This course shows the fundamental know-how related to fuel cells and distributed generation systems. The attention is mainly focused on thermodynamic theory, component performance and economic aspects. Fuel cells are presented putting emphasis on different fuel cell typology, hybrid system layouts, technological and environmental aspects. Different small size systems (internal combustion engines, microturbines, stirling engines, fuel cells, renewable systems) are considered for distributed generation applications. For this part of the course, special attention is devoted to combined heat and power generation providing students with laboratory experiences.