# 98.113 Calculating GHG emissions.
You must calculate and report the annual process CO<sub>2</sub> emissions from each EAF not subject to paragraph (c) of this section using the procedures in either paragraph (a) or (b) of this section. For each EAF also subject to annual process CH<sub>4</sub> emissions reporting, you must also calculate and report the annual process CH<sub>4</sub> emissions from the EAF using the procedures in paragraph (d) of this section.
(a) Calculate and report under this subpart the process CO<sub>2</sub> emissions by operating and maintaining CEMS 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).
(b) Calculate and report under this subpart the annual process CO<sub>2</sub> emissions using the procedure in either paragraph (b)(1) or (b)(2) of this section.
(1) Calculate and report under this subpart the annual process CO<sub>2</sub> emissions from EAFs by operating and maintaining a CEMS according to the Tier 4 Calculation Methodology specified in § 98.33(a)(4) and the applicable requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources).
(2) Calculate and report under this subpart the annual process CO<sub>2</sub> emissions from the EAFs using the carbon mass balance procedure specified in paragraphs (b)(2)(i) and (b)(2)(ii) of this section.
(i) For each EAF, determine the annual mass of carbon in each carbon-containing input and output material for the EAF and estimate annual process CO<sub>2</sub> emissions from the EAF using Equation K-1 of this section. Carbon-containing input materials include carbon electrodes and carbonaceous reducing agents. If you document that a specific input or output material contributes less than 1 percent of the total carbon into or out of the process, you do not have to include the material in your calculation using Equation K-1 of this section.
Where:
E<sub>CO2</sub> = Annual process CO<sub>2</sub> emissions from an individual EAF (metric tons).
44/12 = Ratio of molecular weights, CO<sub>2</sub> to carbon.
2000/2205 = Conversion factor to convert tons to metric tons.
M<sub>reducing agent</sub>*i* = Annual mass of reducing agent *i* fed, charged, or otherwise introduced into the EAF (tons).
C<sub>reducing agent</sub>*i* = Carbon content in reducing agent *i* (percent by weight, expressed as a decimal fraction).
M<sub>electrode</sub>*m* = Annual mass of carbon electrode *m* consumed in the EAF (tons).
C<sub>electrode</sub>*m* = Carbon content of the carbon electrode *m* (percent by weight, expressed as a decimal fraction).
M<sub>ore</sub>*h* = Annual mass of ore *h* charged to the EAF (tons).
C<sub>ore</sub>*h* = Carbon content in ore *h* (percent by weight, expressed as a decimal fraction).
M<sub>flux</sub>*j* = Annual mass of flux material *j* fed, charged, or otherwise introduced into the EAF to facilitate slag formation (tons).
C<sub>flux</sub>*j* = Carbon content in flux material *j* (percent by weight, expressed as a decimal fraction).
M<sub>product</sub>*k* = Annual mass of alloy product *k* tapped from EAF (tons).
C<sub>product</sub>*k* = Carbon content in alloy product *k.* (percent by weight, expressed as a decimal fraction).
M<sub>non-product outgoing</sub>*l* = Annual mass of non-product outgoing material *l* removed from EAF (tons).
C<sub>non-product outgoing</sub>*l* = Carbon content in non-product outgoing material *l* (percent by weight, expressed as a decimal fraction).
(ii) Determine the combined annual process CO<sub>2</sub> emissions from the EAFs at your facility using Equation K-2 of this section.
Where:
CO<sub>2</sub> = Annual process CO<sub>2</sub> emissions from EAFs at facility used for the production of any ferroalloy listed in § 98.110 (metric tons).
E<sub>CO2</sub>*k* = Annual process CO<sub>2</sub> emissions calculated from EAF *k* calculated using Equation K-1 of this section (metric tons).
k = Total number of EAFs at facility used for the production of any ferroalloy listed in § 98.110.
(c) If GHG emissions from an EAF are vented through the same stack as any combustion unit or process equipment that reports CO<sub>2</sub> 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.
(d) For the EAFs at your facility used for the production of any ferroalloy listed in Table K-1 of this subpart, you must calculate and report the annual CH<sub>4</sub> emissions using the procedure specified in paragraphs (d)(1) and (2) of this section.
(1) For each EAF, determine the annual CH<sub>4</sub> emissions using Equation K-3 of this section.
Where:
E<sub>CH4</sub> = Annual process CH<sub>4</sub> emissions from an individual EAF (metric tons).
M<sub>product</sub>*i* = Annual mass of alloy product *i* produced in the EAF (tons).
2/2205 = Conversion factor to convert kg CH<sub>4</sub>/ton of product to metric tons CH<sub>4</sub>.
EF<sub>product</sub>*i* = CH<sub>4</sub> emission factor for alloy product *i* from Table K-1 in this subpart (kg of CH<sub>4</sub> emissions per metric ton of alloy product *i*).
(2) Determine the combined process CH<sub>4</sub> emissions from the EAFs at your facility using Equation K-4 of this section:
Where:
CH<sub>4</sub> = Annual process CH<sub>4</sub> emissions from EAFs at facility used for the production of ferroalloys listed in Table K-1 of this subpart (metric tons).
E<sub>CH4</sub>*j* = Annual process CH<sub>4</sub> emissions from EAF *j* calculated using Equation K-3 of this section (metric tons).
j = Total number of EAFs at facility used for the production of ferroalloys listed in Table K-1 of this subpart.
[74 FR 56374, Oct. 30, 2009, as amended at 75 FR 66461, Oct. 28, 2010; 78 FR 71954, Nov. 29, 2013]