The fragile ecosystem of the Galapagos Islands is being affected by population growth, intensive tourism, the exploitation of local resources and the high consumption of imported fossil fuels. This unsustainable development model makes the provision of services such as electricity a challenge. This research investigates the hybrid renewable mini-grid Baltra–Santa Cruz, which represents 62% of the electricity generation mix of the archipelago. This study aims to support the Galapagos Zero Fossil Fuel Initiative and the Sustainable Development Goal 7 through the reduction in diesel consumption and electricity generation costs. To do so, HOMER Pro, a specialized hybrid renewable mini-grid planning tool, is used to perform several techno-economic assessments, focusing on different electricity demand scenarios. Therefore, multiple pathways are compared to identify the most reliable alternatives towards the progressive decarbonization of this hybrid system. The results indicate that installing 18.25 MWp of photovoltaic and 20.68 MWh of battery capacity could reduce the Levelized Cost of Electricity (LCOE) from 32.06 to 18.95 USc/kWh, increasing the renewable energy (RE) share from 18% to 39%. Additionally, the successful application of energy efficiency measures would even reduce the LCOE to 17.10 USc/kWh. What is more, distributed energy is considered the most attractive way to involve islanders in the energy transition process. Finally, this paper offers a comprehensive business model proposal to achieve a resilient energy supply, based on a combination of auctions and energy community models, which demands high political will, reliable and innovative regulations and social awareness about energy use.