A novel hybrid plant for the production of a mixture of methane and hydrogen (17 vol%) from a steam-reforming reactor whose heat duty is supplied by a concentrating solar power (CSP) plant by means of a molten salt stream is here presented. It has been demonstrated in the literature that mixtures containing up to 17 vol% of hydrogen in a natural gas (NG) stream can be sent in the NG pipeline infrastructure and can supply NG-ICE propulsion systems reducing the GHG emissions and improving the engine efficiency. A rigorous two-dimensional model has been developed to investigate the behaviour of the steam-reforming reactor and the effects of some important operating conditions, such as the reactant mixture residence time, the steam-to-carbon ratio in the feedstock, the operating pressure and the inlet temperature. The final outcome of this work is the dimensioning of a solar enriched methane plant for the electricity and gas requirements of domestic users. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.