1. (1) Owners and operators must meet the following facility-level daily weighted average emission limits on a pounds of NO_x per megawatt hour (lb/MWh) basis for all applicable SCCTs, electric storage resources and/or renewable generation resources at a facility.

   1. (i) By May 1, 2023:

      	Emission Limit (lb NOx/MWh)
      All SCCTs	3.0

   2. (ii) By May 1, 2025:

      Fuel Type	Effective Daily Emission Limit (lb NOx/MWh)
      Gaseous fuels	1.5
      Distillate oil or other liquid fuel	2.0

2. (2) The owner or operator of an SCCT that uses electric storage or renewable energy resources to inject electricity to the transmission and distribution system may demonstrate compliance with the applicable effective daily NO_x emission limits by including the electrical energy, in MWh, injected to the transmission and distribution system from electric storage and/or renewable generation resources in the emission rate calculation provided that:

   1. (i) the renewable generation resource and/or the electric storage resource must be directly connected to the same physical substation as the SCCT with which it is being averaged; or
   2. (ii) within one-half mile radius of the SCCT with which it is being averaged;
   3. (iii) all sources that are averaged under this compliance option must be under common control.

3. (3) The effective emission rate may be calculated by:

   1. (i) Effective Rate = ​

      1. (a) MassNO_x = NO_x emissions (pounds) each day from all applicable SCCTs at the permitted facility.
      2. (b) MWh_CT = electrical energy delivered to the transmission and distribution system (in MWh) from applicable SCCTs at the permitted facility each day.
      3. (c) MWh_ST = electrical energy delivered to the transmission and distribution system (in MWh) from storage resources over each day.
      4. (d) MWh_RE = electrical energy delivered to the transmission and distribution system (in MWh) from renewable generation each day.

      ​

4. (4) If the owner or operator burns both gaseous fuel and liquid fuel during the same day, a facility electrical energy (MWh) weighted average must be calculated to determine a resultant mix fuel emission rate. The mix fuel rate must first be calculated to determine the allowable emission rate and then calculated again to determine the actual mix fuel emission rate.

   1. (i) Allowable Mix Fuel Rate = ^{RateGxGenG+Rate0xGen0}/_GenG+Gen0 where:

      1. (a) RateG = Effective daily emission limit (lb NO_x/MWh) burning gas as defined in subdivision (b) of this section.
      2. (b) RateO = Effective daily emission limit (lb NO_x/MWh) burning oil as defined in subdivision (b) of this section.
      3. (c) GenG = electrical energy (MWh) generated burning gas each day.
      4. (d) GenO = electrical energy (MWh) generated burning oil each day.

   2. (ii) Actual Mix Fuel Rate = ^{RateGxGenG+Rate0xGen0}/_{GenG+Gen0+GenR+GenS} where:

      1. (a) RateG = lb NO_x/MWh burning gas.
      2. (b) RateO = lb NO_x/MWh burning oil.
      3. (c) GenG = electrical energy (MWh) generated burning gas each day.
      4. (d) GenO = electrical energy (MWh) generated burning oil each day.
      5. (e) GenR = electrical energy (MWh) injected to the transmission and distribution system from renewable energy resources each day.
      6. (f) GenS = electrical energy (MWh) injected to the transmission and distribution system from electric storage resources each day.

(a) Ozone season stop.

An owner or operator of an existing SCCT may opt to comply with this Subpart by not operating the SCCT during the ozone season. The ozone season stop provision must be included as an enforceable permit condition in a final permit or permit modification issued prior to the applicable compliance deadline of this Subpart.

(b) Electric storage and renewable energy resources.

An owner or operator of an SCCT may opt to comply with this Subpart by meeting the following weighted average output-based emission limits on a daily basis pursuant to the following: