Technical and economic analysis of the reconversion of an existing biogas plant to biomethane production: a case study.

The paper deals with the technical and economic analysis of a project aimed at transforming an existing plant, used for the anaerobic digestion of zoo-technical and agroforest biomass and including a CHP system of about 1 MW of electric capacity, into a facility producing bio-methane for automotive and/or stationary power applications. A comparison of different biogas upgrading technologies is performed, aimed at selecting the technology most appropriate to the size and typology of application under evaluation. Similarly, an analysis is performed to evaluate the opportunity of installing a bio-methane liquefaction facility, to simplify the management and transportation of the fuel, to be used in vehicles. The economic analysis is performed by considering the incentives presently available in Italy for bio-methane producers. Different scenarios are analyzed and discussed, and it was concluded that the conversion of the existing plant into a facility to produce bio-methane to be liquified and sold as fuel for vehicles represents at this moment a very attractive and profitable option.