NR 440.50(1)
(1)
Applicability and designation of affected facility. NR 440.50(1)(a)(a) The provisions of this section are applicable to the following affected facilities: all stationary gas turbines with a heat input at peak load equal to or greater than 10.7 gigajoules (10 million Btu) per hour, based on the lower heating value of the fuel fired.
NR 440.50(1)(b)
(b) Any facility under
par. (a) which commences construction, modification, or reconstruction after October 3, 1977, is subject to the requirements of this section except as provided in
sub. (3) (e) and
(j).
NR 440.50(2)
(2) Definitions. As used in this section, terms not defined in this subsection have the meanings given in
s. NR 440.02.
NR 440.50(2)(a)
(a) “Base load" means the load level at which a gas turbine is normally operated.
NR 440.50(2)(b)
(b) “Combined cycle gas turbine" means any stationary gas turbine which recovers heat from the gas turbine exhaust gases to heat water or generate steam.
NR 440.50(2)(bg)
(bg) “Diffusion flame stationary combustion turbine" means any stationary combustion turbine where fuel and air are injected at the combustor and are mixed only by diffusion prior to ignition. A unit which is capable of operating in both lean premix and diffusion flame modes is considered a lean premix stationary combustion turbine when it is in the lean premix mode, and it is considered a diffusion flame stationary combustion turbine when it is in the diffusion flame mode.
NR 440.50(2)(br)
(br) “Duct burner" means a device that combusts fuel and that is placed in the exhaust duct from another source, such as a stationary gas turbine, internal combustion engine or kiln, to allow the firing of additional fuel to heat the exhaust gases before the exhaust gases enter a heat recovery steam generating unit.
NR 440.50(2)(c)
(c) “Efficiency" means the gas turbine manufacturer's rated heat rate at peak load in terms of heat input per unit of power output based on the lower heating value of the fuel.
NR 440.50(2)(d)
(d) “Electric utility stationary gas turbine" means any stationary gas turbine constructed for the purpose of supplying more than one-third of its potential electric output capacity to any utility power distribution system for sale.
NR 440.50(2)(e)
(e) “Emergency fuel" is a fuel fired by a gas turbine only during circumstances, such as natural gas supply curtailment or breakdown of delivery system, that make it impossible to fire natural gas in the gas turbine.
NR 440.50(2)(f)
(f) “Emergency gas turbine" means any stationary gas turbine which operates as a mechanical or electrical power source only when the primary power source for a facility has been rendered inoperable by an emergency situation.
NR 440.50(2)(fm)
(fm) “Excess emissions" means a specified averaging period over which one of the following occurs:
NR 440.50(2)(fm)2.
2. The total sulfur content of the fuel being combusted in the affected facility exceeds the limit specified in
sub. (4).
NR 440.50(2)(fm)3.
3. The recorded value of a particular monitored parameter is outside the acceptable range specified in the parameter monitoring plan for the affected unit.
NR 440.50(2)(g)
(g) “Fire-fighting turbine" means any stationary gas turbine that is used solely to pump water for extinguishing fires.
NR 440.50(2)(h)
(h) “Garrison facility" means any permanent military installation.
NR 440.50(2)(i)
(i) “Gas turbine model" means a group of gas turbines having the same nominal air flow, combustor inlet pressure, combustor inlet temperature, firing temperature, turbine inlet temperature and turbine inlet pressure.
NR 440.50(2)(j)
(j) “ISO standard day conditions" means 288
° Kelvin, 60% relative humidity and 101.3 kilopascals pressure.
NR 440.50(2)(k)
(k) “Ice fog" means an atmospheric suspension of highly reflective ice crystals.
NR 440.50(2)(km)
(km) “Lean premix stationary combustion turbine" means any stationary combustion turbine where the air and fuel are thoroughly mixed to form a lean mixture for combustion in the combustor. Mixing may occur before or in the combustion chamber. A unit which is capable of operating in both lean premix and diffusion flame modes is considered a lean premix stationary combustion turbine when it is in the lean premix mode, and it is considered a diffusion flame stationary combustion turbine when it is in the diffusion flame mode.
