jats:pThe energy crisis and the exacerbation of climate change, along with the associated geopolitical tensions, including the war in Ukraine, are accelerating the energy transition in Europe. A transition from fossil energy sources to renewable energy sources that have a low Energy Return Rate, involves, among many other issues, the use of wide areas to locate the necessary infrastructure for production, transport and storage, altering territories with agricultural, cultural and ecological values. This process is based on the deployment of renewable energy megaprojects in peripheric areas of the continent, mostly in the southern states creating a wide range of social conflicts and resistances. We analyse this process in the case study of the province of Granada, a peripheric territory of south-east Spain considering the category of energy colonialism and the six dimensions that characterise it, arguing that this is a proper approach to address internal colonialism related to the corporate energy transition. We also want to demonstrate the importance of using participatory methodologies for this analysis, so we have developed an online survey, semi-structured interviews and participatory cartography workshops, always focusing on the citizens and stakeholders who are resisting the deployment of renewable energy megaprojects in the province of Granada. The obtained results allow us to confirm the necessity of using participatory methodologies and the colonial aspect of this deployment, including the characteristics of social resistance, the territorial impacts, the land-grabbing process and the inequalities in the production, distribution and use of energy. We conclude with the need to articulate a decolonial energy transition where participatory methods constitute a fundamental tool both to attend the resistances and to build the alternatives.</jats:p>