Because the alternative is deep and rapid emissions cuts which countries are unwilling to implement, the IPCC now assumes that stabilizing the climate will involve heavy use of negative emission technologies: “between 100bn and 1trn tonnes of CO2 to be removed from the atmosphere by the end of the century if the Paris goals were to be reached; the median value was 730bn tonnes–that is, more than ten years of global emissions.”
There are numerous possible options. CO2 could be separated from flue gasses from power plants, compressed, and injected underground. If those power plants burn biomass which recently took CO2 out of the atmosphere, that could help draw down the stock of carbon in the atmosphere. That approach is called bioenergy with carbon capture and storage or BECCS. It’s also possible to separate CO2 directly from the air and bury it (direct capture). It’s also worth bearing in mind that sometimes CO2 is injected underground to push up oil to be sold (enhanced oil recovery or EOR). In that case, it likely creates more emissions than it avoids since the same volume of oil is pushed out and then likely burned in a vehicle where it cannot be captured.
All this may be highly questionable as a climate change solution and, indeed, the main push for CCS is from corporations and states that don’t want to give up fossil fuel production. The notion the technology will eventually exist at scale helps justify today’s fossil fuel burning, even though right now we’re buying about 40 million tonnes of CO2 while emitting 43.1 billion tonnes. Burying any substantial fraction of global CO2 emissions would mean compressing and burying many times the total quantity of oil we take out of the ground — with everything that implies about costs, deployment times, and capital requirements — and this whole infrastructure would require energy to run instead of producing it, either requiring us to deploy yet-more climate-safe energy to build and power the equipment or putting us in the self-defeating position of burning more fossil fuels to generate energy to bury the CO2 from the fossil fuels we already burned.
Related:
- Betting on a long shot
- Oceanic dumping of CO2
- Hot Air
- Cleaner coal
- FutureGen and the cost of CCS
- Taskforce calls for $2 billion for CCS
- Will technology save us?
- Crystals for improved CO2 separation
- GHG-intensive industries and regulation
- Romm’s fourteen wedges
- Selling ‘clean coal’
- CCS skepticism
- Spremberg clean coal plant
- Pick your poison: nuclear or ‘clean coal’
- The geological plausibility of CCS
- CCS plan subverted by local opposition
- Gore on CCS
- Technology silver bullets for climate change
- Tackling coal emissions
- The Energy Gang on “clean coal”
- Advanced physics for carbon removal
- Dyson’s carbon eating trees
- Alternative to a carbon tax: carbon deposit
- Some carbon capture and storage numbers
- Monbiot on British carbon capture plans
- Air travel and carbon capture
- Carbon capture in Saskatchewan
- Some carbon capture similes
- Greenpeace on carbon capture and storage
- Carbon capture research
- The GAO on carbon capture and storage
- Carbon capture cannot redeem the oil sands
- A responsible position on carbon capture
- Carbon capture and storage (CCS), always around the corner

