Cost

Carbon Capture Cost Estimation and CO2 Compression Quoting

What actually drives cost per tonne of captured CO2, how to build the quote bottom up, and the estimating errors that quietly wreck margins.

Cost is best expressed as levelized cost of capture per tonne CO2, which for post-combustion amine plants runs 45 to 100 dollars per tonne on natural gas flue gas and 40 to 70 dollars on higher concentration coal or cement streams. Direct air capture sits far higher at 250 to 600 dollars per tonne. Build the number from four buckets: energy, consumables, capital recovery, and labor plus maintenance. Energy alone is 40 to 60 percent of operating cost, so quote it first. The Regeneration Heat Load and CO2 Compressor Power outputs are your two largest cost line items before you touch anything else.

Price the steam and power explicitly. At 3.6 GJ per tonne and steam at 6 dollars per GJ, regeneration costs 21.60 dollars per tonne captured. Compression at 100 kWh per tonne and 0.07 dollars per kWh adds 7.00 dollars. Blowers and pumps add another 25 to 40 kWh per tonne, or 2 to 3 dollars. That stacks to roughly 31 to 33 dollars per tonne in energy before consumables. Use the Blower Energy Cost and Solvent Makeup Cost calculators to keep these current, because a 1 dollar per GJ swing in steam price moves levelized cost by about 3.60 dollars per tonne.

Consumables are smaller but easy to underestimate. Amine makeup at 1.5 kg per tonne and 2.20 dollars per kg of MEA is 3.30 dollars per tonne; specialty solvents at 8 to 15 dollars per kg push that to 12 to 22 dollars per tonne, which surprises estimators who assumed generic pricing. Add caustic and activated carbon for reclaiming at 1 to 2 dollars per tonne, plus cooling water makeup. Solid sorbent replacement, at 30 to 50 dollars per kg for structured amine media on a 3 year life, can dominate a DAC quote outright. The Sorbent Consumption calculator turns life and cycles into annual dollars.

Capital recovery converts installed cost into a per tonne charge. A 100,000 tonne per year post-combustion unit might carry 60 to 120 million dollars installed. At an 8 percent discount rate over 20 years, the capital recovery factor is 0.1019, so 90 million dollars becomes 9.17 million dollars per year, or 91.70 dollars per tonne at full capacity. Drop utilization to 80 percent and that jumps to 114.60 dollars, because capital charges do not scale with output. This is why capacity factor, not equipment price, is the single biggest lever in most capture quotes, and the first thing a client should challenge.

Labor and maintenance round out opex. Estimate fixed maintenance at 3 to 4 percent of installed capital per year, so 90 million dollars implies 2.7 to 3.6 million dollars annually, near 30 dollars per tonne at 100,000 tonnes. Operating labor for a bolt-on capture island runs 4 to 8 shift positions plus supervision, roughly 0.6 to 1.2 million dollars per year. Together these often equal the entire energy bill, yet many quotes fold them into a vague overhead percentage. Break them out so a client can interrogate each line and so you can defend the total when the numbers get questioned.

Build the quote bottom up: captured tonnes, then energy per tonne, consumables per tonne, capital recovery per tonne, and fixed opex per tonne. For our example that is roughly 32 plus 5 plus 92 plus 33, or about 162 dollars per tonne at 80 percent utilization, before any CO2 transport and storage fee of 10 to 30 dollars per tonne. Sensitivity matters more than precision: show the client the number at 70, 80, and 90 percent utilization and at plus or minus 20 percent steam price. A single point estimate invites disputes the first month the plant underperforms.

Estimates go wrong in predictable places. Teams size energy on solvent vendor lab duty and ignore a 10 to 15 percent field penalty from heat exchanger fouling, which the Heat Exchanger Fouling Loss calculator quantifies. They forget CO2 losses to venting and slip, 1 to 3 percent, so they bill fewer tonnes than the capital was charged against; the CO2 Leak Loss calculator catches that gap. And they quote nameplate capacity while the plant actually runs 75 percent, understating cost per tonne by 20 percent or more. Always reconcile the tonnes you bill against the mass balance from Capture Efficiency before you sign.

Published 2026-07-02.