Operator error on the part of Bahamas Power and Light (BPL) led to the September 2018 fire at the Clifton Pier Power Station that sidelined its two largest generators, an investigation into the incident concluded.
The report on the fire, obtained by The Nassau Guardian, revealed that either BPL’s attempt to troubleshoot an engine it had brought online, contrary to the manufacturer’s established protocol, or manipulation of a critical engine component during maintenance caused the fire.
The manufacturer of the generators said the proper procedure to troubleshoot the engine would have taken BPL no more than 30 minutes to complete.
The report also found that the engine component in question could not be found in the aftermath of the fire.
Those two generators, 21 and 17 years old at the time of the fire, represent a loss of 63 megawatts (MW) of generation.
The report concluded that though the fire was the result of operator error, it was still eligible for a certain level of coverage under BPL’s insurance policy with J.S. Johnson Insurance Agents and Brokers.
The report also concluded that the fire was not the result of gross negligence on the part of BPL.
The report said that it would cost $33 million to replace the generator that was destroyed, repair the one that was damaged and bring the entire plant at Station C fully online.
The estimated time given to restore the entire facility was 21 months.
The report was prepared by Rimkus Consulting Group out of Florida.
It was completed on March 11, 2019.
The fire occurred on September 7, 2018 at Station C at the Clifton plant.
Two Man 10K80 diesel alternators, DA11 and DA12, were housed in the station.
The engines run on heavy fuel oil, commonly known as Bunker C.
The station also had its own control room, switch gears and supporting equipment, such as an overhead crane critical to performing repairs on the generators.
On the night of the fire, both engines were offline, according to a September 11, 2018 memo written by BPL Chief Financial Officer Chandrice Ferguson.
DA12 was out of service for lubrication oil contamination.
DA11 was out of service for about three months for repairs to its turbocharger by the manufacturer, MAN Energy Solutions.
Those repairs were completed by that Friday.
Shortly after noon that day, engineers at Clifton attempted to start DA11 but found that a solenoid needed to be repaired.
That repair was completed by 4:15 p.m.
At 10:21 p.m., DA11 was brought back online.
It is unclear who gave that directive.
Engineers found that cylinders number two, three, five and 10 of the engine were experiencing low combustion temperatures.
BPL engineers concluded that this was the result of low fuel pressure across the cylinders and decided to manually operate the puncture valve on the fuel pump of each cylinder.
BPL engineers would do this by removing the air control line on the cylinder to attach an air puncture tool while the engine was still running.
According to BPL engineers, while operating the puncture valve on cylinder three, a plug shot out of the top section of the fuel pump, releasing pressurized fuel that sprayed up to the ceiling and fell back down, hitting the hot exhaust manifold, igniting and causing a fire.
Engineers called the control room, leading the control room operator to hit the emergency stop button.
Two engineers then raced to grab fire extinguishers to put the fire out.
Though the emergency stop button was engaged and the fire at the exhaust manifold was extinguished, fuel was still gushing from DA11’s fuel pump.
In order to stop the flow of fuel, engineers had to manually stop it at the local electrical panel.
By that time, embers from the fire had dropped into the basement of Station C, where approximately four feet of residual oil and sludge sat in the catchment trenches.
BPL personnel then rushed to the basement and retrieved fire hoses from the basement and attempted to extinguish the fire.
Their attempts proved futile.
The fire grew and spread along the cable trays up to the rear of DA11.
At that point, BPL decided to call the Fire Services Division of the Royal Bahamas Police Force (RBPF).
As they waited on the fire department, BPL personnel still attempted to battle the fire.
However, the fire eventually burned through the station’s electrical wiring, killing power to the water pumps.
The fire department arrived at 11:06 p.m.
Firefighters attempted to extinguish the fire with water and foam, but they quickly ran out.
The fire department at Lynden Pindling International Airport was then contacted to assist.
Those firefighters arrived at 12:12 a.m.
At 2:45 a.m. Saturday, the all clear was given that the fires were under control.
DA11 was damaged beyond repair.
DA12 was minimally damaged, according to investigators.
The crane required for maintenance on the engine was also rendered useless.
Forensic engineers examined both DA11 and DA12 as well as the entirety of Station C in the aftermath of the fire for insurance purposes.
