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Reciprocating Internal Combustion Engines (RICE)

What Are Reciprocating Internal Combustion Engines or RICE?

RICE use pistons that alternatively move back and forth to convert pressure into rotating motion. They're commonly used at power and manufacturing plants to generate electricity and to power pumps and compressors. RICE are also used in emergencies to produce electricity and pump water for flood and fire control. The U.S. Environmental Protection Agency (EPA) has recently finalized new air quality regulations that place requirements on owners and operators of a wide variety of stationary RICE.

Why Does EPA Regulate RICE?

RICE are common combustion sources that collectively can have a significant impact on air quality and public health. The air toxics emitted from stationary engines include formaldehyde, acrolein, acetaldehyde and methanol. Exposure to these air toxics may produce a wide variety of health difficulties for people including irritation of the eyes, skin and mucous membranes, and central nervous system problems. RICE engines also emit the conventional air pollutants created when fuel is burned including carbon monoxide (CO), nitrogen oxides (NOx), volatile organic compounds (VOCs), and particulate matter (PM). The health effects of these pollutants include a range of respiratory (breathing) issues, especially asthma among children and seniors.

How Does EPA Regulate Stationary Engines?

EPA air quality requirements for stationary engines differ according to:

• whether the engine is new or existing, and
• whether the engine is located at an area source or major source and whether the engine is a compression ignition or a spark ignition engine. "Spark ignition" engines are further subdivided by power cycle - -i.e., two vs. four stroke, and whether the engine is "rich burn" (burning with a higher amount of fuel as compared to air) or "lean burn" (less fuel compared to air) engine.

Several regulations have expanded the number and type of stationary RICE that must comply with federal requirements. These include:

• National Emission Standard for Hazardous Air Pollutants (NESHAP) for Reciprocating Internal Combustion Engines (RICE) – 40 Code of Federal Regulations Part 63, Subpart ZZZZ ("the RICE rule")
• New Source Performance Standards (NSPS) - Standards of Performance for Stationary Spark Ignition Internal Combustion Engines (40 CFR Part 60 Subpart JJJJ - Scroll to reach the Subpart.) – "the Spark Ignition NSPS rule"
• Standards of Performance for Stationary Compression Ignition Internal Combustion Engines (40 CFR Part 60 Subpart IIII - Scroll to reach the Subpart.) – "the Compression Ignition NSPS rule"

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RICE Rule Applicability

The RICE rule Does Not Apply to:

1. Motor vehicles, or to non-road engines, which are:
   • self-propelled (tractors, bulldozers)
   • propelled while performing their function (lawnmowers)
   • portable or transportable (has wheels, skids, carrying handles, dolly, trailer or platform). Note: a portable non-road engine becomes stationary if it stays in one location for more than 12 months (or full annual operating period of a seasonal source)
2. Existing emergency engines located at residential, institutional, or commercial area sources, used or obligated to be available ≤15 hr/yr for emergency demand response, and not used for local reliability. Engine must meet Subpart ZZZZ emergency engine operational requirements:
   • Unlimited use for emergencies (e.g., power outage, fire, flood)
   • Emergency engines may operate for 100 hr/yr for any combination of the following:
     1. maintenance/testing;
     2. emergency demand response (in situations when a blackout is imminent – either the reliability coordinator has declared an Energy Emergency Alert Level 2 as defined in the North American Reliability Corporation (NERC) Reliability Standard; or there is a deviation of voltage or frequency of 5 percent or greater below standard voltage or frequency);
     3. 50 hr/yr of the 100 hr/yr allocation can be used for:
        1. non-emergency situations if no financial arrangement
        2. local reliability as part of a financial arrangement with another entity if specific criteria met (existing RICE at area sources of HAP only)
        3. peak shaving until May 3, 2014 (existing RICE at area sources of HAP only) if part of a peak shaving (load management) program with the local distribution system operator and the power is provided only to the facility or to support the local distribution system

The RICE rule Applies to:

1. Engines >500 Horsepower (HP) at major source of HAP:
   Existing engines if constructed before December 19, 2002
   New engines if constructed on or after December 19, 2002
   Reconstructed engines if reconstruction began on or after December 19, 2002
2. Engines ≤500 HP located at major source of HAP and engines of all horsepower located at an area source of HAP:
   Existing engines if constructed before June 12, 2006
   New engines if constructed on or after June 12, 2006
   Reconstructed engines if reconstruction began on or after June 12, 2006

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Determining RICE Rule Compliance Requirements

RICE Rule requirements are complex – but they are similar for several groups of engines, as summarized in the tables below.

