Work

Direct biogas methanation via renewable-based Power-to-Gas: Techno-economic assessment based on real industrial data

Year: 2025

Type: article

Abstract: • Solar electricity-assisted industrial biogas methanation is investigated. • Batteries, compressed H 2 , or their combination are used as solar energy storage. • Compressed H 2 storage ensured the lowest production cost of methane (1.1 €/Sm 3 ). • A 40 MW photovoltaic park is required for optimized methanation of 800 Nm 3 biogas /h. • H 2 production/storage capital cost reduction is required for economic feasibility. This paper presents a design and techno-economic assessment of different Power-to-Gas configurations based on direct biogas methanation and renewable electricity. The proposed concept integrates the anaerobic digestion of organic waste with the methanation of carbon dioxide using green hydrogen. Yearly data of an anaerobic digestion process operating at the industrial scale were considered. The methanation unit was designed through two cooled fixed-bed reactors in series; the first had 14 parallel tubes that were 2.5 m long, and the second one had 18 tubes (each one 1.5 m long). A global carbon dioxide conversion above 98 % occurs in the unit, ensuring an outlet composition suitable for injection into the natural gas distribution grid. Different options for energy storage were thus considered; hydrogen storage in pressurized tanks (‘Buffer’), electrochemical storage in batteries (‘Battery’), and a hybrid combination of the two systems (‘Hybrid’). A ≈40 MW photovoltaic park provided the required energy input. The configuration with hydrogen storage tanks was established as the most promising option based on current trends, medium-term, and target projections scenarios of capital costs. These three cost scenarios led to a synthetic natural gas (SNG) production cost range of 2.3–4.2, 1.6–2.9, and 1.1–2.0 euros per cubic meter, respectively. This configuration requires a ≈35 MW electrolysis unit and about 100 tons of hydrogen storage capacity. Considering the current methane price, results indicate that current capital costs of photovoltaics, electrolysis, and H 2 storage still represent an obstacle to overcome, before achieving the profitability of the concept.

Source: Energy Conversion and Management

DOI: 10.1016/j.enconman.2025.119775

Authors: Emanuele Giglio, Micaela Bianco, Giuseppe Zanardi, Enrico Catizzone, Girolamo Giordano, Massimo Migliori

Institution: University of Calabria

Language: English

Topic: Hybrid Renewable Energy Systems

Subfield: Energy Engineering and Power Technology

Field: Energy

Domain: Physical Sciences

SDGs: Affordable and clean energy, Climate action, Industry, innovation and infrastructure, Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $4,600