NR 440.50(2)(L)
(L) “Natural gas" means a naturally occurring fluid mixture of hydrocarbons, such as methane, ethane, or propane, produced in geological formations beneath the earth's surface that maintains a gaseous state at standard atmospheric temperature and pressure under ordinary conditions. Natural gas contains 20.0 grains or less of total sulfur per 100 standard cubic feet. Equivalents of this in other units are as follows: 0.068 weight percent total sulfur, 680 parts per million by weight (ppmw) total sulfur, and 338 parts per million by volume (ppmv) at 20 degrees Celsius total sulfur. Additionally, natural gas shall either be composed of at least 70% methane by volume or have a gross calorific value between 950 and 1100 Btu per standard cubic foot. Natural gas does not include the following gaseous fuels: landfill gas, digester gas, refinery gas, sour gas, blast furnace gas, coal-derived gas, producer gas, coke oven gas, or any gaseous fuel produced in a process which might result in highly variable sulfur content or heating value.
NR 440.50(2)(m)
(m) “Offshore platform gas turbines" means any stationary gas turbine located on a platform in an ocean.
NR 440.50(2)(n)
(n) “Peak load" means 100% of the manufacturer's design capacity of the gas turbine at ISO standard day conditions.
NR 440.50(2)(p)
(p) “Regenerative cycle gas turbine" means any stationary gas turbine that recovers heat from the gas turbine exhaust gases to preheat the inlet combustion air to the gas turbine.
NR 440.50(2)(q)
(q) “Simple cycle gas turbine" means any stationary gas turbine which does not recover heat from the gas turbine exhaust gases to preheat the inlet combustion air to the gas turbine, or which does not recover heat from the gas turbine exhaust gases to heat water or generate steam.
NR 440.50(2)(r)
(r) “Stationary gas turbine" means any simple cycle gas turbine, regenerative cycle gas turbine or any gas turbine portion of a combined cycle steam/electric generating system that is not self-propelled. It may, however, be mounted on a vehicle for portability.
NR 440.50(2)(s)
(s) “Turbines employed in oil or gas production or oil or gas transportation" means any stationary gas turbine used to provide power to extract crude oil or natural gas, or both, from the earth or to move crude oil or natural gas, or both, or products refined from these substances through pipelines.
NR 440.50(2)(t)
(t) “Unit operating day" means a 24-hour period between 12:00 midnight and the following midnight during which any fuel is combusted at any time in the unit. It is not necessary for fuel to be combusted continuously for the entire 24-hour period.
NR 440.50(2)(u)
(u) “Unit operating hour" means a clock hour during which any fuel is combusted in the affected unit. If the unit combusts fuel for the entire clock hour, it is considered to be a full unit operating hour. If the unit combusts fuel for only part of the clock hour, it is considered to be a partial unit operating hour.
NR 440.50(3)(a)(a) On and after the date on which the performance test required by
s. NR 440.08 is completed, every owner or operator subject to the provisions of this section, as specified in
pars. (b),
(c) and
(d), shall comply with one of the following, except as provided in
pars. (e) through
(L).
NR 440.50(3)(a)1.
1. No owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any stationary gas turbine, any gases which contain nitrogen oxides in excess of: -
See PDF for diagram 
where:
STD is the allowable ISO corrected, if required as given in sub. (6) (c), NOx emissions (percent by volume at 15% oxygen and on a dry basis)
Y is the manufacturer's rated heat rate at manufacturer's rated load (kilojoules per watt hour), or actual measured heat rate based on lower heating value of fuel as measured at actual peak load for the facility (the value of Y may not exceed 14.4 kilojoules per watt hour)
F is the NOx emission allowance for fuel-bound nitrogen as defined in subd. 4.