Engine Subcategory	Compliance Requirements
Existing non-emergency: CI ≥100 HP at major source CI >300 HP at area source SI 100-500 HP at major source	Initial emission performance test Subsequent performance testing every 8,760 hours of operation or 3 years for engines >500 HP (5 years if limited use) Operating limitations - catalyst pressure drop and inlet temperature for engines >500 HP Notifications Semiannual compliance reports (annual if limited use) Existing non-emergency CI >300 HP: Ultra low sulfur diesel (ULSD) Crankcase emission control requirements
Existing non-emergency SI 4SLB/4SRB >500 HP at area source used >24 hours/year and not in remote area	Initial and annual catalyst activity checks High temperature engine shutdown or continuously monitor catalyst inlet temperature Notifications Semiannual compliance reports
Engine Subcategory	Compliance Requirements
Existing emergency/black start: <100 HP at major source ≤500 HP at major source All at area source Existing non-emergency: <100 HP at major source CI ≤300 HP at area source SI ≤500 HP at area source SI 2SLB >500 HP at area source SI LFG/DG >500 HP at area source SI 4SLB/4SRB >500 HP at area source used ≤24 hours/year or in remote area	Operate/maintain engine & control device per manufacturer’s instructions or owner-developed maintenance plan May use oil analysis program instead of prescribed oil change frequency Emergency engines must have hour meter and record hours of operation Keep records of maintenance Notifications not required Reporting and ULSD for emergency engines used for emergency demand response or local reliability
Engine Subcategory	Compliance Requirements
Existing non-emergency: SI 4SRB >500 HP at major source New non-emergency: SI 2SLB >500 HP at major source SI 4SLB >250 HP at major source SI 4SRB >500 HP at major source CI >500 HP at major source	Initial emission performance test Subsequent performance testing semiannually (can reduce frequency to annual) (subsequent performance testing required for 4SRB engine complying with formaldehyde % reduction standard if engine is ≥5000 HP) Operating limitations - catalyst pressure drop and inlet temperature Notifications Semiannual compliance reports
Engine Subcategory	Compliance Requirements
New emergency/limited use >500 HP at major source	Initial notification Reporting and ULSD for emergency engines used for emergency demand response or local reliability
New non-emergency LFG/DG >500 HP at major source	Initial notification Monitor/record fuel usage daily Annual report of fuel usage

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Emission Standards: Existing RICE at Major Sources

HP	Engine Subcategory
	Non-emergency					Emergency
	CI	SI 2SLB	SI 4SLB	SI 4SRB	SI LFG/DG
<100	Change oil and filter and inspect cleaner (CI) or spark plugs (SI) every 1,000 hours of operation or annually; inspect hoses and belts every 500 hours of operation or annually					Change oil/filter & inspect hoses/belts every 500 hours or annually; inspect air cleaner (CI) or spark plugs (SI) every 1,000 hours or annually
100-300	230 ppm CO	225 ppm CO	47 ppm CO	10.3 ppm CH2O	177 ppm CO
300-500	49 ppm CO or 70% CO reduction
>500	23 ppm CO or 70% CO reduction	No standards	No standards	350 ppb CH2O or 76% CH2O reduction	No standards	No standards
Note: Existing limited use engines >500 HP at major sources do not meet any emission standards. Existing black start engines ≤500 HP at major sources must meet work practice standards.

