Thread by @geoengineering1

🚨Many climate models assume large-scale Bioenergy with Carbon Capture and Storage (#BECCS) will help limit global warming. But a new study by @PIK_Climate shows that if we respect planetary boundaries, BECCS potential is far lower than expected. 🧵1/8

2/ BECCS involves planting fast-growing crops, burning them for energy, capturing the CO₂, and storing it underground. While this sounds like a promising carbon removal method, large-scale deployment could disrupt ecosystems and strain natural resources.

3/ The study looked at how much CO₂ BECCS could remove without crossing planetary boundaries (PB). It considered 4 key limits:

1⃣ Fertilizer (Nitrogen) use – Too much nitrogen harms soil & water

2⃣ Freshwater availability – BECCS needs water, but so do people & ecosystems

3⃣ Deforestation limits – Expanding BECCS can’t come at the cost of forests

4⃣ Biodiversity protection – Wildlife & ecosystems must be preserved

4/ When these boundaries are not considered, BECCS could theoretically remove billions of tons of CO₂/yr. But respecting them reduces BECCS potential to <200 MtCO₂/yr by 2050 (outside current farmland). This is far below the ~7.5 GtCO₂/yr assumed in many climate scenarios.

5/ The biggest limiting factor? Biodiversity protection. Avoiding further loss of biosphere integrity reduces BECCS potential by 93%. Other constraints have major impacts too:
➖ Nitrogen limits: -21%
➖ Freshwater protection: -59%
➖ Deforestation limits: -61%

6/ This means that "if we want BECCS to play a major role in carbon removal, we’d need to use existing agricultural land. That’s only possible if we change our food system—reducing land-intensive animal agriculture to free up space," says the researchers.

7/ The study highlights a key trade-off: "climate action must not come at the cost of ecosystem stability. Relying too much on BECCS could push us further beyond Earth’s critical limits, worsening long-term risks," the study concluded.

📝 For more details, read the study entitled "Multiple planetary boundaries preclude biomass crops for carbon capture and storage outside of agricultural areas" here:


#BECCS #CDR

🧵8/8nature.com/articles/s4324…

"Unroll" @threadreaderapp