Renewable energy integration, climate analysis, and efficiency optimization for greener transportation - case study in dobrogea

This paper presents a model for super-rapid charging stations powered by renewable energy sources and conducts an analysis of land suitability based on climatic parameters. Initially, data on temperature, solar radiation, and specific humidity were collected for three designated areas, followed by an examination of the variations in these values. Among the three cities, Cernavoda, Medgidia, and Ovidiu, two equal segments of approximately 30 kilometers each were established for the installation of photovoltaic panel systems on both sides of navigable canals. With each segment measuring 30 kilometers in length, a linear area of 60 kilometers was covered on both sides, resulting in approximately 767 photovoltaic panels per kilometer and an installed power of 514 kW per kilometer. The total installed power for the entire 60 kilometers is approximately 30.84 MW, necessitating the division of the network into 1028 kW segments, each with a 1250 kVA transformer with a voltage of 20/0.4 kV. Fifteen transformer substations must be installed on each side of the canal, totaling 30 substations for the entire stretch. The energy produced by this system is utilized for three electric vehicle charging stations, positioned every 15 kilometers on each side of the canal, resulting in six charging stations per segment. Excess energy is injected into the national electrical grid (SEN) via 20/110 kV substations. To achieve optimal efficiency, a 2x25 MVA substation is supplied by 15 transformer substations, one for each side of the canal. The electric vehicle charging stations are of the super-rapid type, with a capacity of 2x175 kW. Initially, these stations exclusively rely on photovoltaic panels for approximately six hours each day, but energy storage batteries can be installed to ensure continuous operation, even during the evening hours. Comparing the analysis of the two segments, it is observed that there are slight differences. In the second segment, closer to the Black Sea with higher specific humidity, there is a slightly higher annual energy production of 390 kWh compared to the first segment, despite similar solar radiation values. Notably, this analysis reveals that specific humidity as a climatic parameter does not significantly influence the efficiency of photovoltaic panels compared to the other two parameters. Through this project, the aim is to reduce pollutant emissions from vehicles on public roads while simultaneously decreasing carbon emissions by replacing conventional electricity generation plants.