## 3 Calculation Methodology of the PVCS Carbon Impact
### Presentation of the Study Perimeter
#### 3.2.1 Carbon Impact of the PV System  
To calculate the carbon impacts of the PV system components, a methodology using the LCA method is detailed. As depicted in Figure 1, the total carbon impact of the PV system includes the carbon impact of the manufacturing of the PV system components, the installation and uninstallation of the PV system, and the use and maintenance. In this study, the environmental assessment is applied according to the PV system category. The product category is the group of products with equivalent functionality. These are PV systems connected to a public low voltage, medium voltage, or high voltage power grid. These categories differ according to the maximum power of the PV system, the voltage range, and the installation of the system. They vary between product category 1 and product category 3b. The type of PV panels selected for the global overview of this study is the monocrystalline silicon panel, the most prevalent technology in France. The carbon emissions coefficient of the PV system \(CO_{2,PV,syst}\) (kgCO\({}_{2,\text{eq}}\)/kWh) is calculated using the following general equation:  
\[CO_{2,PV,syst}=\frac{Imp_{PV,syst}}{E_{PV,syst}} \tag{25}\]  
where \(E_{PV,syst}\) is the energy produced by PV installation (kWh) during the analysis period. The carbon impact of the PV system \(Imp_{PV,syst}\) is the sum of the carbon impacts of the PV system components \(Imp_{PV,infra}\), construction site \(Imp_{site}\), and maintenance \(Imp_{maint}\) in kgCO\({}_{2,\text{eq}}\), as shown in Equation (26):  
\[Imp_{PV}=Imp_{PV,infra}+Imp_{site}+Imp_{unit} \tag{26}\]  
Each of these three carbon impacts is calculated in the same way. The equations evaluating these carbon impacts are shown below. The \(Imp_{PV,infra}\) is calculated as follows:  
\[ \begin{array}{ll}Imp_{PV,infra}&=Imp_{PV~{}panels}+Imp_{inverter}+Imp_{ support}+Imp_{elec~{}cx}\\ &=CO_{2,PV~{}panels}\cdot P_{p}+(CO_{2,inverter,a}\cdot P_{inverter}+CO_{2,inverter,b})+CO_{2,support}\cdot A_{PV}+CO_{2,dec~{}cx}\cdot P_{p}\end{array}  \tag{27}\]  
Figure 1: Perimeter of the study. where \(Imp_{PV~{}pands}\), \(Imp_{inverter}\), \(Imp_{support}\), and \(Imp_{elecnx}\) are the carbon impacts of the PV panels, the inverter, the support, and the electric connections, respectively (kgCO2,eq), \(CO_{2 PV~{}panels}\) is the carbon emission coefficient of PV panels (kgCO2,eq/kWp), \(CO_{2,inverter,a}\) is the carbon emission coefficients of inverter a (kgCO2,eq)/kVA), \(CO_{2,inverter,b}\) is the carbon emission coefficients of inverter b (kgCO2,eq), \(CO_{2,support}\) is the carbon emission coefficient of the support (kgCO2,eq/m2), \(CO_{2,elcenx}\) is the carbon emission coefficient of the electric connections (kgCO2,eq/kWp), \(P_{p}\) is the peak power of the PV installation in kWp, \(P_{inverter}\) is the power of inverters in kVA, and \(A_{PV}\) is the area of PV panels in m2. The assessment of the carbon impact of the site (installation and uninstallation) of the PV system is provided by Equation (28):  
\[Imp_{site}=Imp_{installation}+Imp_{uninstallation}=CO_{2,installation} \cdot P_{p}+CO_{2,uninstallation}\cdot P_{p} \tag{28}\]  
where \(Imp_{installation}\) and \(Imp_{uninstallation}\) are the carbon impacts of installation and uninstallation of the PV system in kgCO2,eq, respectively, \(CO_{2,installation}\) and \(CO_{2,uninstallation}\) are the carbon emission coefficients of installation and uninstallation of the PV system kgCO2,eq/kWp.