The Environmental Protection Agency (EPA) requests comments on the provision specifying that emergency engines can operate up to 50 hours per year for non-emergency use. Comment submissions will be used to evaluate the need for the provision, including by assessing how often and under what circumstances stakeholders use it.

The EPA also proposes to amend the reciprocating internal combustion engine (RICE) electronic reporting requirements. According to the EPA, adding electronic reporting will simplify reporting for stakeholders and enhance data availability to the EPA and the public.

The proposed rule can be read in its entirety on the Federal Register. Comments are due to the EPA by August 25, 2023. Motor and Generator Institute requested a 60-day extension. Click here to download a copy of the request.

50-Hour Provision

In 2013, the EPA finalized a rule that changed the stationary engine NESHAP and NSPS requirements regarding limitations on the hours of operation of emergency engines. Before the 2013 amendments, emergency engines were restricted to 100 hours of operation per year for maintenance and testing, of which 15 could be used for emergency demand response. These provisions were often called the “emergency demand response” or “100-hour” provisions.

The 2013 rule continued to restrict emergency engines to a collective 100 hours of operation per year for maintenance, testing, or emergency demand response but removed the 15-hour limit for emergency demand response. The 2013 rule specified that emergency engines could operate for up to 50 hours per year in non-emergency situations (counted as part of the 100 hours) and that the 50 hours could be used to supply power as part of a financial arrangement with another entity if the following conditions are met:

  1. The local balancing authority or local transmission and distribution system operator dispatches the engine.
  2. The dispatch is intended to mitigate local transmission and/or distribution limitations to avert potential voltage collapse or line overloads that could interrupt power supply in a local area or region.
  3. The dispatch follows reliability, emergency operation, or similar protocols that follow specific North American Electric Reliability Corporation (NERC), regional, state, public utility commission, or local standards or guidelines.
  4. The power is provided only to the facility itself or to support the local transmission and distribution system.
  5. The owner or operator identifies and records the entity that dispatches the engine and the specific NERC, regional, state, public utility commission, or local standards or guidelines being followed for dispatching the engine.

The EPA is evaluating the need for this provision, including assessing how often and under what circumstances stakeholders use the 50-hour provision. According to the EPA, reported information in the last few years shows little need for engines to operate for the purpose specified in the 50-hour provision.

Electronic Reporting

The EPA is proposing that owners and operators of stationary engines subject to New Source Performance Standards (NSPS) or National Emission Standards for Hazardous Air Pollutants (NESHAP) submit electronic copies of certain documentation through the EPA’s Central Data Exchange. The proposed rule requires that performance test results be collected using test methods that are supported by the EPA’s Electronic Reporting Tool (ERT), as listed on the ERT website.

For annual and semiannual compliance reports, the proposed rule requires that owners and operators use the appropriate spreadsheet template to submit information to the Compliance and Emissions Data Reporting Interface. The docket for this action includes a draft version of the proposed template(s). Users can download a copy of each from the Federal Register. The EPA requests comments on the content, layout, and overall design.

The EPA states: “The electronic submittal of the reports addressed in this proposed rulemaking will increase the usefulness of the data contained in those reports, is in keeping with current trends in data availability and transparency, will further assist in the protection of public health and the environment, will improve compliance by facilitating the ability of regulated facilities to demonstrate compliance with requirements and by facilitating the ability of delegated state, local, Tribal, and territorial air agencies and the EPA to assess and determine compliance.


Motor and Generator Institute prepared a template for interested parties to request an extension. The public’s participation and feedback are vital to the decision-making process, and all stakeholders are encouraged to share their insights. Please fill in your name and email address below to receive a copy of the template and instructions to submit your comments.

Danny Chisholm

Since 2003, Dan has been an emergency power consultant, performing risk assessments, commissioning, decommissioning, and training for hospitals, data centers, and universities. He is a member of the Technical Committee responsible for NFPA 99, Health Care Facilities Code, Electrical Section, NFPA 110, Standard for Emergency and Standby Power Systems, NFPA 111, Standard for Stored Electrical Energy and Standby Power Systems, and an instructor for the Certified Healthcare Emergency Power Professional (CHEPP) program.