The transition towards a sustainable energy mix is required to achieve Sustainable Development Goal 7 for affordable and clean energy. Remote islands not connected to grid which depend on diesel generators may appear ideal because they can benefit from a variety of renewable energy sources. However, renewable energy deployment requires a lifetime perspective to not inherit waste and other problems to future generations. The aim of this paper is to present a life cycle sustainability framework developed and applied for the case of the island of Ushant off North West France. Seven renewable energy generation scenarios were examined and assessed using technoeconomic, social and environmental indicators utilising life cycle costing and life cycle assessment modelling. The results show that only three out of the seven examined renewable energy scenarios manage to cover the 6,807 MWh per annum demand. These scenarios can improve all the indicators against the business-as-usual diesel generation scenario except the ones related to toxicity and reduce greenhouse gas emissions by more than 92%. The easy-to-use framework allows the users to adjust their scenarios and receive useful insight about the nature of the trade-offs between the various indicators. It can also be adapted and updated to include more technologies and support the investigation of more sustainable energy scenarios of other remote island cases in the future.