Global shipping CO2 emissions decreased 1% last year as the Coronavirus pandemic curtailed 2020 shipping activity, according to maritime data provider Marine Benchmark.
CO2 emissions among the ‘Big-3’ – tankers, bulkers, and containers – actually increased 1.2%, with a 2.4% decline in container emissions offset by growth in the bulker and tanker sectors.
However, the smaller sectors reversed this growth, with cruise ship emissions experiencing the greatest contraction – down 45% – and with steep declines in ferries, roro’s and vehicles carriers consistent with the weak demand.
“The Coronavirus pandemic has had a varied effect on shipping, with Tankers and Bulkers generally performing well, while other sectors faced headwinds as consumer demand plummeted,” Torbjorn Rydbergh, Marine Benchmark’s CEO, noted.
“Whilst the overall result is a decrease in carbon emissions for last year, the effect may be temporary as the current recovery in global economic demand points to stronger 2021 shipping activity.”
The Gothenburg-based company said that vessel CO2 emissions were calculated from the carbon content of the fuel consumed.
Marine heavy fuel oil is approximately 86% carbon, which implies about 3.15 tonnes of CO2 per tonne of fuel consumed.
Since the carbon content of diesel (gas oil) is slightly higher, so too are the CO2 emissions per tonne of fuel consumed.
Actual vessel fuel consumption depends on a range of factors, but primarily the hull, engine and propeller design, vessel displacement, speed and fouling, as well as hydrological and meteorological conditions.
Marine Benchmark said that its proprietary algorithms estimate vessel fuel consumption by main and auxiliary engines, based on these factors, utilising hourly AIS data for all IMO registered ships spanning over 10-years.