Description of Connecticut Air Pollution Control Regulation, Section 22a-174-42

Section 42 will address the potential air quality impacts of DG units through phased-in output-based standards for emissions of oxides of nitrogen, particulate matter, carbon monoxide and carbon dioxide; fuel sulfur content requirements to control emissions of sulfur dioxide; and measures to reduce the regulatory and administrative requirements for the owners and operators of DG units.

The requirements of Section 42 are developed to meet the following goals:

Emergency generator means a generator used only during emergencies or for maintenance and testing purposes with maximum annual operating hours that do not exceed 300 hours per calendar year. Emergency generators do not include generators operated in conjunction with any voluntary demand-reduction program or any other interruptible power supply arrangement witha utility, other market participant or system operator.

Emission Standards for Non-Emergency Generators

Phase NOx Attainment Area (lbs/MWh NOx Non-Attainment Area (lbs/MWh) CO (lbs/MWh) PM* (lbs/MWh) CO2 (lbs/MWh)
Phase I (Installed on or after January 1, 2004) 4 0.6 10 0.7 1,900
Phase II (Installed after January 1, 2008) 1.5 0.3 2 0.07 1,900
Phase III (Installed after January 1, 2012) 0.15 0.15 1 0.03 1,650

* Liquid fuel must meet on-road sulfur standards

* SO2 limit for waste/byproduct fuels

* Emergency generators must meet Federal non-road standards

Maximum Emissions Rates for CHP Systems Replacing Existing Thermal Systems

Pollutant Maximum Emission Rate (lbs/MMBtu)
Nitrogen Oxides 0.3
Particulate Matter N/A
Carbon Monoxide 0.08
Carbon Dioxide 117

Credit applied against standard based on displaced emissions:

  • For new plants, credit equivalent to new gas boiler.

  • For retrofit, actual displaced emissions up to a cap.