JPS Completes Outage Investigation with Support from International Experts
Unique fault characteristic identified as key contributor to system shutdown
KINGSTON, Jamaica, July 15, 2026 — JPS has completed its investigation into the June 5 system shutdown and has submitted the report on its findings to the Office of Utilities Regulation (OUR) and the Ministry of Energy, Telecommunications and Transport (METT).
The investigation, which was conducted with the assistance of several international experts and firms, concluded that the system shutdown at 9:02 PM on Friday June 5, was caused by the unique characteristic of a lightning strike-induced fault at the Company’s Hunts Bay substation. The fault remained on the grid for an extended time, creating instability and the rapid tripping of generators, which cascaded into the island-wide shutdown. Service was restored to all customers by 6:34 AM on June 6.
It was the first fault of this nature ever recorded on the JPS transmission system. The rare highly resistive and evolving fault condition was not cleared by the network’s primary protection scheme. Additionally, the back-up protective devices operated slower than anticipated due to the unique highly resistive fault. This longer than anticipated clearing of the fault, coupled with generating units tripping offline (some prematurely), resulted in the system automatically shutting down.
International Expertise
The extensive technical investigation was done by JPS’ engineering teams and international experts, who brought a wide range of experience and expertise to the process. A team from Mitsubishi Electric Power Products Inc. conducted a steady state and transient stability analysis review of the system; Danovo Energy Solutions (formerly Quanta Services) did root cause analysis; Schweitzer Engineering Laboratories (SEL) and General Electric (GE) both conducted a performance analysis and review of the protective devices.
JPS also received independent assessment from two leading industry and utility experts with experience at the utility, state and federal level with widespread system outages in the United States. Their experience includes investigations into the Northeast Blackout of August 2003, which plunged 50 million customers in the United States and Canada into darkness; the Texas Power Crisis in 2011; and the 2011 wide area shutdown in the Southwest that plunged San Diego into darkness. They have also served in leading roles on various committees and councils responsible for establishing standards for grid operations and protection systems in the US, including the National Electric Reliability Cooperation (NERC), the Northeast Power Coordinating Council (NPCC), and the Institute of Electrical and Electronics Engineers (IEEE).
“It was important that we reached out to global experts to work along with our team, to very quickly understand what happened,” said JPS’ President and CEO, Hugh Grant, “and even more importantly, that we were able to act on some findings right away.”
Immediate Corrective Action
JPS has already taken steps to implement some of the recommendations of the panel of experts that reviewed the outage, to strengthen the network protection schemes and mitigate a recurrence of an incident of this nature. This includes the replacement of primary protection equipment, a review of the protection settings and schemes to react to unique faults of this nature, and acceleration of the ongoing System Protection Modernization Program. A number of additional measures are being implemented to enhance system protection, monitoring, and overall network performance.
JPS will be working with Independent Power Producers (IPPs) to review the protective settings of generators, to ensure that all generating plants operate as expected, in keeping with fault ride-through requirements of the Electricity Grid Codes. This, as the investigation revealed that some units tripped earlier than expected in reaction to the fault conditions.
The Company will also work closely with the OUR and the Ministry on an action plan to implement recommendations from the investigation, following on their review of the 350-page report.
“We want to thank our customers for their patience and understanding, as we worked through this unfortunate incident,” the JPS CEO said. “A key outcome was a rapid restoration process. We were able to immediately activate our Incident Command, with crews dispatched to key locations, and the first set of customers restored within one hour of the event. But this is not enough. Our aim is continuous improvement. Just as we do for hurricanes, we will take all the learnings from this event: from our own experience, the advice of the global experts, and the reviews of the OUR and the Ministry. We will partner with key stakeholders, including the OUR and the Ministry of Energy, to strengthen Jamaica’s electricity network to deliver a safe, reliable and resilient electricity service,” he emphasized.
