Novel stand-alone, completely autonomous and renewable energy based charging station for charging plug-in hybrid electric vehicles (PHEVs)

Abstract

A novel stand-alone charging station (CS) powered by a combination of solar and wind energy in presence of a fuel cell (FC) system is designed and constructed for charging plug-in hybrid electric vehicles (PHEVs). The built CS is high-efficient due to putting to practical use a proposed novel variable step-size maximum power point tracking (MPPT) scheme applied to both photovoltaic (PV) and wind parts of the CS. The main defect of a stand-alone CS is its necessity to battery banks which not only are expensive but also provide short lifetime due to a considerable number of daily charge and discharge imposed to them in a CS. This problem has been solved in this study by utilizing a FC system as supporting power source playing two roles. First, whenever PV and wind power production is less than charge demand, the FC system produces extra electric energy required. Second, whenever PV and wind power production is more than charge demand, the electrolyzer of the FC system produces hydrogen by absorbing extra electric power available in the system. Thus, the FC system acts as a high-capacity storage device in continuously regulating charging power to instant charge demand. The CS has been built, and experimental measurements obtained from its realistic operation are presented that prove the novelty and contributions of the constructed CS compared to those available as:● For the first time, it uses a FC system with permanent lifetime and a total cost of about $21000 as the storage device of the CS instead of an associated 6.5 kWh Li-ion battery bank providing a short lifetime of about 500 days and a total cost of about $70000 per 30 years.● It is high-efficient due to using a proposed novel variable step-size MPPT scheme with the efficiency and tracking time of, respectively, 99.6% and 12 ms applied to both PV and wind parts of the CS that high efficiently converts solar and wind energy into electric power.● It is stand-alone, completely autonomous and 100% renewable energy based resulting in unavailability of any harmful environmental impact and the possibility of installing the CS in remote areas where there is no grid.● The total construction cost of the built CS is about $99500 with a payback period of only 16 months.