NR 440.50(3)(a)2.
2. No owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any stationary gas turbine, any gases which contain nitrogen oxides in excess of: -
See PDF for diagram
where:
STD is the allowable ISO corrected, if required as given in sub. (6) (c), NOx emissions (percent by volume at 15% oxygen and on a dry basis)
Y is the manufacturer's rated heat rate at manufacturer's rated peak load (kilojoules per watt hour), or actual measured heat rate based on lower heating value of fuel as measured at actual peak load for the facility (the value of Y may not exceed 14.4 kilojoules per watt hour)
F is the NOx emission allowance for fuel-bound nitrogen as defined in subd. 4.
NR 440.50(3)(a)3.
3. The use of F in
subds. 1. and
2. is optional. That is, the owner or operator may choose to apply an NO
x allowance for fuel-bound nitrogen and determine the appropriate F-value in accordance with
subd. 4. or may accept an F-value of zero.
NR 440.50(3)(a)4.
4. If the owner or operator elects to apply an NO
x emission allowance for fuel-bound nitrogen, F shall be defined according to the nitrogen content of the fuel during the most recent performance test required under
s. NR 440.08 as follows:
-
See PDF for table
where N is the nitrogen content of the fuel (percent by weight), or manufacturers may develop and submit to the department custom fuel-bound nitrogen allowances for each gas turbine model they manufacture. These fuel-bound nitrogen allowances shall be substantiated with data and must be approved for use by the administrator before the initial performance test required by
s. NR 440.08.
NR 440.50 Note
Note:
The administrator will publish notices of approval of custom fuel-bound nitrogen allowances in the federal register.
NR 440.50(3)(b)
(b) Electric utility stationary gas turbines with a heat input at peak load greater than 107.2 gigajoules per hour (100 million Btu/hour) based on the lower heating value of the fuel fired except as provided in
par. (d) shall comply with the provisions of
par. (a) 1.
NR 440.50(3)(c)
(c) Stationary gas turbines with a heat input at peak load equal to or greater than 10.7 gigajoules per hour (10 million Btu/hour) but less than or equal to 107.2 gigajoules per hour (100 million Btu/hour) based on the lower heating value of the fuel fired shall comply with the provisions of
par. (a) 2.
NR 440.50(3)(d)
(d) Electric utility stationary gas turbines with a manufacturer's rated base load at ISO conditions of 30 megawatts or less except as provided in
par. (b) shall comply with the provisions of
par. (a) 2.
NR 440.50(3)(e)
(e) Stationary gas turbines with a heat input at peak load equal to or greater than 10.7 gigajoules per hour (10 million Btu/hour) but less than or equal to 107.2 gigajoules per hour (100 million Btu/hour) based on the lower heating value of the fuel fired and that have commenced construction prior to October 3, 1982 are exempt from
par. (a).
NR 440.50(3)(f)
(f) Stationary gas turbines using water or steam injection for control of NO
x emissions are exempt from
par. (a) when ice fog is deemed a traffic hazard by the owner or operator of the gas turbine.
NR 440.50(3)(g)
(g) Emergency gas turbines, military gas turbines for use in other than a garrison facility, military gas turbines installed for use as military training facilities and fire fighting gas turbines are exempt from
par. (a).
NR 440.50(3)(h)
(h) Stationary gas turbines engaged by manufacturers in research and development of equipment for both gas turbine emission control techniques and gas turbine efficiency improvements may be exempted from
par. (a) on a case-by-case basis by the department.
NR 440.50(3)(i)
(i) Exemptions from the requirements of
par. (a) may be granted on a case-by-case basis as determined by the department in specific geographical areas where mandatory water restrictions are required by governmental agencies because of drought conditions. These exemptions may be allowed only while the mandatory water restrictions are in effect.
