The fall-off in bunker prices could end up being bad news for owners of “eco” tonnage.

Until now, shipowners that invested heavily in fuel-efficient-containerships had been reaping a significant premium over older vessels in charter markets.

But today, that eco-differential is under threat following a drop of more than 20% in bunker costs over the past two months.

The additional revenues generated from fuel-efficient vessels are factored into charter rates, in what has become a two-tier market.

The