MEASUREMENT AND REPORTING OF CO2 EMISSIONS FROM GAS CARRIERS

This is one more volume relating to the modern carriers of the liquefied gases. It shall be noted that the guidance provided in the pages of this official SIGTTO publication is intended to cover the CO2 emissions from the LNG carriers and no other greenhouse gases. The authors have focused on the emissions resulting from the combustion of the hydrocarbons during the regular operation of the vessel.

The trainees are expected to possess some very basic understanding of how the LNG carriers operate. Normally, the main and auxiliary engines and boilers will be considered typical sources of the CO2 emissions, together with the IGG, or Inert Gas Generator, and GCU, standing for the Gas Combustion Unit. In turn, the CO2 emissions can be measured using one of two available methods, namely the direct measurement, or measuring the consumption of the fuel on board with subsequent calculation of the CO2 through the so-called carbon emission factor.

The present volume mainly addresses the second method. The fuel consumption on board is usually monitored through the bunker delivery notes, or calculations based on the tank measurements of either fuel tanks or cargo tanks, should the cargo be used as a fuel. In addition to that, this can be evaluated using the flow meters.