Physics / mechanism
BECCS combines biomass combustion or fermentation with carbon capture and storage to produce energy while achieving net-negative CO₂ emissions. Biomass absorbs atmospheric CO₂ during growth; combustion re-releases it; CCS intercepts that stream before atmospheric venting and injects it into geological formations. Key parameters: capture rate typically 85–95% of flue-gas CO₂, parasitic energy penalty 15–25% of gross output, storage capacity measured in Mt CO₂/yr per site. Current deployments are small—Drax (UK) pilots ~300 kt CO₂/yr captured; Illinois Industrial CCS captures ~1 Mt/yr from ethanol fermentation, the cleanest BECCS pathway because the CO₂ stream is near-pure. Techno-economic models require $60–200/tonne CO₂ to be competitive depending on biomass cost and transport to storage.
Competitive landscape
Direct air capture (DAC) competes directly for the “net-negative” mandate with lower land footprint but higher current cost (~$300–1000/t CO₂). Enhanced weathering and ocean alkalinity enhancement are earlier-stage alternatives. Point-source industrial CCS on cement or steel competes for the same geological storage infrastructure and policy credits. Bioenergy without CCS is a substitute where carbon accounting is lax.
Companies using
Connected ideas
Sources
Frontier (open questions)
- To be added.