Modelling, simulation and testing of an autonomous embedded system supplied by a photovoltaic panel

The concept of energy harvesting, to produce electrical energy from other existing forms of energy from the environment, has become very popular for a range of low power applications, like wireless sensor networks, data-loggers or identification devices. Solar energy is the best type of energy harvesting in terms of produced power, but has a major drawback - no available energy during the night. A solution to compensate this problem is to store electrical energy in the daytime and to offer it in the night; there are many implementations, involving use of different type of accumulators (lead-acid, NiMH, LiIon) or supercapacitors. Presented paper focuses on modelling and simulation of an autonomous embedded system that uses supercapacitor for energy storage and photovoltaic panel for power generation. Design, implementation and testing of the embedded system are also presented.