JPS implements recommendations following assessment of  island wide black out

The Jamaica Public Service JPS said it has already implemented, some recommendations for corrective measures, in the wake of a detailed assessment of the island wide black out last month.

This is being done to strengthen the network protection schemes and mitigate the recurrence of an incident of this nature.

In a statement, the JPS said it has completed the outage investigation, with support from international experts, and that a unique fault characteristic, was identified as a key contributor to system shut down.

The JPS submitted the report on its findings to the office of utilities regulation (OUR) and the Ministry of Energy.

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.

The JPS said it was the first fault of this nature ever recorded on the transmission system.

It said 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. 

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.

The JPS said immediate corrective action included 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 said it will be working with independent power producers 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 Energy  Ministry on an action plan to implement recommendations from the investigation, following on their review of the report.

JPS’ President and CEO, Hugh Grant, noted that while the company responded quickly and was able to restore power to customers within hours this is not enough.

Grant said the aim is continuous improvement, adding that similar to what happens for hurricanes, the JPS will learn from this event, take advice from experts, and partner with key stakeholders, to strengthen Jamaica’s electricity network and deliver a safe, reliable and resilient electricity service.