Are scrubbers really good for the environment?

THERE are two main challenges facing shipping that relate to emissions. In just over four months' time, a global sulphur limit of 0.5 per cent for marine fuels will come into force. That is centre stage right now.

In the longer term, the much more challenging task will be to drastically cut CO2 (carbon dioxide) emissions from ships.

These are different challenges but there are clear policy overlaps for governments and for shipowners. For example, the use of liquefied natural gas (LNG) has been mooted as not only solving the sulphur problem but also acting a bridging fuel towards a carbon- free future.

There have been challenges to this view, often based on the issue of "methane slip" where a portion of the natural gas escapes into the atmosphere during the extrac…