Drewry Reports Big Drop in Box Ships CO2 Emissions, Reduced Bunker Consumption

Fuel-efficient ships, slow-steaming, and government restrictions were behind the reduction in box ship's bunker consumption.

Containership CO2 emissions on Asia-North Europe round-voyages have dropped by 35 percent over a five-year period to 2013, according to a brief published in April by Drewry Supply Chain Advisors.

Drewry attributes the decline to a corresponding drop in fuel consumption and attributes this to three factors: slow-steaming; the trend towards larger, more fuel-efficient ships; and restrictions placed by government on ships coming into the ports.

Drewry calculates that for the 35 percent drop in CO2 on the Asia-North Europe route, the average ship size on that route increased by 40 percent over the five-year period.

Although more recent data was not available to Drewry, the brief posits that because average containership sizes increased by another 23 per cent between 2013 and 2015, "it follows that emissions per unit of capacity must have continued to fall."

The Drewry analysts point out that global container trade grows by four-five per cent annually, so fuel efficiency gains of six-eight per cent yearly mean that fewer tonnes of CO2 are pumped into the atmosphere than before.

"For example, in 2014, Maersk Line carried seven per cent more containers than the year before and reduced fuel consumption by container shipped by eight per cent – resulting in a net fall in the amount of fuel consumed and in associated CO2 emissions."

The most obvious benefit of reduced fuel consumption is reduced operating costs, and Drewry cites Maersk as having 2012 fuel costs US$1.6-billion less than the company would have paid had it not achieved a 25 per cent reduction in CO2 per container since 2007.

The brief also mentions pollution reductions in ports, and cites the Port of Los Angeles achieving a drop of diesel particulate matters and CO2 emitted by ocean going ships during a five year period by 68 per cent and 22 per cent respectively.

The brief notes that sulfur emissions are now being tackled by the shipping industry but warns that government rules on the use of low-sulfur fuel "could cost shipping lines and shippers more money due to the price differential between cleaner bunker oil and high-sulfur oil."

Earlier this month, Drewry said there was clear evidence that box carriers were passing on the savings from low bunker prices.