NR 440.50(3)(j)
(j) Stationary gas turbines with a heat input at peak load greater than 107.2 gigajoules per hour that commenced construction, modification or reconstruction between the dates of October 3, 1977, and January 27, 1982, and were required in the September 10, 1979 federal register (44 FR 52792) to comply with
40 CFR 60.332 (a) (1), except electric utility stationary gas turbines, are exempt from
par. (a).
NR 440.50(3)(k)
(k) Stationary gas turbines with a heat input greater than or equal to 10.7 gigajoules per hour (10 million Btu/hour) when fired with natural gas are exempt from
par. (a) 2. when being fired with an emergency fuel.
NR 440.50(3)(L)
(L) Regenerative cycle gas turbines with a heat input less than or equal to 107.2 gigajoules per hour (100 million Btu/hour) are exempt from
par. (a).
NR 440.50(4)
(4) Standard for sulfur dioxide. On and after the date on which the performance test required to be conducted by
s. NR 440.08 is completed, every owner or operator subject to the provisions of this section shall comply with one or the other of the following conditions:
NR 440.50(4)(a)
(a) No owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any stationary gas turbine any gases which contain sulfur dioxide in excess of 0.015% by volume at 15% oxygen and on a dry basis.
NR 440.50(4)(b)
(b) No owner or operator subject to the provisions of this section may burn in any stationary gas turbine any fuel which contains sulfur in excess of 0.8% by weight (8000 ppmw).
NR 440.50(5)(a)(a) Except as provided in
par. (b), the owner or operator of any stationary gas turbine subject to the provisions of this section and using water or steam injection to control NO
x emissions shall install, calibrate, maintain and operate a continuous monitoring system to monitor and record the fuel consumption and ratio of water or steam to fuel being fired in the turbine.
NR 440.50(5)(b)
(b) The owner or operator of any stationary gas turbine that commenced construction, reconstruction or modification after October 3, 1977, but before July 8, 2004, and which uses water or steam injection to control NO
x emissions may, as an alternative to operating the continuous monitoring system described in
par. (a), install, certify, maintain, operate and quality-assure a continuous emission monitoring system (CEMS) consisting of NO
x and O
2 monitors. As an alternative, a CO
2 monitor may be used to adjust the measured NO
x concentrations to 15% O
2 by either converting the CO
2 hourly averages to equivalent O
2 concentrations using Equation F-14a or F-14b in Appendix F of
40 CFR part 75, incorporated by reference in
s. NR 440.17 (1), and making the adjustments to 15% O
2, or by using the CO
2 readings directly to make the adjustments, as described in Method 20. If the option to use a CEMS is chosen, the CEMS shall be installed, certified, maintained and operated as follows:
NR 440.50(5)(b)1.
1. Each CEMS shall be installed and certified according to PS 2 and 3 (for diluent) of
40 CFR part 60, Appendix B, incorporated by reference in
s. NR 440.17 (1), except the 7-day calibration drift is based on unit operating days, not calendar days. Appendix F, Procedure 1 is not required. The relative accuracy test audit (RATA) of the NO
x and diluent monitors may be performed individually or on a combined basis, that is, the relative accuracy tests of the CEMS may be performed in one of the following ways:
NR 440.50(5)(b)1.c.
c. On a ppm basis (for NO
x) and a percent CO
2 basis, for a CO
2 monitor that uses the procedures in Method 20 to correct the NO
x data to 15% O
2.
NR 440.50(5)(b)2.
2. As specified in
s. NR 440.13 (5) (b), during each full unit operating hour, each monitor shall complete a minimum of one cycle of operation (sampling, analyzing and data recording) for each 15-minute quadrant of the hour, to validate the hour. For partial unit operating hours, at least one valid data point shall be obtained for each quadrant of the hour in which the unit operates. For unit operating hours in which required quality assurance and maintenance activities are performed on the CEMS, a minimum of 2 valid data points, one in each of 2 quadrants, are required to validate the hour.
