Comparison: CO2 reduction, Fischer-Tropsch, Boudouard.

 Comparison: CO2 reduction, Fischer-Tropsch, Boudouard. 

Author: David Judbadivski, systems engineering, principle inventor, retired, see CV in Linkedin.com. 

Note: They are used for artificial oil and/or gas domеstic production from air and water by extremly cheap solar and/or wind as energy source earlier invented and developed by me during many years, so

 to reach energy independency from hostile or impudent exporters, and to   decide now sore and insolvable problem to integrate huge solar and wind electricity in national grids, and distributed energy, if war time and terrorist attacts.

 Abstract. 

(a) CO2 reduction:  CO2 = CO - 283 KJ, CO2 = 1144 kwh * 0.004 / 0.4  USD/kwh = USD 11.44/ton CO2. CO = 11.44 * 44/ 28 = USD 17.9 + 283 * 4 /  3.6 / 28 = USD 11.1 and totally USD 29.0/ ton CO. If CO2 cycled, CO = USD 11.1 / ton.

CO + H2O = H2 + CO2 exhaust or in cycle - 3 KJ negligible. So H2 = 29.0 * 28 / 2 = USD 405 / ton, or if CO2 cycled, so 11.1 * 28 / 2 = USD 155.0 / ton. The CO costs must be devided on efficiency of  CO2 reduction + very expensive Capex. So realistic estimation can now be + 100% = USD 310 / ton H2 for CO2 cycled and 405 +155 = USD 560 / ton H2 for CO2 exhausted, plus expensive Capex.

(b) Boudouard reversible reaction: 

C + CO2 = 2CO - 173 KJ: 

CO = ( 12 * USD 120 ) / (2 * 28) =  USD 25 /ton + 173 * 4 / 3.6/ (2 * 28) =  USD 3.5/ton, and totally 25 + 3 5 = USD 28.5 /ton CO, can be processed with near 100% efficiency and low Capex by ordinary chemistry. So H2  = 28.5 * 28 / 2 = USD 405 / ton H2, if CO2 cycled, and USD 540/ ton H2, if CO2, if CO2 extracted from the air and then exhausted.

The said variant is carbon free or carbon neutral too, but partly consuming carbon-based fossil fuels, and can be named as  "half-green". 

(c) Fischer-Tropsch process adopted: 

C + 2 H20 = 2 H2 + CO2 - 179 KJ is fully based on carbon fossil fuels and CO2 pollution. 

H2 = 12 * 120 / 4 = USD 360/ton +  179 * 4 / 3.6 / 4 = USD 50/ton, and totally 360 + 50 = USD 410.0/ ton H2 + 20%. 

References.