The Potential-to-Emit (PTE) Calculator is a simple tool for the agriculture industry to perform a quick criteria pollutant PTE estimate for engines.
The PTE Calculator can:
- Help you estimate the potential-to-emit (PTE) emissions of your stationary engine(s)
- Compare these emissions to Title V emission thresholds for the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD)
While these values may be used for your information, you should always confirm your calculations and your facility's PTE status with the SJVUAPCD staff.
This calculator is only an estimate for pump engines or other internal combustion engines. If your facility has other equipment that emits criteria pollutants such as oxides of nitrogen, oxides of sulfur, particulates, volatile organic compounds and/or carbon monoxide, the emissions from that equipment need to be accounted for as well.
How to Use the Calculator
Detailed instructions are included within the Excel file as well.
- Select the type of engine. These are pull-down menus with a selection of various types of engines in two categories:
- Other (gasoline, natural gas, propane)
- Input the number of engines.
- Input the typical hours of operation over one year (actual data, if available).
- Input the horsepower rating of each engine.
- Input the engine load factor, if known. The default is 65 percent, but this can be changed. Load factor is defined as the amount of power used by the engine to do work, expressed as a percentage of the maximum.
- Read the resulting actual and potential emissions. If the actual emissions are greater than 50 percent of the Title V thresholds, you MAY be subject to Title V. The next step is to analyze potential emissions (PTE).
- If the PTE emissions exceed the Title V thresholds, you are likely to be subject to Title V permit requirements.
- Contact the SJVUAPCD Small Business Assistance to verify agreement with your results. You may be able to take limits on your engines to avoid the need for a Title V permit; this is called a "synthetic minor."
The US EPA regulates five criteria pollutants listed below:
- VOC = Volatile Organic Compounds
- NOx = Nitrogen Oxides
- SOx = Sulfur Oxides
- CO = Carbon Monoxide
- PM = Particulate Matter
This document and the PTE Calculator only consider criteria pollutants.
Hazardous Air Pollutants
The US EPA also regulates Hazardous Air Pollutants (HAPs), since they contribute to health risks. For example, diesel engines emit both criteria pollutants and HAPs. To prepare a complete Title V applicability analysis, the Hazardous Air Pollutant potential to emit should also be examined.
What is Title V?
Title V is a federal operating permit program. Federal Title V permits are required for large "major" sources of air pollution. If your agricultural operation is determined to be a major source, the District must issue a Title V permit instead of the standard District permit. Title V permits are subject to the Environmental Protection Agency (EPA) and public review, and generally contain more monitoring, record keeping and reporting requirements based on federal regulations.
The US EPA uses a facility's "Potential to Emit" (PTE) to determine whether that facility is subject to Title V permit regulations. The Potential to Emit is a facility's emission level if it operated at maximum capacity. It is the maximum amount of emissions that a facility can emit; it is not the facility's actual emissions. One of the first steps that any facility needs to do is calculate its PTE to find out whether it is subject to EPA Title V air permits.
Are You Subject to Title V?
- If a facility reports actual emissions that are greater than 50 percent of the major source thresholds, it may be subject to Title V and should calculate PTE. Note that SJVUAPCD requires a District permit for equipment with reported emissions that are greater than 50 percent of the major source thresholds.
- If the potential to emit (PTE) (of any criteria pollutant or hazardous air pollutants) of all the sources in a facility are greater than the major source PTE thresholds, the facility is subject to Title V permitting requirements. The SJVAPCD currently assumes a 65 percent load factor and 6,000 hours/year as default values to represent an agricultural operation at maximum capacity. Note that an operator can take permit limits to limit maximum hours of operation (less than the default value of 6,000 hours) to reduce the PTE.
Attainment status is a rating or categorization assigned to an air district based on how close it is to meeting the ambient clean air standards. San Joaquin Valley APCD recently petitioned the California Air Resources Board (CARB) to change it's designation from "Severe" to "Extreme” non-attainment. The move to "Extreme" rating will not go into effect until SJVUAPCD amends its rules to reflect this change. The major source thresholds vary by attainment status; see the table above.
This calculator, which was prepared by Yorke Engineering LLC, is for emissions estimation purposes only and should not be solely relied upon or used as an endorsement, approval or guaranty of compliance with Title V or any other air quality regulations. All calculated results should be reviewed with SJVUAPCD staff to ensure that all inputs reflect the most up to date air district policies and regulations. Use of the information and data from this Calculator is at your sole risk. SoCalGas makes no representations or warranties, whether expressed or implied, and does not assume any legal liability or responsibility for the accuracy, completeness or usefulness of any information, data or process disclosed or derived from the use of this Calculator. Contact the SJVUAPCD for more detailed information.