Renewable energies can enable embedded systems to be functional indefinitely. In particular, we go for green solutions usually for small autonomous sensors. Energy harvesting techniques have attracted much interest. “Green” is fast becoming a critical factor in embedded systems design. Selecting the right set of design choices can mean lower system power consumption – which may lead to smaller power supplies and smaller footprints, while maintaining high capability in the embedded application. An important aspect of green design is determined by the power budget allotted to the embedded system.