents a detailed analysis of thermoelectric devices for electricity production as well as the challenges and advantages of using approximate analytical model to simulate the performance of thermoelectric devices. An analysis of boiling and condensation from a thermodynamic point of view is also presented. The modelling of solar collectors is presented to study the performance of these collectors. A numerical model of ground heat pump is presented to evaluate thermal performance, and finally the modeling of solid oxide fuel cell for heat and power generation is also presented.