Direct Air Capture Sorbent Productivity Calculator

Compute sorbent productivity as the annual tonnes of CO₂ captured per tonne of active sorbent. Adjust uptime and capture efficiency to stress-test process designs, commissioning targets, and replacement strategies.

Total active sorbent mass charged in the DAC contactors, in metric tonnes.
Average hourly CO₂ captured across all contactors, measured in tonnes per hour.
Leave blank to assume 90% uptime; otherwise enter actual annual availability.
Fraction of the gross capture rate that survives vent losses and slip; default is 95%.

Calculator ignores ramp transients, bed-to-bed imbalances, and degradation of working capacity over time.

Examples

  • Inventory 15.0 t, capture rate 2.80 t/h, 92% capacity factor, 96% efficiency ⇒ productivity ≈ 1,445.31 t CO₂ per t sorbent-year
  • Inventory 8.5 t, capture rate 1.10 t/h, default 90% capacity factor, 88% efficiency ⇒ productivity ≈ 898.13 t CO₂ per t sorbent-year

FAQ

Why normalise capture by sorbent mass?

Normalising by sorbent mass reveals how hard the material is working and whether contactor design or regeneration limits are leaving capacity idle. It helps compare vendors that propose different working capacities or cycle designs.

How should I set the capacity factor?

Base it on expected annual operating hours after deducting scheduled maintenance, freeze protection downtime, and grid curtailments. Pilot plants may run below 50%, while commercial arrays targeting tax credits typically exceed 85%.

Does the calculator include regeneration energy limits?

No. It assumes the stated capture rate already reflects steam, electrical, or vacuum constraints. If energy limits reduce throughput, lower the capture rate or capture efficiency to reflect the bottleneck.

What if sorbent inventory changes during the year?

Update the input to the average active inventory over the reporting period or break the year into segments and weight each productivity result by its duration before averaging.

Additional Information

  • Productivity is annual CO₂ captured divided by installed sorbent mass, so the unit is tonnes of CO₂ per tonne of sorbent per year.
  • Capacity factor converts downtime, maintenance, and weather stoppages into annualised operating hours (8760 × CF).
  • On-stream capture efficiency derates the nominal rate to reflect slip, breakthrough, or blower bypass losses.
  • The model assumes sorbent inventory is steady-state; update the input if large campaigns replace media mid-year.

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