Power to Methane technologies through renewable H₂ and CO₂ from biogas: The case of Sardinia

Abstract

A Power-to-Methane system based on a Biological Hydrogen Methanation (BHM) process using the CO2 produced by a biogas upgrading process and the H2 produced by an alkaline electrolyser was analysed in this work. The electrolyser can be fed by the electrical energy produced by a dedicated PV plant or supplied by the electrical grid. The analysis of the energy production from the PV plant and the consumption of the electrolyser was carried out on an hourly basis considering different sizes for the PV plant and four different scenarios for the operating time of the electrolyser. Also, a preliminary economic analysis was carried out to estimate the levelized cost of biomethane (LCOBM) and the costs of biomethane transport with a dedicate pipeline and in form of LNG by trucks. Finally, the paper investigated the availability of biomass and biogas in Sardinia that can be converted into biomethane, and the contribution of BHM plants to supply the forecast demand of CH4. The availability of biogas in Sardinia, together with the production of biomethane through BHM systems, can supply up to 44% of the forecast demand of CH4.

Wood Ash Filter Material Characterization as a Carrier Material for Ex-Situ Biomethanation of Biogas in Biotrickling Filter Reactors

“…The methane content in raw biogas is 50-70 %, and the CO2 content is 30-50 % [1], [2]. Upgraded biogas with a CH4 content of up to 96 % can be injected directly into the natural gas grid [2]- [4]. The main convenience of biological biogas upgrading technologies is the modification of CO2 into high-value products, which fundamentally contribute to sustainable bioeconomics and life cycle economics [5], [6].…”

Design of a Multi-Tubular Catalytic Reactor Assisted by CFD Based on Free-Convection Heat-Management for Decentralised Synthetic Methane Production

“…The thermochemical CO 2 methanation process carried out via an exothermic Sabatier reaction (Equation ( 1)) is considered a competitive process to produce SNG at an industrial PtG scale [5]. Recently, the integration of this concept into existing decentralised CO 2 carbon stock plants, for example, biogas from municipal solid (e.g., food, wood, and yard) and liquid (e.g., sewage sludge) waste plants, has been explored to recycle biogenic CO 2 and increase renewable CH 4 production [6][7][8] as well as to reduce external energy dependency. However, the most challenging aspect for widespread SNG implementation is its economic competitivity, being more notable in PtG applications on a small scale.…”