On June 26, 2023, The Environmental Protection Agency wrote in the Federal Register they wanted comments on whether to extend the provision allowing for a 50-hour participation in Demand Response (DR) events.

The EPA reported on page 41368 of the Federal Register/Vo. 88, No. 121, that “Based on reported information, in the last few years, there appears to have been very little need for engines to operate for the purpose specified in the 50-hour provision.

“In light of this limited information on current use and the court’s vacatur of the 100-hour provision, it may be appropriate to eliminate the 50-hour provision, rather than seeking to revise it to tailor the provision more carefully to be consistent with its original rationale and the court’s decision on the 100-hour provision. Therefore, in this proposal, we are also soliciting comment and information on the 50-hour provision as we consider whether to propose removing these provisions from the CFR or whether we should propose changes to the provision…”

Briefly, the EPA was trying to eliminate the 50-hour provision since it had not been used much due to the grid’s general stability. I found that a tad puzzling since the grid is more vulnerable than ever, especially with cyber-attacks happening more frequently (Ask your utility rep what is being discussed in Public Service Commission meetings across the U.S.).

Fortunately for the public, the issues were at least temporarily settled since the EPA received over seventy responses stating it was a bad idea. But the battle, according to some, has just started. Behind closed doors I think you would hear that the main reasons some politicians got on the band wagon was to curtail running anything powered by diesel fuel, i.e., excess emissions!

Concerns vs. Facts

  1. CONCERN: DR will increase the hours on the generators thereby shortening their useful life. FACT: Duke Energy, as an example, since 2004 has called for an average of 22.6 minutes per year run time during Called Events (CE). If this were equated to a car running at 1800 RPM (the normal for 60hz current)—or about fifty miles per hour—it means an extra 7.5 hours over a 20-year period, or 375 miles. The required four 2-hour quarterly tests (QTs) used to verify the EPSS’s reliability would add only another 400 miles per year, or a total of 8,375 miles over a 20-year period without considering simultaneous required tests (see CONCERN 5 below).
  2. CONCERN: Hospitals do not like surprises and interruptions, especially during surgical procedures. FACT: Advance notices of CEs and QTs are always transmitted from the utility to the hospital several hours before. This is different from an actual power outage when no notice is given. If there is an interruption, it will be for only milliseconds, or if Closed Transition Transfer Switches (CTTS) are in place the transfer will be seamless. No 10-second blackouts during transfers.
  3. CONCERN: Excess engine run time increases emissions and contributes to pollution. FACT: Engines that qualify under EPA DR guidelines for some Tier 2 and all Tier 4 engines are deemed to be environmentally safe. In addition, since CEs are never called unless the utility senses an issue with the grid, running the qualified engines precludes the need for non-Tier rated engines (without emissions reductions components) from running, which reduces emissions that would occur during an actual outage. Therefore, DR is an EPA-friendly tool. Plus, any CE that lasts longer than normal means a utility outage has been prevented that would have resulted in having only one source of power.
  4. CONCERN: Hospital guidelines do not allow surgical procedures when generators are the only source of power. FACT: This is the law. However when there is a CE or QT, utility power is never unavailable at the automatic transfer switches (ATSs). Therefore, you always have two sources of power. And if you do lose utility power, you are already on emergency power or you have an immediate transfer to the emergency source, without the dreaded ten-second-or-less delays. If I am on the table under a neurosurgeon’s knife (some say it is needed), I would prefer to have both power sources available, so my case will not be interrupted. I will pay for the diesel fuel in any event.
  5. CONCERN: QTs increase my required testing by eighty tests over a 20-year period, not including the triennial test. FACT: Not really, if planned properly. All 80 tests can be completed during the normal and required monthly and triennial tests per NFPA 110, 8.4.1.1: “If the EPS is used for standby power or for peak load shaving, such use shall be recorded and shall be permitted to be substituted for scheduled operations and testing of the EPS, providing the same record as required by 8.3.4.
  6. CONCERN: If my T4 engines run out of Diesel Exhaust Fluid (DEF) during the tests they will shut down. FACT: NFPA 110, 5.6.5.5.1 (TIA) for 2025 states: “Where used for permanent Level 1 applications EPA mandated inducement engine shutdowns due to emission systems controls that are required on T4 certified engines with SCR shall be prohibited.

Summary

Demand Response improves the patient’s experience while protecting the environment—worthy of CEO appreciation.

  • Since some engine/generators will have to be replaced with T4 units, the cost can be substantial but EaaS programs and utility credits can increase and accelerate ROI. In some cases, monthly utility credits can reduce paybacks to less than two years.
  • Nameplate information should be used to obtain engine “build data”, so emissions figures can be reviewed by selected EPA officials to determine if an engine qualifies for a DR program.
  • An All-Hazards Risk Assessment (AHRA) should be performed to root out any Single Points of Failure (SPOF) in the Emergency Power Supply System (EPSS). Some utilities can impose suspension of credits if an EPSS cannot adequately perform during a CE or QT. Performing this assessment also provides a facility an opportunity to access budget requirements for the replacement of critical components.