Evolution of the Efficiency of a Photovoltaic/Supercapcitor System with Aging

The evolution of the optimization of photovoltaic/supercapacitor system according to its age is inquired. The system is modeled by an accurate equivalent circuit. The durations and energies of charge/discharge cycles are calculated for a 10 year use. The temporal and energy efficiencies are then deduced according to time, and optimal values are hence extracted. Results show that the optimal efficiencies can be kept constant over time at a value around 90% for the energy. However, the amount of energy stored and released by the supercapacitors is reduced over the years and the response time becomes shorter. So, the behavior of the system is modified with aging regarding its initial nominal functioning. This has to be considered to know the real profitability of the system.