WHAT IS IT?
Fuel oil is a heavy, viscous residual product from crude oil refining — what remains after lighter fractions (gasoline, diesel, naphtha) are extracted. It is the primary fuel for large ocean-going vessels and industrial boilers.

TYPES BY SULPHUR CONTENT (post IMO 2020)
HSFO (High Sulphur Fuel Oil): >3.5% sulphur. IFO 380 and IFO 180. Now restricted to ships with scrubbers (exhaust gas cleaning systems).
VLSFO (Very Low Sulphur Fuel Oil): <0.5% sulphur. Introduced to comply with IMO 2020 regulations. Most common bunker fuel since 2020.
ULSFO (Ultra Low Sulphur Fuel Oil): <0.1% sulphur. Required in Emission Control Areas (ECAs) — North Sea, Baltic, North America.
MGO (Marine Gas Oil): Distillate, <0.1% sulphur. Used in ECAs and smaller vessels.

IMO 2020 IMPACT
IMO 2020 regulation (effective January 1, 2020) cut the global sulphur cap from 3.5% to 0.5%. This caused a massive market restructuring:

Demand shifted from HSFO to VLSFO overnight

HSFO spread to VLSFO widened significantly

Scrubber-fitted ships maintained HSFO economics

KEY USES


Marine shipping (primary use — 300+ million tonnes/year)

Power generation in developing markets

Industrial boilers and furnaces

Feedstock for secondary refining

TRADE CORRIDORS


Major bunkering hubs: Singapore (world's largest), Rotterdam, Fujairah, Houston
Tetra relevance: Singapore is world's #1 bunkering port. Critical for any shipping-related trade.

SPECIFICATIONS (VLSFO ISO 8217 RMG 380)

Sulphur: max 0.50%

Viscosity at 50°C: max 380 cSt (IFO 380)

Density at 15°C: max 991 kg/m³

Flash point: min 60°C

Water content: max 0.5%

Ash: max 0.10%

fuel oil bunker HSFO VLSFO IFO380 IMO 2020 marine fuel