Technology atlas / Catalytic hydrogenation
CO₂ methanation
The Sabatier reaction combines CO₂ with hydrogen over a nickel or ruthenium catalyst to make synthetic methane.
Technical reference · Updated 2026-10-10 · No current-news claim
Where the carbon goes
Carbon returns to the atmosphere when the fuel is combusted, typically within months to a few years of production.
Conceptual process flow · left to right
- 01CO₂ + H₂ feed
- 02Methanation reactor
- 03Heat recovery
- 04Water removal
- 05Gas upgrading
- 06Grid injection
From chemistry to process
- Feedstocks
- CO₂ or biogas CO₂, Hydrogen
- Products
- Synthetic methane, Water, Process heat
- Catalysts
- Nickel-based catalysts; ruthenium for some applications
- Conditions
- Catalytic route typically operates at a few hundred °C with active heat removal; biological methanation operates near ambient temperature with methanogenic archaea.
Performance & demonstrated scale
Power-to-gas plants have been built at various scales; operating hours and measured output must be verified per site.
2.743 t CO₂/t CH₄ theoretical
0.503 t H₂/t CH₄ theoretical
Economics
Hydrogen supply dominates. Roughly half the hydrogen ends up as water, so energy efficiency from electricity to methane is lower than for some other e-fuels.
Climate considerations
Methane slip along the chain can erode benefits; electricity carbon intensity and CO₂ origin determine the result.
CCU Reality Check · pathway assessment
What remains to be demonstrated?
This initial assessment separates process knowledge from the evidence needed for a commercial conclusion. Missing information is left unresolved.
| Dimension | Assessment and evidence gap |
|---|---|
| CO₂ feedstock availability | No site-specific supplier, volume, purity guarantee or delivery contract has been verified. |
| Capture and delivered cost | Not quantified. Capture, conditioning, compression and transport need separate boundaries. |
| Energy and hydrogen demand | Theoretical stoichiometric or thermodynamic values are shown above. Actual process energy and feed losses remain scenario assumptions. |
| Catalyst and reactor performance | Nickel-based catalysts; ruthenium for some applications. No plant lifetime or sustained performance is verified here. |
| Product separation | The process flow identifies separation stages where relevant; a quantified separation duty and cost remain unavailable. |
| CAPEX and OPEX | No plant-specific capital estimate or complete operating-cost dataset is attached. |
| Minimum selling price | Not calculated. Capital recovery, utilization, financing and a complete operating boundary are required. |
| Fossil benchmark competitiveness | No verified regional benchmark comparison. Calculator benchmark values, where shown, are illustrative. |
| Climate performance | Methane slip along the chain can erode benefits; electricity carbon intensity and CO₂ origin determine the result. |
| Scale-up bottlenecks | Hydrogen cost and electrolyser utilisation; Heat management of the exothermic reaction; Catalyst sensitivity to sulphur and other impurities; Competes with low-cost natural gas. |
| Customer and offtake readiness | No qualified-customer or executed-offtake evidence is attached to this pathway profile. |
| Policy dependence | Not assessed for a specific project or jurisdiction. Do not assume subsidies or certification eligibility. |