Local energy projects have been associated with several benefits for the local community like social cohesion, economic gains, new skills, and environmental awareness. Yet, there is limited research on whether the projects fulfill their sustainability promises, and how the local community perceive the benefits. This research introduces a novel framework to assess the success of a local renewable energy project based on the perceptions of the local population and the initial ambitions of the projects. Using this framework two innovative local renewable energy projects are assessed; one in Tilos island in Greece and the other in El Hierro in Spain. An online questionnaire was used to assess the impact of the project on people's lives, their overall assessment of the project and their willingness to support similar future initiatives. The data show that the economic benefits are not significant when people assess the project, while on the contrary other factors like the environmental benefits, sense of pride, technical parameters institutional seem to have a greater effect. The environmental and institutional factors are also among the ones that influence people's willingness to support and participate in future projects. Overall, we reveal that the two projects are quite successful in the eyes of the local population and offer good case studies with several implications for policymakers and future initiatives.