Tank-to-Wake (TtW)

Tank-to-wake is the onboard stage of fuel lifecycle accounting: the greenhouse gases released when the fuel is burned in the ship’s engines and boilers, including the CO2 of combustion plus methane slip and N2O. It is the only stage older measures like the EEDI captured, which flattered fuels whose carbon was emitted upstream instead. Combined with well-to-tank it gives well-to-wake, the basis on which the IMO Net-Zero Framework and FuelEU Maritime judge a fuel.