SUBJECT: Proposed New BACT Guideline for DG in the South Coast Air Quality Management District

April 23, 2004

Proposed DG BACT Guidelines for Major Sources

BACT for major sources is based on federal Lowest Achievable Emission Rate (LAER) and is not required to pass a cost-effectiveness test. Therefore, the staff recommends that all new DG equipment at major sources be required henceforth to comply with the CARB 2007 standards as well. Major sources can use large combustion gas turbines with CHP, the smaller 1.5 MW Kawasaki gas turbine with CHP, equipment certified by CARB to meet the 2007 standards, or zero emission technology such as solar or wind power.

Proposed MSBACT Amendment

The proposed amendment to MSBACT for DG projects is shown in the table below. It is proposed that a new equipment category entitled "Distributed Generation" be created to encompass all DG projects greater than or equal to 1.5 MW, regardless of the DG technology that is chosen by the applicant. The guideline will require that the project meet the CARB 2007 standards for NOx, CO and VOC. AQMD's Clean Fuels Policy will be referenced as the guideline for SOx and PM. Ammonia emission guidelines for gas turbines and I.C. engines will be referenced as the guideline for inorganic emissions. This would constrain ammonia emissions in case an applicant chooses to meet the CARB 2007 NOx limit by using SCR technology. These changes would take effect on June 04, 2004 and are applicable to all sources except for those utilizing digester or landfill gas.

A staff white paper on these proposed BACT guidelines can be viewed by clicking here.



Proposed Distributed Generation Regulation

Rating/Size VOC NOx SOx CO PM-10 Inorganic
Greater than or equal to 1.5MW 0.02 lb/MW-hr1 0.07 lb/MW-hr1 See Clean Fules Policy in Part C of the BACT Guidelines 0.1 lb/MW-hr1 See Clean Fuels Policy in Part C of the BACT Guidelines See Appropriate Guideline for Gas Turbine or Stationary I.C. Engine


*Applies to any electricity generation project with one or more generation units having aggregate generation capacity greater than or equal to 1.5 MW producing electricity primarily for use within the facility in which it is sited and/or another facility(ies) with which it has a direct energy interconnection(s). Does not include distributed generation where the primary fuel is digester or landfill gas.

1 Calculation of lb/MW-hr may consider both electrical generation and waste heat utilization (3.413 MMBtu of waste heat is equivalent to 1 MW-hr)

Proposed I.C. Engine, Stationary Regulation

Rating/Size VOC NOx SOx CO PM-10 Inorganic
Non-Emergency Stationary I.C. Engine greater than or equal to 2064 bhp 25 ppmvd @ 15% O2 9 ppmvd @ 15% O2 See Clean Fules Policy in Part C of the BACT Guidelines 33 ppmvd @ 15% O2 (Old Regulation --05/08/98) 0.045 grams/bhp-hr (Old Regulation --05/08/98) Ammonia: 10 ppmvd @ 15% O2