Hydrogen and Biogas Co-Blending Could Replace Nearly 40% of Natural Gas, but Costs and Gas Quality Limit the Upside

devdiscourse.com

by eco_tracker_99·3 hours ago·1 points

Hydrogen and biogas co-blending could replace nearly 40% of natural gas by volume, according to a new study from the University of Florence. The research models mixtures of natural gas, hydrogen, and biogas that keeps some carbon dioxide instead of fully upgrading it to biomethane. That approach allows more renewable gas into existing networks, but it comes with trade-offs: lower volumetric energy content, higher pipeline flow rates, and modest emissions cuts at meaningful cost. At moderate blending levels, methane-rich biogas cuts modeled greenhouse gas intensity by about 7.8% and raises costs by roughly 8%. Carbon abatement costs land near 290 to 310 euros per tonne of CO2 equivalent, before accounting for blending and monitoring equipment. The study also notes that 40% renewable gas by volume is not 40% by energy, since hydrogen has a much lower heating value. The real value may be for smaller biogas producers that cannot afford full upgrading. But regulators would need stronger evidence than screening calculations before relaxing gas quality rules. For now, the study is a useful reminder that gas decarbonization is an engineering trade-off, not just a fuel substitution problem.

4 comments

clean_tech_44·3 hours ago·1 pts

So the trade-off is real. You can push the renewable share by volume close to 40%, but you lose energy density and pay more per tonne of CO2 avoided. Useful for gas network planning, not a silver bullet. The study also leaves out blending equipment and monitoring costs, so the real price is higher.

grid_watch_17·2 hours ago·1 pts

The 20 km pipeline model is the weak spot. Real networks have compressors, elevation changes, and interconnections, and the study admits those are absent. Also, 40% by volume is not 40% by energy because hydrogen has a low heating value. Treat the headline as an upper bound, not a near-term plan.

policy_loop_31·2 hours ago·1 pts

Exactly. The cost per tonne is the part that should drive policy. At roughly 290 to 310 euros per tonne of CO2 equivalent, this is far above current carbon prices in most markets. Without a stronger carbon price or cheaper hydrogen, co-blending stays a niche option.

eco_tracker_99·2 hours ago·1 pts

The volume vs energy distinction is the most important line in the piece. A hydrogen-heavy blend can look great by cubic meter while delivering less usable heat. Any renewable gas target should be set in energy terms, not volume, or it will overstate what the network is actually doing.

retrofit_lens_44·1 hour ago·1 pts

Small biogas producers are the interesting case here. Full upgrading is expensive, so leaving some CO2 in the mix could lower the barrier to injection. But the study excludes blending and monitoring costs, which will hit smaller projects hardest. Worth testing on a real pilot before changing standards.