98.163—Calculating GHG emissions.
You must calculate and report the annual CO2 emissions from each hydrogen production process unit using the procedures specified in either paragraph (a) or (b) of this section.
(a) Continuous Emissions Monitoring Systems (CEMS).
Calculate and report under this subpart the CO2 emissions by operating and maintaining CEMS according to the Tier 4 Calculation Methodology specified in § 98.33(a)(4) and all associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources).
(b) Fuel and feedstock material balance approach.
Calculate and report CO2 emissions as the sum of the annual emissions associated with each fuel and feedstock used for hydrogen production by following paragraphs (b)(1) through (b)(3) of this section.
(1) Gaseous fuel and feedstock.
You must calculate the annual CO2 emissions from each gaseous fuel and feedstock according to Equation P-1 of this section:
Where:
CO2 = Annual CO2 process emissions arising from fuel and feedstock consumption (metric tons/yr).
Fdstkn = Volume of the gaseous fuel and feedstock used in month n (scf (at standard conditions of 68 °F and atmospheric pressure) of fuel and feedstock).
CCn = Average carbon content of the gaseous fuel and feedstock, from the results of one or more analyses for month n (kg carbon per kg of fuel and feedstock). If measurements are taken more frequently than monthly, use the arithmetic average of measurement values within the month to calculate a monthly average.
MWn = Average molecular weight of the gaseous fuel and feedstock from the results of one or more analyses for month n (kg/kg-mole).
MVC = Molar volume conversion factor (849.5 scf per kg-mole at standard conditions).
k = Months in the year.
44/12 = Ratio of molecular weights, CO2 to carbon. 0.001 = Conversion factor from kg to metric tons.
(2) Liquid fuel and feedstock.
You must calculate the annual CO2 emissions from each liquid fuel and feedstock according to Equation P-2 of this section:
Where:
CO2 = Annual CO2 emissions arising from fuel and feedstock consumption (metric tons/yr).
Fdstkn = Volume of the liquid fuel and feedstock used in month n (gallons of fuel and feedstock).
CCn = Average carbon content of the liquid fuel and feedstock, from the results of one or more analyses for month n (kg carbon per gallon of fuel and feedstock).
k = Months in the year.
44/12 = Ratio of molecular weights, CO2 to carbon.
0.001 = Conversion factor from kg to metric tons.
(3) Solid fuel and feedstock.
You must calculate the annual CO2 emissions from each solid fuel and feedstock according to Equation P-3 of this section:
Where:
CO2 = Annual CO2 emissions from fuel and feedstock consumption in metric tons per month (metric tons/yr).
Fdstkn = Mass of solid fuel and feedstock used in month n (kg of fuel and feedstock).
CCn = Average carbon content of the solid fuel and feedstock, from the results of one or more analyses for month n (kg carbon per kg of fuel and feedstock).
k = Months in the year.
44/12 = Ratio of molecular weights, CO2 to carbon.
0.001 = Conversion factor from kg to metric tons.
(c)
If GHG emissions from a hydrogen production process unit are vented through the same stack as any combustion unit or process equipment that reports CO2 emissions using a CEMS that complies with the Tier 4 Calculation Methodology in subpart C of this part (General Stationary Fuel Combustion Sources), then the calculation methodology in paragraph (b) of this section shall not be used to calculate process emissions. The owner or operator shall report under this subpart the combined stack emissions according to the Tier 4 Calculation Methodology in § 98.33(a)(4) and all associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources).