It seems clear that energy production is one of the key aspects of global sustainability. Economic, social and environmental aspects must be taken into account in order to design appropriate policies and thus, multicriteria analysis becomes a very adequate tool to deal with real problems of this kind. This study was directed by the Regional Ministry of Environment of Andalucía, who wanted to know the impact on the cost and on the environmental damage of a potential mix, more focused on renewable sources. Some authorities of the Ministry acted as decision maker in the interactive process. As a result, we have built a linear multiobjective model, in order to determine the optimal electrical mix for the Spanish region of Andalucía. Namely, we determine how much electricity power should be installed and produced, by each of the eight generation systems considered (lignite, other coals, oil, natural gas, nuclear, photovoltaic, wind and mini-hydro). Apart from the economic criterion (yearly cost), we have considered the vulnerability (in terms of percentage of imported fuel) as a strategic criterion, and 12 environmental criteria, which have been derived using the Life Cycle Analysis method on the different production systems. The interactive system PROMOIN was used to solve the multiobjective problem. PROMOIN allows the decision maker to choose how to give preference information to the system, and enables changing it anytime during the solution process, which gives more flexibility to the decision maker and increases the confidence of the decision maker in the final solution. Copyright Sociedad de Estadística e Investigación Operativa 2014
