In this study, the upstream process of the Green Hydrogen Supply Network (GHSC) is investigated, in which electricity from solar renewable energy is used in the electrolysis technique for the hydrogen production process. Initially, multiple criteria relevant to the solar plant location based on geographic, climate, and sun-earth interaction data are examined. In particular, seven input criteria are obtained from the area, the average air temperature, the average rainfall amount, the average precipitation days, the average relative humidity, the wind force, and the average yearly sunshine hours. Additionally, three output criteria are the population density, the direct normal irradiation, and the specific photovoltaic power output, respectively. Then, the case study of the state of Saxony-Anhalt in Germany inclusive of eleven districts and three independent cities is used as Decision-Making Units (DMUs), in which the Data Envelopment Analysis (DEA) technique is applied to explore each DMU’s relative efficiency. The obtained results show that about 57 percent of all the DMUs are found to be relatively efficient. The outcome of the study can be used to analyze strategic policy for GHSC involving the upstream and other operations in future studies.