Energy harvesting on its way to a reliable and green micro energy source

Steadily reducing power consumption of microelectronic components in conjunction with developments in the area of energy harvesting devices, power management circuits and energy storage have led to technically feasible solutions for autonomous power supplies. First generations of fully autonomous electronic systems have been applied in industrial process chains and building automation where significant potentials to save installation and maintenance costs are foreseen. With energy harvesting systems having a significant potential to power future applications analysis of both, technical and environmental performance has become an inevitable aspect of system design. This paper analyses the interdependencies between ambient conditions, system-behavior and environmental impacts associated with two energy harvesting systems. Currently developed thermoelectric and piezoelectric energy conversion chains are compared to the conventional use of Li-based batteries. For that purpose, screening methods focusing on the material contents toxicity and scarcity are applied considering different realistic ambient conditions. Results of this study show that both, definition of sufficient levels of ambient energy as well as minimum operating times are key requirements to achieve environmental benefits when implementing these technologies.