This paper describes and compares the results of thermodynamic and economic modelling based on integrating an existing large size steam power plant (ENEL’s Brindisi power plant-660 MWe) with hydrogen production and purification plants. ENEL is one of the main Italian power utility. The high quality of the hydrogen produced would guarantee its usability for distributed generation (e.g. by micro gas turbine, Stirling engine, fuel cell, etc.) and also for public transport (using PEM fuel cells).The proximity of a hydrogen production and purification plant to an existing steam power plant could favourite connections in terms of energy requirements exchange; moreover the complete systems proposed could represent an attractive approach to flexible co-production of hydrogen and electricity.Two different technologies for the syngas production section are considered: the pyrolysis process and direct pressurised gasification. These technologies produce syngas with different characteristics in terms of temperature, pressure and composition: this has a profound effect on the layout of the complete systems proposed in this paper. The model for the pyrolysis process is based on an existing 800 kWt coal – and biomass – fed pyrolysis ENEL’s plant placed in Bastardo (Perugia, Italy): a detailed model of the plant was created.Different coals (Ashland, South Africa, Sulcis) and biomass (poplar, mischantus, wood residuals, husks) are considered in this study in order to explore the real potential of mixed-fuel in terms of thermodynamic performances and costs.The results were obtained using WTEMP software, developed by the Thermochemical Power Group of the University of Genoa, showing the performance attainable by supplementing an actual steam power plant with systems for hydrogen production and purification for a novel vision of clean distributed power generation and public transport.
