Figure: 30 TAC §117.1215(d)(2)

Two equations for calculating the alternative system-wide emission specification in pounds per hour for each stationary gas turbine. The first equation calculates the nitrogen oxides in-stack concentration in parts per million by volume, and the second equation converts the in-stack concentration to the alternative system-wide emission specification in pounds per hour.

Where:

     Cinstack = the NOX in-stack concentration in parts per million by volume (ppmv);

     ANOX = the applicable NOX emission specification of §117.1205(f) or (g) of this title (relating
                  to Emission Specifications for Reasonably Available Control Technology (RACT)),
                  in ppmv NOX at 15% oxygen (O2), dry basis;

     %H2O =  the volume percent of water in the stack gases, as calculated from the
                    manufacturer’s data, or other data as approved by the executive director, at
                    megawatt (MW) rating and International Standards Organization (ISO) flow
                    conditions;

     %O2 =  the volume percent of O2 in the stack gases on a wet basis, as calculated from the
                  manufacturer’s data or other data as approved by the executive director, at MW
                  rating and ISO conditions;

     ELSW = system-wide emission specification in pounds per hour; and

     MF = the turbine manufacturer’s rated exhaust flow rate, in pounds per hour at MW rating
               and ISO flow conditions.