Fuel Oil
Fuel Oil (bunker fuel) is the oil burned to power a ship. It ranges from cheap, viscous heavy fuel oil (HFO) that must be heated and purified before use, through very low sulphur fuel oil (VLSFO), to cleaner marine gas oil (MGO) distillate. Heavy grades are treated on board in settling tanks and purifiers before reaching the engine.
Since IMO 2020, ships must burn fuel with no more than 0.50% sulphur (0.10% in emission control areas) unless they fit an exhaust scrubber. Fuel grade and quality drive cost, engine reliability and compliance, so fuel management is a central concern of ship operation.
Fuel is the single largest variable cost of operating a ship and the focus of the sulphur and carbon regulations, so choosing, buying and managing it well is where much of the operational money and compliance risk sits. Off-spec or badly managed fuel can also damage engines and cause a loss of power at sea.
What is the sulphur limit for marine fuel oil?
Since IMO 2020, a global cap of 0.50% sulphur, tightened to 0.10% inside emission control areas. Ships either burn compliant low-sulphur fuel or fit an exhaust gas scrubber to meet the limit.