Emission Standards: Existing RICE Located at Area Sources

HP	Engine Subcategory
	Non-emergency					Emergency or Black Start
	CI	SI 2SLB	SI 4S in remote areas	SI 4S not in remote areas	SI LFG/DG
≤300	Change oil/filter & inspect air cleaner every 1,000 hours or annually; inspect hoses/belts every 500 hours or annually	Change oil/filter, inspect spark plugs, & inspect hoses/belts every 4,320 hours or annually	Change oil/filter, inspect spark plugs, & inspect hoses/belts every 1,440 hours of operation or annually	Change oil/filter, inspect spark plugs, & inspect hoses/belts every 1,440 hours of operation or annually	Change oil/filter, inspect spark plugs, & inspect hoses/belts every 1,440 hours of operation or annually	Change oil/filter & inspect hoses/belts every 500 hours or annually; inspect air cleaner (CI) or spark plugs (SI) every 1,000 hours or annually
300-500	49 ppm CO or 70% CO reduction*
>500	23 ppm CO or 70% CO reduction		Change oil/filter, inspect spark plugs, & inspect hoses/belts every 2,160 hours of operation or annually	if engine used >24 hrs/yr: 4SLB: Install oxidation catalyst 4SRB: Install NSCR

Emission Standards: New RICE Located at Major Sources

HP	Engine Subcategory
	Non-emergency					Emergency
	CI	SI 2SLB	SI 4SLB	SI 4SRB	SI LFG/DG
<250	Comply with CI NSPS	Comply with SI NSPS	Comply with SI NSPS	Comply with SI NSPS	Comply with SI NSPS	Comply with CI/SI NSPS
250-500			14 ppm CH2O or 93% CO reduction
>500	580 ppb CH2O or 70% CO reduction	12 ppm CH2O or 58% CO reduction		350 ppb CH2O or 76% CH2O reduction	No standards	No standards
Note: New limited use engines >500 HP at major sources do not meet any emission standards under the NESHAP.

New RICE Located at Area Sources: meet Stationary Engine NSPS CI: part 60 subpart IIII SI: part 60 subpart JJJ

 

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Determining RICE New Source Performance Standards (NSPS) Compliance Requirements

The NSPS rules include two alternative compliance approaches:

1. Operators comply by purchasing an engine certified by the manufacturer. 
2. Operators comply by meeting emission limits for an engine not certified by the manufacturer.

If you own or operate a Compression Ignition engine you are subject to the NSPS at 40 CFR 60, Subpart IIII if the engine was:

• Constructed (ordered) after July 11, 2005, and manufactured after April 1, 2006 (July 1, 2006 for fire pump engines), or
• Modified or reconstructed after July 11, 2005.
• Except for engines > 30 liters per cylinder (l/cyl) displacement, performance testing is not required - you achieve compliance by:
  • purchasing a new engine that has been certified by EPA, and
  • installing, configuring, operating, and maintaining the engine per the manufacturer’s instructions.

If you own or operate a Spark Ignition engine you are subject to the NSPS at 40 CFR 60, Subpart JJJJ if the engine was:

• Constructed (ordered) after 6/12/2006 and the engine is
  • >500 HP manufactured on/after 7/1/2007 (except lean burn 500≤HP<1,350)
  • lean burn 500≤HP<1,350 manufactured on/after 1/1/2008
  • <500 HP manufactured on/after 7/1/2008
  • emergency >25 HP manufactured on/after 1/1/2009
  • modified/reconstructed after 6/12/2006.
• For certain Spark Ignition engines manufactured on/after July 1, 2008, the engine manufacturer is required to certify that the engine meets emission limits. As the owner or operator of the engine you can comply by purchasing a certified engine, and operating it according to manufacturer’s instructions. These SI engine types include:
  • ≤ 25 HP,
  • gasoline engines >25 HP, and
  • rich burn LPG engines >25 HP.
• For other Spark Ignition engines, EPA made it optional for the manufacturer to certify that their engines meet the applicable emission limits. Owners or operators can comply either by purchasing an engine that the manufacturer has voluntarily certified, or by conducting performance testing to demonstrate that the engine meets the applicable emission limits.

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