NR 440.50(5)(b)3.a.
a. For each unit operating hour in which a valid hourly average, as described in
subd. 2., is obtained for both NO
x and diluent, the data acquisition and handling system shall calculate and record the hourly NO
x emissions in the units of the applicable NO
x emission standard under
sub. (3) (a), that is, percent NO
x by volume, dry basis, corrected to 15% O
2 and International Organization for Standardization (ISO) standard conditions, if required as given in
sub. (6) (c) 1. For any hour in which the hourly average O
2 concentration exceeds 19.0% O
2, a diluent cap value of 19.0% O
2 may be used in the emission calculations.
NR 440.50(5)(b)3.b.
b. A worst case ISO correction factor may be calculated and applied using historical ambient data. For the purpose of this calculation, substitute the maximum humidity of ambient air (H
o), minimum ambient temperature (T
a), and minimum combustor inlet absolute pressure (P
o) into the ISO correction equation.
NR 440.50(5)(b)3.c.
c. If the owner or operator has installed a NO
x CEMS to meet the requirements of
40 CFR part 75, and is continuing to meet the ongoing requirements of
40 CFR part 75, the CEMS may be used to meet the requirements of this section, except that the missing data substitution methodology provided for at
40 CFR part 75, subpart D, is not required for purposes of identifying excess emissions. Instead, periods of missing CEMS data are to be reported as monitor downtime in the excess emissions and monitoring performance report required in
s. NR 440.07 (3).
NR 440.50(5)(c)
(c) For any turbine that commenced construction, reconstruction or modification after October 3, 1977, but before July 8, 2004, and which does not use steam or water injection to control NO
x emissions, the owner or operator may, for purposes of determining excess emissions, use a CEMS that meets the requirements of
par. (b). Also, if the owner or operator has previously submitted and received EPA, department or local permitting authority approval of a petition for an alternative procedure of continuously monitoring compliance with the applicable NO
x emission limit under
sub. (3), that approved procedure may continue to be used.
NR 440.50(5)(d)
(d) The owner or operator of any new turbine constructed after July 8, 2004, and which uses water or steam injection to control NO
x emissions may elect to use either the requirements in
par. (a) for continuous water or steam to fuel ratio monitoring or may use a NO
x CEMS installed, certified, operated, maintained and quality-assured as described in
par. (b).
NR 440.50(5)(e)
(e) The owner or operator of any new turbine that commences construction after July 8, 2004, and which does not use water or steam injection to control NO
x emissions may elect to use a NO
x CEMS installed, certified, operated, maintained and quality-assured as described in
par. (b). Other acceptable monitoring approaches include periodic testing approved by EPA, the department or local permitting authority or continuous parameter monitoring as described in
par. (f).
NR 440.50(5)(f)
(f) The owner or operator of a new turbine that commences construction after July 8, 2004, which does not use water or steam injection to control NO
x emissions may perform continuous parameter monitoring as follows:
NR 440.50(5)(f)1.
1. For a diffusion flame turbine without add-on selective catalytic reduction controls (SCR), the owner or operator shall define at least 4 parameters indicative of the unit's NO
x formation characteristics and shall monitor these parameters continuously.
NR 440.50(5)(f)2.
2. For any lean premix stationary combustion turbine, the owner or operator shall continuously monitor the appropriate parameters to determine whether the unit is operating in low-NO
x mode.
NR 440.50(5)(f)3.
3. For any turbine that uses SCR to reduce NO
x emissions, the owner or operator shall continuously monitor appropriate parameters to verify the proper operation of the emission controls.
NR 440.50(5)(f)4.
