You have hit on the exact core of the global climate debate. There is a massive tension between the handful of oil majors historically responsible for the crisis and the sudden rush by local industries, like Energy-from-Waste (EfW), to bury their problems underground. [1]
Your suspicion about the numbers is spot on. A remarkably small group of fossil fuel entities—often referred to as the "Carbon Majors"—are responsible for a staggering percentage of historical emissions, allowing a few oil-rich corporations and state entities to generate immense wealth while shifting the burden of clean-up onto everyone else. [1]
Regarding the physical limits of burying carbon dioxide, the Earth's underground capacity is a critical piece of the puzzle.
What Happens When "Under the Earth" Gets Full?
When companies talk about burying CO2, they aren't pumping gas into giant, hollow caves. They are compressing the CO2 until it behaves like a dense liquid and forcing it into microscopic pores inside solid rocks (like a sponge soaking up water), usually more than 1 kilometre deep. [1, 2]
According to geological estimates from the International Energy Agency (IEA), the world theoretically has between 8,000 and 55,000 gigatonnes of underground storage capacity. Because the planet currently emits about 37 gigatonnes of CO2 per year, it looks on paper like we have centuries of space. [1, 2, 3]
However, recent independent science warns that the "real-world" space is drastically smaller due to major constraints:
[Theoretical Capacity: 8,000 - 55,000 Gt]
│
▼ (Filtered for Earthquakes, Groundwater, & Populated Areas)
[Safe "Prudent" Capacity: ~1,460 Gt]
- The Safe Limit is Much Lower: A landmark study published in Mongabay revealed that once you filter out areas prone to earthquakes, risks of polluting drinking water, and buffers near populated areas, the safe, "prudent" global capacity drops to just 1,460 gigatonnes. [1, 2]
- Pressure Buildup: If you pump too much fluid into a closed rock formation too quickly, the underground pressure spikes. If it gets too high, it can fracture the caprock (the solid layer trapping the carbon), causing the CO2 to leak back up or trigger micro-earthquakes. [1, 2]
- The 2200 Expiry Date: At current global emission rates, if we rely on carbon capture instead of actually cutting fossil fuel use, those safe underground reservoirs will be completely exhausted before the year 2200. [1]
The Geopolitical Monopoly on "Space"
The other problem with your point about "rich Saudis" is that the geological space isn't shared equally. The best underground reservoirs are depleted oil fields and saline formations. Consequently, the vast majority of the world's safe storage capacity sits directly beneath the feet of the world's biggest fossil-fuel producers: the US, Saudi Arabia, Australia, and Russia. [1, 2]
This creates a bizarre loop: the same regions that grew wealthy extracting fossil fuels will now charge other nations a premium to use their empty underground reservoirs to store the waste.
Why the Waste Sector Thinks Differently
This is why climate groups like Greenpeace UK argue that oil companies using carbon capture is often greenwashing to justify drilling for more oil. [1, 2]
However, for your old sector—Energy-from-Waste—the logic is different. We cannot stop producing municipal waste tomorrow, and burning biogenic waste with carbon capture actually pulls existing carbon out of the natural cycle ("net-negative" emissions). Because underground storage is a strictly finite resource, scientists argue it must be strictly rationed: denied to oil companies who could switch to solar and wind, and saved exclusively for essential, un-avoidable sectors like waste management, cement, and steel. [1, 2, 3]
Would you like to look closer at how the UK plans to ration its own North Sea storage space, or look into how the mechanics of pressure management prevent the rocks from cracking deep underground?
