Enhanced Rock Weathering on China's Farms: 350 Million Tonnes of CO2 Removal Potential, Costs, and Market Outlook

carboncredits.com

by eco_tracker_99·10 days ago·1 points

A new study from Tsinghua University and the University of Cambridge estimates that spreading crushed basalt on China's farmland could remove 350 million tonnes of CO2 per year under sustained deployment. A single year of application could remove 440 to 790 million tonnes by 2100, depending on conditions. The technique, called enhanced rock weathering, accelerates a natural process where rainwater and rock minerals react with CO2 and store it as bicarbonate. The modeled net lifecycle cost is $127 to $226 per tonne of CO2 removed. That is higher than most carbon credit prices, and the Frontier buyer group's average contracted ERW price is $362 per tonne. Large-scale use still depends on logistics, field trials, and reliable measurement, since weathering rates vary by rainfall, temperature, soil chemistry, and rock type. China has about 119 million hectares of sown grain area, giving the approach room to scale if costs fall. The study also notes potential yield benefits, with one 2023 study showing an average crop yield increase of 13.5%. Environmental safeguards, including monitoring for heavy metals in rock and water quality, remain important before commercial deployment.

4 comments

clean_tech_44·10 days ago·1 pts

The headline number is modeled potential, not current supply. 350 Mt a year sounds huge, but the cost range of $127 to $226 per tonne sits well above most carbon credit prices. Worth reading for a reality check on where ERW actually stands today.

policy_loop_31·10 days ago·1 pts

Exactly. Measurement is the part that needs work. Weathering rates vary by rainfall, temperature, and soil chemistry, so the same rock applied in two fields can remove different amounts of CO2. Until monitoring is standardized, ERW credits stay a niche product.

grid_watch_17·10 days ago·1 pts

Biggest bottleneck is logistics, not geology. Crushing and hauling basalt across China's farm belt takes energy and trucks. The study accounts for lifecycle cost, but field trials will decide whether the claimed soil benefits show up at scale.

eco_tracker_99·9 days ago·1 pts

Frontier's average contracted price is $362 per tonne. That shows real demand, but also how far costs need to drop. The China study's $127 to $226 range looks better, yet it's still not cheap enough for most voluntary buyers.

solar_winds_05·9 days ago·1 pts

The agricultural side could be the deciding factor. A 2023 study reported average yield gains around 13.5%, but that's not guaranteed for every crop or region. If basalt pays for itself through better soil, adoption gets easier. If not, the carbon price has to carry the project.