# Increasing Photovoltaic Systems Efficiency Through the Implementation of Statistical Methods
## 2 Literature Review
### Prediction of PV System Performance Using PVGIS Platform  
A geographic information system (GIS) is a computer system used to create, store, analyse, and process global information. GIS technology can be applied in various scientific \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Panel Type** & **Surface** & **Peak Power** & **Efficiency** & **Technology** & **Price** & **Price Ratio** & **Power Ratio** \\  & **[m\({}^{2}\)]** & **[Wp]** & **[\%]** & **[USD]** & **[USD/Wp]** & **[W/m\({}^{2}\)]** \\ \hline Yingil Solar & 1.9 & 330 & 17 & Si-polycrystalline & 109 & 0.33 & 174 \\ Solaro LB5-72H1-575M & 2.5 & 575 & 22.3 & Si-mono N Multi Busbar & 140 & 0.24 & 230 \\ ENF-Germany & 2.6 & 580 & 22 & HIT Half-Cell Bitalcal & NA & 0.35 & 223 \\ Risent EARM132 8 660 & 3.1 & 660 & 21.3 & Mono PERC BIFACIAL & 297 & 0.45 & 213 \\ Jinko Solar RM408-5H14E-W & 2.27 & 460 & 20.3 & Si-mono Bite. Half-Cut & 118 & 0.26 & 203 \\ Canadian Solar CRS3-573 MS & 1.8 & 375 & 20.8 & Mono PERC & 95 & 0.25 & 208 \\ JA Solar JA72530 & 2.5 & 550 & 22 & PERC & 200 & 0.4 & 220 \\ Macsun Solar Ms-Hcpv120w & 0.48 & 133 & 28 & GaAs Si Fresnel lens & 286 & 2.15 & 277 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Commercial analysis of the PV market in Romania for 2024.  
fields, including resource management, environmental impact studies, mapping, and route planning. For photovoltaic system applications, the most used are the web applications from the National Renewable Energy Laboratory (NREL) and PVGIS. NREL is led by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy and the Alliance for Sustainable Energy, LLC, a partnership between Battelle and MRIGlobal. NREL's geospatial data science research utilises geographic information systems to produce maps, analyses, models, applications, and visualisations that inform energy planning and production, including the PVWatts Calculator. The analogue of this application for Europe is the PVGIS Platform. PVGIS is a web application that provides users with data on solar radiation and energy production generated by photovoltaic systems in most parts of the world. It is entirely free to use, with no restrictions on how the results can be used, and no registration is required. The application utilises terrestrial and satellite databases that have been statistically processed over extended periods [33]. The necessary input data consider the following:  
* The location on the displayed map or the analytical entry of the geographical position (latitude and longitude);
* Choosing the database for solar irradiation;
* Photovoltaic cells/panels technology (Si-mono/polycrystalline);
* Installed power of the photovoltaic power plant [kWp];
* System power losses (typical 14%);
* Orientation of the panels according to azimuth (\(-90^{\circ}\) East, \(0^{\circ}\) South, and \(90^{\circ}\) West, respectively);
* Orientation of the panels according to the angle of inclination to the horizontal--in the case of the mount without tracking;
* Characteristic of the tracking system (one or two axes);
* Economic data:
* Cost of investment (in the currency of the respective country);
* Interest rate [%/an];
* Estimated service life [years].