This study focuses on an overall energy consumption prediction for the area of Stuttgart city in Germany and a specific analysis of a solar-fed power-to-gas plant in an industrial area close to Stuttgart. In order to achieve decarbonisation targets, a sustainable concept of hydrogen production and mobility based on renewable energy and a zero-emissions scenario was defined. First, an energy system analysis was conducted to assess the viability of hydrogen as fuel in the system context. Scenario results indicate the increased penetration rate of electric mobility with systematic repercussions on other traffic, power generation and consumption as well as the achievement of the local targets for the reduction of greenhouse gas emissions. As a result, this allows us to make an assessment regarding the relative advantages of hydrogen over alternative propulsion technologies. In a second step, the minimum purchase costs of hydrogen are determined, based on a total-cost-of-ownership calculation for an individual energy plant application. In a last chapter of this work, a study was conducted on a zero-emission bus fleet using the total costs of mobility method. The results of this study serve a pioneering role model in urban areas and shall be transferable to projects throughout Europe. Copyright © VBRI Press.