Innovative renewable routes are potentially able to sustain the transition to a decarbonized energy economy. Green synthetic fuels, including hydrogen and natural gas, are considered viable alternatives to fossil fuels. Indeed, they play a fundamental role in those sectors that are difficult to electrify (e.g., road mobility or high-heat industrial processes), are capable of mitigating problems related to flexibility and instantaneous balance of the electric grid, are suitable for large-size and long-term storage and can be transported through the gas network. This article is an overview of the overall supply chain, including production, transport, storage and end uses. Available fuel conversion technologies use renewable energy for the catalytic conversion of non-fossil feedstocks into hydrogen and syngas. We will show how relevant technologies involve thermochemical, electrochemical and photochemical processes. The syngas quality can be improved by catalytic CO and CO2 methanation reactions for the generation of synthetic natural gas. Finally, the produced gaseous fuels could follow several pathways for transport and lead to different final uses. Therefore, storage alternatives and gas interchangeability requirements for the safe injection of green fuels in the natural gas network and fuel cells are outlined. Nevertheless, the effects of gas quality on combustion emissions and safety are considered.

Nowadays, energy policymakers are asked to develop strategies to ensure an affordable clean energy supply as well as minimizing investment risks. In addition, the rise of several community engagement schemes and the uptake of user-scale technologies introduce uncertainties that may result in a disruptive factor for energy systems evolution. This paper introduces a novel scenario analysis approach for local energy planning that supports policymakers and investors in prioritizing new renewable power plant investments, addressing the risks deriving from citizens’ choices. Specifically, a combined analysis is performed on the adoption trends of distributed photovoltaic systems and electric vehicles that are expected to heavily influence the evolution of energy systems. For this reason, an energy model is developed for Pantelleria island, and its transition from an oil-based energy supply to a renewable one up to 2050 is investigated. It is demonstrated how optimal-cost renewable-based scenarios can assure a 45% to 52% CO₂ emissions reduction and a 6% to 15% overall cost reduction with respect to the diesel-based business-as-usual scenario. The analyzed scenarios disclose the recommended investments in each renewable technology, considering their learning curves and the unpredictability of user-scale technology adoption. Consequently, priorities in the installation of renewable power plants are stressed, starting with the most resilient to future uncertainties, as well as promoting specific incentive measures for citizens’ commitment at a local scale.