Table 2 Estimated capital expenditures (CAPEX) for the MgO looping process.

From: Ambient weathering of magnesium oxide for CO2 removal from air

CAPEXCost [M$]Comments
Lower boundUpper bound
Raw mineral8,760110,376Lower bound: Estimated based on open pit mining cost ($10 tonne−1)75 and inflated to represent the required size reductions. Upper bound: cost of calcined magnesia76.
Air separation unit and condensera7852,260Lower bound: scaled from Keith et al. installed calciner cost20. Upper bound: scaled from NASEM Report (built-in installation costs)7.
Oxy-fired calcinera93012,202Lower bound: Scaled from Keith et al.20. Upper bound: Scaled from NASEM Report (Built-in 4.5× factor for new technology)7.
Land1291,796Lower bound: Pasteur farm real estate at $1390 per acre. Upper bound: Farm real estate at $6430 per acre54.
Transportation (Conveyor System)a1291050Price from mining cost data46,77. Lower bound: 1.5× factor to account for commercial possibility. Upper bound: 4.5× factor to account for new technology application.
Stirring equipment2884Price quote for industrial farming equipment with a 1.5× factor for new equipment application.
Recollection equipment2267Price quote for industrial farming equipment with a 1.5× factor for new equipment application.
Total CAPEX [M$]$10,783$127,835 
CAPEX Annualized [M$ year−1]$794$16,053CRF of 7.4% used for lower bound and 12.5% used for upper bound.
CO2 capture from air [GtCO2 year−1]0.0640.18Only includes CO2 captured directly from the air.
Total CO2 capture [GtCO2 year−1]0.120.34Includes CO2 captured directly from the air and produced via calcination.
CAPEX [$ tCO2−1 captured]$12$89 
CAPEX [$ tCO2−1 produced]$7$47 
  1. aAssumed a scale-up factor68.