## 4 Results and Analyses of the Numerical Application of Global Cost and Carbon Impact of the PVCS
### Discussion  
The environmental benefits of the PVCS are assessed as the function of the energy mix of each country. The carbon impact of each country depends mainly on the thermal power plants, nuclear energy distribution, and the capacity of the renewable energies. For example, in France, with the high nuclear energy use, the charging infrastructure based only on the power grid has a lower carbon impact than the PVCS initially considered in this study. Each country displays its coefficient without giving details concerning the life cycle of each category of power plant. Thus, in this study, the developed methodology offers, with more details, to the decision maker a choice of infrastructure compatible with his spatial, ecological, and budgetary constraints.  
Similar works have been published by other researchers. In [18], an optimal configuration of PVCS for EVs has been analyzed technically and economically under different conditions of solar irradiation in Vietnam. However, the cost of building, allowing the creation and the coverage of parking places, is not included in the total cost, as well as the replacement cost of the charging terminals. In [33], a technical, environmental, and financial analysis of the feasibility of PVCS associated with a stationary battery storage for EVs (EV) located in China and the United States has been discussed, using the estimation of the energy balance, annual costs, and CO\({}_{2}\) emissions. However, the carbon impact from the manufacturing phase until the disposal of each element of the PVCS is not included in the CO\({}_{2}\) estimation, as well as there being a lack of actions to reduce this emission.  
In this context, this work details the entire methodology followed for the calculation of the global cost and the carbon impact of the PVCS, as well as the different actions to reduce it.  
Each scenario presented in the previous sections was able to reduce the carbon impact of PVCS compared to the initially considered charging station and PGCS.  
Thus, scenario 4 presents the lowest carbon impact, combining a carbon emission coefficient of 0.012 kgCO\({}_{2,\text{eq}}\)/kWh for PV panels and an infrastructure based on recycled materials. The variation rate of each scenario compared to the charging station only grid-connected is summarized in Figure 12.  
Thus, the analysis of action levers demonstrates that despite a very carbon-free French energy mix, it is possible to have a lower carbon impact of PVCS than PGCS. PV technologies are evolving very quickly. Thus, for recent PV panels with a greatly reduced emission coefficient, the carbon impact of the PVCS will be also greatly reduced.  
Figure 12: Variation rate for the different scenarios.  
Figure 13 depicts the carbon impact of the PVCS compared with the PGCS in different countries. The calculated carbon emission coefficient of the initially considered PVCS of 0.068 kgCO\({}_{2,\text{eq}}\)/kWh is lower than the PGCS based on the energy mix of different countries, with the exception of that of France, because the French energetic mix is very low.  
Scenario 4 makes the carbon emission coefficient of PVCS become 0.042 kgCO\({}_{2,\text{eq}}\)/kWh lower than the energy mix of different countries, even that of France.