A new and systematic procedure to select and size a polygeneration plant fuelled by natural gas, solar energy and gasified biomass is presented in this paper The proposed procedure is based on the superstructure definition containing a long list of possible configurations for a polygeneration plant simultaneously producing electricity heat cold and fresh water Based on that superstructure a mathematical programming model was developed and applied to a Spanish tourist resort Three key aspects were optimized in the mathematical programming problem energy savings greenhouse gases (GHG) emission reduction and economic feasibility The results show firstly that the simultaneous production of electricity heat cold and fresh water is reliable upon the established assumptions Secondly that today higher economic profitability is yet achieved with only natural gas-based technologies although higher energy savings and GHG reduction are obtained through the gradual increase of renewable energy sources (C) 2010 Elsevier Ltd All rights reserved