Diesel fuel generator - Hours of operation

Download the diesel fuel generator operating hours calculator to help you estimate releases of National Pollutant Release Inventory (NPRI) substances.

Diesel-powered reciprocating engine generators (up to 600 horsepower) release Part 1, 2, 4 and 5 Substances. This release calculator uses default emission factors and can be adapted to use site-specific emission factors. If you want to use a site-specific emission factor, enter it in the emission factor column, but be sure to convert the units correctly. 

The spreadsheet calculators use emission factors based on uncontrolled emission sources. If you use an emission control device and the default emission factor is uncontrolled, use this formula to adjust the spreadsheet calculation:

Controlled emissions = uncontrolled emission x ((100 - control efficiency)/100)

Since NPRI reporting thresholds are for the facility as a whole, you may need to combine the air releases you calculate with releases from other sources at your facility.

The following sections explain how the spreadsheet calculator works.

Suggested estimation methodology: emission factor

The equation for estimation using an emission factor is:

E = A x EF

where:

• E = emissions
• A = activity rate
• EF = emission factor

Input data

B = hours of operation [hours]
C = operating horsepower [hp]

Calculate the activity rate by the following formula:

A = B x C

Use the emission factors in the tables below to calculate the emissions for each substance.

Substance releases

Part 1 releases

Substance	Chemical Abstracts Service registry number (CAS RN)1	Part	Emission factor (EF)2	EF units
Acetaldehyde	75-07-0	1A	2.435E-06	kg/hp - hour
Acrolein	107-08-8	1A	1.469E-07	kg/hp - hour
Benzene	71-43-2	1A	2.962E-06	kg/hp - hour
1,3-butadiene	106-99-0	1A	6.207E-08	kg/hp - hour
Formaldehyde	50-00-0	1A	3.747E-06	kg/hp - hour
Naphthalene	91-20-3	1A	2.693E-07	kg/hp - hour
Propylene	115-07-1	1A	8.192E-06	kg/hp - hour
Toluene	108-88-3	1A	1.299E-06	kg/hp - hour
Xylene (all isomers)	1330-20-7	1A	9.049E-07	kg/hp - hour
Mercury (and its compounds)	Footnote *	1B	9.570E-10	kg/hp - hour

Part 2 releases

Substance	Chemical Abstracts Service registry number (CAS RN)1	Emission factor (EF)2	EF units
Acenaphthene	83-32-9	2.254E-09	kg/hp - hour
Acenaphthylene	208-96-8	8.033E-09	kg/hp - hour
Anthracene	120-12-7	5.938E-09	kg/hp - hour
Benzo[a]anthracene	56-55-3	5.334E-09	kg/hp - hour
Chrysene	218-01-9	1.121E-09	kg/hp - hour
Benzo[a]pyrene	50-32-8	2.985E-10	kg/hp - hour
Benzo[b]fluoranthene	205-99-2	1.573E-10	kg/hp - hour
Benzo[ghi]perylene	191-24-2	7.763E-10	kg/hp - hour
Benzo[k]fluoranthene	207-08-9	2.461E-10	kg/hp - hour
Dibenz[a,h]anthracene	53-70-3	9.256E-10	kg/hp - hour
Fluoranthene	206-44-0	2.416E-08	kg/hp - hour
Fluorene	86-73-7	9.271E-08	kg/hp - hour
Inden[1,2,3-cd]pyrene	193-39-5	5.953E-10	kg/hp - hour
Phenanthrene	85-01-8	9.335E-08	kg/hp - hour
Pyrene	129-00-0	1.518E-08	kg/hp - hour

Part 4 criteria air contaminants (CAC) releases

Substance	Chemical Abstracts Service registry number (CAS RN)1	Emission factor (EF)2	EF units
Carbon monoxide (CO)	630-08-0	3.029E-03	kg/hp - hour
Sulphur dioxide (SO2)	7446-09-5	9.294E-04	kg/hp - hour
Oxides of nitrogen (NOx), expressed as nitrogen dioxide (NO2)	11104-93-1	1.405E-02	kg/hp - hour
Volatile organic compounds (total) (VOCs)	*	1.120E-03	kg/hp - hour
Total particulate matter (TPM)	*	9.974E-04	kg/hp - hour
Particulate matter less than or equal to 10 micrometers (µm) (PM10)	*	9.974E-04	kg/hp - hour
Particulate matter less than or equal to 2.5 µm (PM2.5)	*	9.974E-04	kg/hp - hour

Part 5 releases

Substance	Chemical Abstracts Service registry number (CAS RN)1	Emission factor (EF)(2)	EF units
Benzene	71-43-2	2.962E-06	kg/hp - hour
1,3-butadiene	106-99-0	6.207E-08	kg/hp - hour
Formaldehyde	50-00-0	3.747E-06	kg/hp - hour
Propylene	115-07-1	8.192E-06	kg/hp - hour
Toluene	108-88-3	1.299E-06	kg/hp - hour
Xylene (all isomers)	1330-20-7	9.049E-07	kg/hp - hour