Shell’s giant Prelude FLNG located offshore Australia will likely remain offline for a while following an incident earlier this month.
A Shell spokesperson told LNG Prime earlier this month that the firm had suspended production after an incident on December 2.
The spokesperson said that smoke detected in an electrical utility area had triggered the automatic fire detection and management systems on board the Prelude FLNG facility located some 475 km from Broome in Western Australia.
Shell had also decided to evacuate the majority of workers on board the FLNG as the unit requires only a skeleton crew during a production shutdown.
The following morning, Australian offshore regulator NOPSEMA had launched an investigation into the incident, it said in a report dated December 23.
The Shell Australia-owned and operated Prelude FLNG facility experienced an unplanned event that resulted in a complete loss of power at the facility, which subsequently led to unreliable and intermittent power availability over 3 days, the regulator said.
According to NOPSEMA, Shell made multiple attempts during this period to re-establish reliable power.
The regulator said it had established regular contact with Shell onshore management for updates on the offshore emergency situation and the activities underway to respond and recover, as the loss of power had impacted the “habitation and working conditions of the personnel on the facility.”
“By December 6, 2021, the failure to restore reliable power was seen to represent an ongoing impact and risk to the health and safety of the personal on the facility and NOPSEMA arranged to visit the facility,” it said.
The regulator’s inspectors visited the FLNG on December 8, returning two days later.
Moreover, the inspectors concluded that the operator “did not have a sufficient understanding of the risks of the power system on the facility, including failure mechanisms, interdependencies and recovery,” NOPSEMA said.
The regulator said that power failures directly impacted emergency response capability, operation of safety critical equipment, and evacuation of personnel by helicopter or boat.
Also, the failures impacted habitability of the facility for the personnel on board. This included essential services such as lighting, safety systems, communication systems, potable water systems, sewage treatment and HVAC.
NOPSEMA said that seven people were treated for heat-related conditions.
The regulator said that Shell is working to determine the cause(s) of the power system
issues that led to this incident.
However, the proposed scope of the investigation “does not provide for a thorough review of the evidence and root cause analysis of the entire series of events experienced during the incident and a review of the risks for future similar incidents and actions to mitigate them,” NOPSEMA said.
Prelude FLNG to remain shut until it is safe
Following the investigation, NOPSEMA has given four directions to Shell.
Under the first direction, Shell has to carry out a review or reviews of the incidents and associated consequences that occurred at the Prelude FLNG facility from December 2-6, including the issues identified in the NOPSEMA investigation report.
Based on the findings of the reviews from the first direction, Shell has to develop a detailed plan, schedule and commitment to timely implementation of all necessary corrective actions, NOPSEMA said.
“Prior to hydrocarbon production commencing, demonstrate to NOPSEMA’s satisfaction that the facility can safely recover essential power and associated essential services following a loss of power, and that the safety systems and essential support systems operate to maintain safety of personnel,” the regulator said.
As part of the fourth direction, Shell will have to send reports to the regulator.
“On the first business day of each month commencing March 2022 provide an update to NOPSEMA detailing progress under Directions 1 and 2 until NOPSEMA is satisfied under Direction 3,” the regulator said.
Production problems continue
Shell’s chief executive Ben van Beurden said earlier this year that the firm was working to bring Prelude to full production following a long shutdown due to an electrical trip in February last year.
Prelude delivered its first cargo in June 2019 after several start-up delays. The FLNG has the capacity to produce 3.6 mtpa of LNG, 1.3 mtpa of condensate, and 0.4 mtpa of LPG.
Shell operates the floating facility with a 67.5 percent stake. Japan’s Inpex holds a 17.5 percent stake, Korea’s Kogas 10 percent, and Taiwan’s CPC holds 5 percent.