Thermoelectric generators are devices which convert temperature differences into electrical energy. The principle phenomenon that underpins thermoelectric energy generation is known as the Seebeck effect: the conversion of a temperature differential into electricity at the junction of two materials.Although thermoelectric phenomena have been used for heating and cooling applications quite extensively, electricity generation has only seen very limited market in niche applications and it is only in recent years that interest has increased regarding new applications of energy generation through thermoelectric harvesting.The new applications are varied and the vertical markets benefiting from new devices range from condition monitoring in industrial environments, smart metering in energy market segments, to thermoelectric applications in vehicles, either terrestrial or other.This report gives an overview of devices, materials and manufacturing processes, with a specific focus on emerging technologies that allow for new functionality, form factor and application in various demanding environments. Whether it is operation in high temperatures or corrosive environments, applications with increased safety demands or components that need to be thin, flexible, or even stretchable, there is a lot of research and development work worldwide which is highlighted.