Marine diesel must be 10 times cleaner by 2014

Over 15,000 diesel-powered vessels could be forced to use fuel with 90 per cent less sulphur, after a trial found the cleaner alternative had no impact on vessels' mechanics or consumption, under a government proposal.

However, some operators fear that the cleaner diesel will push up their running costs - despite government assurances to the contrary.

The proposal will be tabled to the legislature this year and will force operators of vessels, including ferries, high speed boats, barges, tug boats and cross border vessels, to use diesel containing no more than 0.05 per cent sulphur from 2014.

The cap is 10 times stricter than the current 0.5 per cent limit on sulphur in marine diesel.

However, the upgraded fuel still has 50 times more sulphur than the Euro V diesel being used for road transport. That diesel only has 0.001 per cent sulphur.

In a paper submitted to lawmakers yesterday, environment officials said a trial completed in January this year found the cleaner fuel would not damage older engines.

The trial, conducted by University of Hong Kong specialists, also confirmed there was no significant change in fuel consumption or power output after the switch.