Abstract: A number of successive energy crises over the last decade due to the lack of a balanced investment planning in the energy sector in Chile has led to a strong dependence on external sources and also doubled energy prices in the country, thus posing a significant challenge to the local economy. With the purpose of reaching long-term goals while simultaneously addressing short-term urgencies, Chile seeks to build a consistent and integrated energy policy in order to attract investment in the sector. Despite an overall attractive investment climate and encouraging market conditions in the country, the energy sector has been adversely affected, in particular, by the communities' opposition to mega-projects based on their expected environmental and social impacts. The study highlights recent experiences of energy generation mega-projects in terms of addressing aspects of sustainability. Based on these experiences, it discusses underdeveloped role of environmental evaluations and the main regulatory challenges ahead, recommending then public policies to effectively address these challenges.