Implementation of China’s domestic emission control area (ECA) may be counterproductive due to its narrow delineation around shores, says an International Council on Clean Transportation (ICCT) report.

The document: Delineating a Chinese emission control area: The potential impact of ship rerouting on emissions, notes of the Chinese ECA delineation being too close to shore.

“A delineation closer to shore is politically easier to achieve because China can unilaterally regulate ships in its territorial waters,” said the authors Xiaoli Mao and Dan Rutherford.

“However, a narrow ECA delineation may actually increase emissions if ship operators divert around the ECA to save on fuel costs, as ECA-compliant fuel is more expensive than traditional marine fuel.

“Therefore, China should consider how to delineate an ECA to prevent rerouting and ensure maximum emission reductions and public health benefits.”

The researchers studied the emissions reduction potential of four ECA delineation scenarios being (1) ECA extending 12 nautical miles (nm) from the coast, which is the boundary of China’s territorial sea; (2) ECA extending 24 nm from the coast, which is the boundary of China’s contiguous zone; (3) ECA extending 50 nm from the coast; (4) ECA extending 100 nm from the coast.

In summary, it found:

1. An ECA needs to be at least 100 nm from the coast to be most effective. Under a narrow ECA, ship operators may reroute some of their heavily frequented coastal voyages around the ECA to save money on fuel. The closer the ECA boundary is to the coast, the more ships will reroute. Therefore, narrower boundaries undermine the effectiveness of the ECA.
2. When ships bypass the ECA zone, they avoid environmental regulations, redistributing rather than reducing emissions. Worse, rerouting results in a modest (up to 2%) increase in fuel consumption compared to shorter, more direct voyages because rerouted voyages cover longer distances and, in some cases, require ships to speed up (and burn more fuel) to stay on schedule.
3. The more expensive ECA-compliant fuel is compared to globally compliant fuel, the more ships will reroute. Indeed, the decision to reroute is sensitive to bunker fuel prices. The larger that price differential, the wider the ECA boundary needs to be from shore to discourage rerouting.

The complete study is available here.

Photo credit: International Council on Clean Transportation
Published: 7 September, 2018