Deepsea container lines are unlikely to respond to cheaper bunkering by sailing faster and cutting transit times, according to SeaIntel Maritime Analysis.

Potential gains from reduced vessel strings would probably still be outweighed by network restructuring costs, said SeaIntel partner and CEO Alan Murphy.

"It is simply not worth it if the carrier does not expect a long-term gain from such a restructure," he said.

The Copenhagen-based research firm based its findings on three named container line services.

On 2M's AE/Swan Far East/North Europe service, speeding up round trip times from 11 to 10 weeks, and thereby cutting vessels on the route from 11 to 10, would produce annual savings of only US$2.3m, according to SeaIntel's analysis.

At an IFO 380 price of US$325/ton, speeding up the service would increase fuel costs from US$115m to US$132m, while vessel expenses such as capital and operating expenses would drop by US$19m through the removal of a ship.

But even this marginal saving could be lost if freight rates are eroded by a rise in effective route capacity through higher sailing speeds.