Póster presentado en ESCAPE-21, 21st European Symposium on Computer‐Aided Process Engineering, May 29-June 1, 2011, Chalkidiki, Thessaloniki, Greece. This work introduces a systematic method for the optimization of absorption cycles by combining the capabilities of simulation packages and optimization tools, including the Life Cycle Assessment (LCA). The case presented is a multi objective mixed-integer nonlinear programming (moMINLP) problem that is decomposed following the outer-approximation schema. The primal level entails the solution of the nonlinear programming (NLP) subproblem, where the binary variables are fixed. The master is a specially tailored mixed integer linear programming (MILP) problem. The NLP subproblems are solved by combining gradient-based NLP solvers (i.e., fmincon) linked with rigorous process simulation (Aspen Plus®). The methodology is tested using an absorption cooling system. The results obtained and the corresponding Paretto Curves of optimal design show that the objective function can be significantly reduced with the presented methodology. Financial support from the Consellería de Educación of the Generalitat Valenciana (BEST/2010/085) and Ministerio de Ciencias e Innovación (PPQ, CTQ2009-14420-C02-02).