A fully sustainable energy system for the Åland islands is possible by 2030 based on the assumptions in this study. Several scenarios were constructed for the future energy system based on various combinations of domestic production of wind and solar photovoltaic power, expanded domestic energy storage solutions, electrified transport, and strategic energy carrier trade. Hourly analysis of scenarios using the EnergyPLAN tool shows that annualised costs of operating a future sustainable energy system for the year 2030 range between 225 and 247 M€/a compared to 229 M€/a for the business as usual case. However, this result is highly dependent on how vehicle and battery costs are accounted. A scenario featuring a highly electrified transport sector, including a wide range of terrestrial and aquatic forms of mobility, was among the most cost competitive solutions due to high levels of flexibility and electric storage harnessed in the energy system. In this scenario cost reductions were achieved as high capacities of electric vehicle battery storage resulted in less need for seasonal storage and synthetic fuel production in the form of Power-to-Gas technologies and offshore wind power capacity. Results also indicate that 100% renewable energy-based domestic energy production can be achieved in Åland, with or without reliance on imported energy carriers, such as sustainable biofuels or electricity. A demonstration of a highly electrified transport sector may also offer Åland society several benefits outside of the boundaries of the energy system. New job creation related to renewable energy production on Åland could total between at least 3100 and 3900 job-years during manufacturing, construction and installation, and between 45 and 59 more permanent jobs related to operations and maintenance, depending on the scenario.