Recently, the PV system installation has reached a very high growth worldwide. Various research papers have explored PV systems' technical, economic, and environmental assessment in different countries. This paper presents an energetic, economic, and environmental analysis of 1 and 5 kW of PV systems of eight countries, including Japan, Australia, China, Germany, India, Italy, Spain, and Saudi Arabia, to help cover a wide range of influential geographic and economic factors that significantly influence the results. This paper aims to determine which country, out of a selection of eight countries, receives the most solar irradiation, generates more energy, shows the most PV system investment, and mitigates CO2 by using a PV system. Based on the analysis conducted, the best country that receives the most solar irradiation and generates more energy is KSA. On the other hand, India has the lowestLCOE among the given countries due to low operation and maintenance costs, while Japan and Germany have the highest LCOE. Spain has the lowest CO2 Mitigation among the given countries through implementing proposed PV systems. In contrast, KSA and Australia have the highest CO2 Mitigation. The study conducted in this work allows drawing essential conclusions that can assist researchers and governments in the studied countries to increase the investment of PV systems worldwide.