Just the 64,000 years
Direct Air Capture
Studies suggest that removing one billion tons of CO₂ using DAC could require around 1,200 terawatt-hours of energy. For example, one DAC plant can capture 1.1 Mt-CO₂ annually, requiring 5.24 GJ of heat and 343 kWh of electricity per ton of CO₂ captured.
To calculate the total energy required to extract 1 trillion tonnes (1,000,000,000,000 tons) of CO₂ from the atmosphere, we'll break it down into electrical energy (kWh) and thermal energy (GJ).
Given:
- Electrical energy per ton = 343 kWh
- Thermal energy per ton = 5.24 GJ
Step 1: Calculate Total Electrical Energy
Total Electrical Energy = 343 kWh/ton × 1,000,000,000,000 tons
= 343 × 10¹² kWh
= 343 trillion kWh
Step 2: Calculate Total Thermal Energy
Total Thermal Energy = 5.24 GJ/ton × 1,000,000,000,000 tons
= 5.24 × 10¹² GJ
= 5.24 trillion GJ
Step 3: Convert GJ to kWh (Optional, for comparison)
Since 1 GJ ≈ 277.778 kWh, we can convert thermal energy to kWh:
5.24 × 10¹² GJ × 277.778 kWh/GJ
≈ 1.456 × 10¹⁵ kWh
= 1,456 trillion kWh
Total Combined Energy (in kWh equivalent):
343 trillion kWh (electric) + 1,456 trillion kWh (thermal)
= 1,799 trillion kWh
Summary:
- Electrical energy required: 343 trillion kWh
- Thermal energy required: 5.24 trillion GJ (or ~1,456 trillion kWh)
- Total energy (kWh equivalent): ~1,799 trillion kWh
For context, global electricity consumption in 2023 was about 28,000 TWh (28 trillion kWh). This means the energy required for 1 trillion tons of CO₂ extraction is equivalent to ~64 years of global electricity consumption (if considering only electrical energy) or ~64,250 years if considering the thermal energy in kWh terms (though thermal energy is typically cheaper than electricity).
This highlights the immense scale of energy needed for large-scale CO₂ removal.
If you are wondering where the 1 trillion tons came from that's what is required to get us back down to pre-industial levels of CO₂ in the atmonsphere.
And if you are thinking well don't worry I'm sure we'll improve the technology. Processing the atmosphere is not like packing more and more chips into a smaller and smaller space. There is no chance of improving the technology at computing sorts of speed especially when we are spending so little on it!