Six European ports have launched an initiative to reward environmentally clean ocean-going vessels.

Starting from 1 January 2011, ports at Le Havre, Bremen, Hamburg, Antwerp, Amsterdam and Rotterdam will offer discounts on port dues to cleaner vessels in a bid to cut emissions.

The ports have also developed an environmental ship index to calculate a vessel’s green performance, aiming to encourage owners to speed up emissions cuts on a voluntary basis.

The vessels are expected to cut nitrogen oxide (NOx), sulphur oxide (SOx) and particulate matter emissions.

The participating vessels will receive a certificate detailing their environmental performance grading them between one and 100, according to