Recent analysis by the legal firm HFW has highlighted a rise in claims involving fuel degradation on dual-fuelled LNG carriers, a pattern also observed in recent UK Club claims, leading to operational complications and legal disputes.
According to the UK Club, this issue often occurs when vessels primarily use LNG, resulting in extended onboard storage of fuels such as VLSFO.
Prolonged storage can lead to degradation, potentially necessitating de-bunkering or causing mechanical failures.
Preventing fuel degradation:
- Regularly recirculate fuel to avoid stratification, where the piping layout permits.
- Maintain optimal storage temperatures, supported by tank heating alarms and charter party clauses that set limits on pour and cloud points.
- Regularly drain tank bottoms to reduce water accumulation and microbial growth, although this may not be feasible in all tanks.
- Consider using additives, provided they are approved by the engine manufacturer.
- Employ monitoring tools such as water-finding paste alongside periodic tank cleaning.
Early detection of degradation:
- Conduct visual inspections for sludge, discoloration, or unusual odours.
- Supplement visual inspections with laboratory testing every three to six months.
- Monitor key parameters including viscosity, Total Sediment Potential (TSP), water content, microbial contamination, and Total Acid Number (TAN).
Handling aged or degraded fuel:
- Document all mitigation steps thoroughly, including photographic evidence and test results.
- Promptly notify charterers and the Underwrites.
- In complex cases, involve fuel experts to assess the situation and guide next steps.
Furthermore, it is recommended that charterparty agreements be updated to address explicitly the evolving risks associated with multi-fuel use.
With dual and tri-fuelled ships rapidly becoming the standard for environmentally compliant operations, owners and charterers must collaborate on fuel management, both in practice and in contracts.
It is no longer sufficient to focus only on the delivery quality of fuel; onboard storage, monitoring, and response protocols are now a critical part of ensuring operational reliability and claim defensibility.