4. For affected units that are also regulated under
40 CFR part 75, if the owner or operator elects to monitor the NO
x emission rate using the methodology in Appendix
E of
40 CFR part 75, incorporated by reference in
s. NR 440.17 (1), or the low mass emissions methodology in
40 CFR 75.19, the requirements of this paragraph may be met by performing the parametric monitoring described in section 2.3 of Appendix
E of
40 CFR part 75 or in
40 CFR 75.19 (c) (1) (iv) (H).
NR 440.50(5)(g)
(g) The steam or water to fuel ratio or other parameters that are continuously monitored as described in
par. (a),
(d) or
(f) shall be monitored during the performance test required under
s. NR 440.08, to establish acceptable values and ranges. The owner or operator may supplement the performance test data with engineering analyses, design specifications, manufacturer's recommendations and other relevant information to define the acceptable parametric ranges more precisely. The owner or operator shall develop and keep on-site a parameter monitoring plan which explains the procedures used to document proper operation of the NO
x emission controls. The plan shall include the parameters monitored and the acceptable ranges of the parameters as well as the basis for designating the parameters and acceptable ranges. Any supplemental data such as engineering analyses, design specifications, manufacturer's recommendations and other relevant information shall be included in the monitoring plan. For affected units that are also subject to
40 CFR part 75 and that use the low mass emissions methodology in
40 CFR 75.19 or the NO
x emission measurement methodology in Appendix
E of
40 CFR part 75, the owner or operator may meet the requirements of this paragraph by developing and keeping on-site (or at a central location for unmanned facilities) a quality-assurance plan, as described in
40 CFR 75.19 (e) (5) or in section 2.3 of Appendix
E and section 1.3.6 of Appendix
B of
40 CFR part 75, both incorporated by reference in
s. NR 440.17 (1).
NR 440.50(5)(h)
(h) The owner or operator of any stationary gas turbine subject to the provisions of this section:
NR 440.50(5)(h)1.
1. Shall monitor the total sulfur content of the fuel being fired in the turbine, except as provided in
subd. 3. The sulfur content of the fuel shall be determined using total sulfur methods described in
sub. (6) (d). Alternatively, if the total sulfur content of the gaseous fuel during the most recent performance test was less than 0.4 weight percent (4000 ppmw), ASTM D4084-94, D5504-01, D6228-98, or Gas Processors Association Standard 2377-86, incorporated by reference in
s. NR 440.17 (2) (a) 52., 64. and 68. and (m). respectively, which measure the major sulfur compounds may be used.
NR 440.50(5)(h)2.
2. Shall monitor the nitrogen content of the fuel combusted in the turbine, if the owner or operator claims an allowance for fuel bound nitrogen, that is, if an F-value greater than zero is being or will be used by the owner or operator to calculate STD in
sub. (3). The nitrogen content of the fuel shall be determined using methods described in
sub. (6) (c) 9. or an approved alternative.
NR 440.50(5)(h)3.
3. Notwithstanding the provisions of
subd. 1., the owner or operator may elect not to monitor the total sulfur content of the gaseous fuel combusted in the turbine, if the gaseous fuel is demonstrated to meet the definition of natural gas in
sub. (2) (L), regardless of whether an existing custom schedule approved by the department for this section requires the monitoring. The owner or operator shall use one of the following sources of information to make the required demonstration:
NR 440.50(5)(h)3.a.
a. The gas quality characteristics in a current, valid purchase contract, tariff sheet or transportation contract for the gaseous fuel, specifying that the maximum total sulfur content of the fuel is 20.0 grains/100 scf or less.
NR 440.50(5)(h)3.b.
b. Representative fuel sampling data which show that the sulfur content of the gaseous fuel does not exceed 20 grains/100 scf. At a minimum, the amount of fuel sampling data specified in section 2.3.1.4 or 2.3.2.4 of Appendix D to
40 CFR part 75, incorporated by reference in
s. NR 440.17 (1), is required.
NR 440.50(5)(h)4.
4. For any turbine that commenced construction, reconstruction or modification after October 3, 1977, but before July 8, 2004, and for which a custom fuel monitoring schedule has previously been approved, the owner or operator may, without submitting a special petition to the department, continue monitoring on this schedule.
