La Prospective is an appropriate approach for contexts distinguished by high uncertainty and social conflict. This French scenario building method has received limited attention in the field of energy resources planning, especially beyond approaches focused on technological issues. The paper utilized the La Prospective method to generate strategic 2050 visions, integrating energy resources and spatial development. The Araucania region in Chile served as a case study, engaging 52 stakeholders, both experts and members of the public. The method was implemented in three stages: (a) system assessment; (b) understanding the dynamics of the system; and (c) obtaining strategic future visions. The results show a regional vision based on key concepts: (i) affordable electric power that protects the environment and clean air; (ii) preference for individual self-generation and/or collective systems (iii) digitally connected and available to everyone. The paper closes with a discussion on how participatory processes enable the elaboration of strategic futures based on high levels of consensus among stakeholders with different interests and professional backgrounds and provides a few recommendations for future research.