ABSTRACT
Today, the use of renewable energy is considered a desirable alternative to fossil fuels. The increase in environmental pollution and the reduction of fossil fuel resources are two powerful factors that have led to an increase in the use of renewable energy in electricity generation. In this study, a plan for using solar energy to supply electric energy to an electric vehicle charging station in Rasht city is presented, and the amount of carbon dioxide pollutant reduction is examined. Thus, for the study charging station, the number of photovoltaic panels required is estimated according to the peak sunshine hours for the study area. Then, over a 25-year period, the percentage of pollutant reduction for electricity generation using solar energy compared to a combined cycle power plant is evaluated. According to studies conducted in the design of a solar charging station for study vehicles, in the most case, 18 photovoltaic panels with a power of 745 watts are required. The amount of carbon dioxide pollutant when using a combined cycle power plant to supply electricity to the charging station in question is estimated to be about 1.1 tons per year at maximum, while this parameter has been reduced to 0.13 tons when using solar energy.

Introduction
The increase in environmental pollution on the one hand and the decrease in fossil fuel resources on the other hand have led many researchers to research renewable energies such as wind, solar, geothermal, etc. Among them, solar energy has received more attention due to its availability. According to studies, Iran has rich fossil fuel resources, but due to the limitations on the use of renewable energies and its suitable geographical location, favourable radiation intensity, and high potential for absorbing solar energy, the most appropriate way to use photovoltaic systems is to supply electrical energy. Iran is one of the largest producers of greenhouse gases, so the need to use renewable energies to control pollution has increased. On the other hand, due to Iran's location on a belt with high potential for receiving solar energy, it is considered one of the countries suitable for the utilization of this clean energy, which, with careful management in this regard, can be used for various applications. In this study, the amount of energy required by the electric vehicle charging station was initially evaluated. This was done by examining some electric and hybrid vehicles and determining the capacity required for charging their batteries. In the next step, considering the existing photovoltaic panels, the number of panels required was evaluated and a plan for solar energy efficiency in the charging station was presented. Finally, considering the power required by the charging station, the amount of carbon dioxide pollutant reduction was evaluated.

Materials and methods
Rasht is the capital of Guilan province and the most populous city in the province. Due to the existence of the Bandar Anzali Free Zone in this province, many electric and hybrid vehicles are circulating in this province. On the other hand, the companies of Modiran Khodro and Kerman Motor have also launched their electric and hybrid vehicles. Therefore, the need for charging stations in this city has increased. With increasing population growth, urbanization, and rising energy consumption worldwide, the need for sustainable, clean, and renewable energy sources is felt more than ever. In the meantime, solar energy, as one of the most abundant and accessible natural resources, has found a special place among renewable energy options. Sunlight, which is available daily and free of charge, has the ability to be converted into electrical and thermal energy and can meet various needs, including providing electricity to households, industries, agriculture, and transportation. A photovoltaic system consists of various components such as photovoltaic panels, a charge controller, inverter and etc.

Results and discussion
In this study, photovoltaic panels are used to utilize solar energy. It is assumed that the solar charging system operates only when solar energy is available. Therefore, the value of the parameter t is changed between 4 and 6 hours according to the peak of the sunny hours, and the number of panels required is estimated at each stage. The number of days the system is active is considered to be 365 days. To obtain the maximum output power, heat losses, cables, batteries, and mismatches must first be evaluated. The highest battery capacity among the study vehicles is for the Peugeot 208. Therefore, if the designed charging station is capable of charging this car, it can also charge other cars. In this section, the amount of carbon dioxide reduction for the 51 kWh charging station and for the peak sunny hours is evaluated differently, considering the 25-year life of the photovoltaic panels. The amount of carbon dioxide produced when generating electricity by a combined cycle power plant is much higher than that produced by solar energy. Assuming a 6-hour operation of the solar charging station, it results in a reduction of about 22.4 tons of carbon dioxide produced.

Conclusion
In recent decades, challenges such as the reduction of fossil fuel resources, the increase in greenhouse gases, and environmental pollution have increased the need for research on renewable energies. Among them, solar energy, as the most available renewable energy, is very important. In this study, solar energy has been used to supply the electricity required by the electric and hybrid vehicle charging station in Rasht city, Guilan province. In this way, the battery capacity of some electric and hybrid vehicles has been examined first. In the next stage, the climatic conditions and solar radiation at the study station have been evaluated, and a plan has been presented to utilize this clean energy for use in the electric and hybrid vehicle charging station. Finally, the amount of carbon dioxide reduction in the case of using solar energy in the electricity generation of the charging station has been evaluated in comparison with the use of a combined cycle power plant. According to studies, the reduction in carbon dioxide emissions over the 25-year life of photovoltaic panels has been estimated at 14.9 tons when the charging station is operating for 4 hours and 22.4 tons when it is operating for 6 hours.