They were unable to locate the plug that BPL reported blew out of cylinder three of DA11.
They also found that there was no physical damage on the valve plug threads to indicate that the threaded connection failed.
“The cause of the plug reportedly blowing out of the puncture valve was indeterminate,” the report said.
“The available physical evidence was consistent with operator error, due to the manipulation of the plug either during off-line puncture valve maintenance or at the time the puncture valve was being manipulated with the engine operating.
“No physical evidence was observed that would lead us to consider this to be gross negligence.”
However, when investigators spoke with a consultant from MAN, it was made clear that the puncture valve should not have been manipulated while the engine was running.
“No user procedure calls for the removal of the plug,” the report found.
The report also said, “MAN has no procedure for manually manipulating or working on the puncture valve with the engine running.
“If low temperatures in the cylinders are observed and suspected from the puncture valve allowing fuel to recirculate, the engine can operate at the reduced load.
“To regain full power from the fuel recirculation restriction, MAN recommends that the engine be shut down and the puncture valve assembly replaced.”
MAN’s engineer noted that “the puncture valve assembly takes approximately 20 to 30 minutes with the engine off”.
The investigators found that the components directly attached to DA11 – the fuel injection, exhaust, cam shaft, turbochargers and electrical and control elements – were “completely destroyed” by the fire.
They also believe that the exposure to various high temperatures impacting different parts of the engine for different durations may have warped and damaged DA11’s engine block and its components.
The report concluded that DA12’s “engine proper” appeared to have “minimal damage from the fire event”.
“Instrumentation, electrical and plastic components were damaged consistent with the fire event,” the report said.
“DA12 was partially dissembled with a cylinder head removed at the time of the fire; therefore, internal damage on DA12 may have occurred.
“However, note that the lower block of DA12 was in close proximity to the basement auxiliary equipment that was consumed by the fire event.”
The report said further evaluation would be needed for a more accurate damage assessment of the inside of the engines.
The report noted that a functional crane would be required to do so.
The assessment of the crane replacement was valued at $473,000 with a delivery time of 10 to 12 weeks after order.
The Guardian understands that BPL has not ordered a replacement crane for Station C.
The fuel oil system for the station, as well as the starting air system, the lube oil system, the instrument air system, the station air system, the water treatment system, the cooling system and equipment hoists were all destroyed in the fire.
Replace and repair
DA11 was 21 years old and was installed in 1997.
It was insured at a value of $12.4 million.
DA12 was 17 years old and was installed in 2001.
It was also insured for $12.4 million.
The report concluded DA11 needs to be replaced, but DA12 can be repaired.
The cost of bringing Station C back online was estimated at $33,218,278 with a timeline of less than two years.
DA11 could reportedly be replaced at a cost of just over $14 million for materials and labor.
DA12 could reportedly be replaced at a cost of just over $9.5 million for materials and labor.
The controls and electrical components for both engines could reportedly be replaced at a cost of just over $800,000.
The station building and electrical repairs and replacement could reportedly be done at an estimated cost of just over $2.1 million.
Indirect allowances, subcontracted services and demolition were estimated at $6.6 million.
“The replacement of DA11 is based on the proximity and duration the engine had to cylinder three and the basement fire events,” the report said.
“The DA11 engine block assembly was exposed to various high temperatures acting on different sections of the engine for various durations.
“This differential in temperature and fire/heat durations may have warped and damaged the engine block and its components, requiring a complete replacement.”
The report concluded that because DA12 was less badly damaged because it was more distant from the basement fire, it should be able to be repaired.
“The repair of DA12 is based on a tear down and rebuilding of the engine block and internal components, the rebuilding of the fuel injection, exhaust, cam shaft, turbochargers, and the replacement of the electrical, control components,” the report said.
Officials at BPL have repeatedly refused to release any reports into the fire at Station C, citing Cabinet secrecy and supposedly delicate negotiations with the insurance company.
Sources within BPL have confirmed that there has been no remediation done at Station C in what has been nearly a year since the fire.
BPL has been plagued by generation shortfalls for months, leading to continued load shedding on New Providence.
At a press conference to discuss load shedding at BPL’s Clifton plant earlier this month, BPL officials refused to talk about the fire and claimed it has nothing to do with the generation problems the company is currently facing.