Few ship operators have felt the impact of new bunker rules in Emission Control Areas (ECA) more than short-sea and project cargo specialist Carisbrooke Shipping.

The Isle of Wight-based firm operates a diverse fleet of some 60 vessels, many of which are running in and out of Europe’s ECA on a constant basis and some of which also operate in North America’s ECA.

Under the new regulations, ships burning heavy fuel oil with significant sulphur content must now switch to marine gasoil (MGO) containing no more than 0.1% sulphur whilst operating in ECA waters. For many vessels, this has required a division of bunker tanks and a reorganisation of fuel supply arrangements to the main engine.

The first three months of ECA operation, however, have run without a hitch, according to Carisbrooke Shipping Chief Executive Robert Wester, despite reports of problems experienced by some ship operators in both Europe and North America. ECAs entered force on both sides of the Atlantic on January 1.

“We are delighted to be able to report that our first three months of ECA operation have been problem-free,” says Wester. “We put this down, in part, to careful preparation supported by the skill and diligence of our seagoing staff. Despite the new challenges, we have continued to offer our usual high standards of service to charterers and end users.”

There are various operational issues associated with fuel switching. The fuel system set-up on board ships, other than sisters, varies, and seagoing engineering staff must focus on suitable preparation for changing fuels.

Temperature and viscosity are two of the variables. Heavy fuel oil and low-sulphur distillates work at different temperatures and rapid changes in fuel supply to the main engine can risk thermal damage to machinery components. During change-over, the two fuels are inevitably mixed, leading to the possible clogging of filters and, in the worst case, main engine failure.

Fleet Technical Director, Martin Henry, explains the company’s strategy:
“Knowing what kind of serious failures and problems can occur during the extremely critical period of fuel change-over if not managed well, we decided that careful preparation was a priority, not least because the regulations were to enter force at the very worst time of the year when weather conditions are often at their most severe,”

He comments:
“Bearing in mind that many of our vessels are constantly in and out of ECA-regulated waters, we assessed each group of ships in our fleet to see what modifications would be required in terms of fuel tank allocation and piping arrangements,” he continues. “On some ships, there was a considerable amount of work needed – seven vessels needed MGO coolers, for example. But our Green ships, on the other hand, were built with the new fuel regulations in mind and required no modifications.”

“We seconded two serving Senior Chief Engineers to Head Office and between them, they visited all of our vessel series, carrying out actual change-overs to and from MGO in order to draw up suitably detailed change-over procedures. These vary,” Henry continues. “because on board some of the older vessels, there is limited tank capacity for distillate fuel and more time is required for the change-over process. On others, we had to reorganise fuel supply pipework where this was economically viable.”

CEO Wester outlines important differences in Carisbrooke’s operation as compared with deep-sea ship operators. For a start, he says, short-sea operators have a more limited range of options when it comes to compliance with the new regulations.

Unlike deep-sea operators, the economics of scrubber installation to clean exhaust gas, or engine retrofits to burn alternative fuels such as liquid natural gas simply don’t stack up. In relatively small ships, there are also space and stability constraints relating to scrubber installations, Wester points out.

The short-sea market is fiercely competitive, margins are thin, and additional investment on this scale cannot be passed on to charterers in the form of higher freight rates. Significant capital investment would never have paid back on board many ships in the fleet. Nevertheless, Henry estimates that the compliance process has still cost the company in excess of €0.5m, though he is confident that this investment has led to safer, greener more efficiently-run vessels and company overall.