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Wärtsilä Slow Steaming Upgrade Kits To A.P. Moller

axel_maersk_webWärtsilä has signed a major contract with the A.P. Moller Maersk Group (APMM). The order covers the installation of Wärtsilä Slow Steaming Upgrade Kits to 34 more of the company’s large container vessels, following the successful installation and testing on one of the fleet’s sister vessels in late 2009. Slow steaming has become a recognized means of operating in order to reduce fuel consumption.

The 34 ships to be fitted with Slow Steaming Upgrade Kits are powered by Wärtsilä RT-Flex96C and RTA96C main engines with 10, 11 and 12 cylinders. Applied to the Wärtsilä low-speed main engines, the upgrade kits will produce major savings in the ships’ fuel consumption while also cutting carbondioxide emissions. It is anticipated that as a result of installing the kits, these vessels will achieve fuel savings of between 3% and 7% with the engine running at low load. These savings are in addition to those attained through reducing speed to slow steaming operation. The fuel savings are achieved by cutting out one of the engine’s turbochargers at engine loads of less than about 60% (this figure is valid for engines with three turbochargers), thereby providing greater scavenge air pressure for better combustion and optimal engine component temperatures. This cut out is controlled and fully automated.

Mr Palle Laursen, Vice President, Maersk Line:”During recent years we have been continuously looking into solutions that improve the overall fuel efficiency and emissions of our vessels. As operators and charterers of the world’s largest container ships fleet, we soon recognized the savings potential of optimizing ship speed, and we have been a forerunner in the wide implementation of slow and super slow steaming as a means for substantial fuel consumption and emissions reduction. The Wärtsilä Slow Steaming Upgrade Kit provides us with a solution for further fuel savings, while maintaining the necessary full operational flexibility of the ships. The contract for the upgrade kits is an important decision for us.”

In addition to the fuel savings, this Wärtsilä solution provides full flexibility – with unrestricted operation from 10% to 100% load. The engine is not permanently derated, but retains full flexibility so that it can be operated at any time up to its full installed power for full sea speed. It also decreases the risk of engine fouling and excessive component temperatures. Installing the upgrade kit involves fitting shut-off valves in the engine’s exhaust duct before the turbocharger turbine, and in the scavenge air duct after the compressor. The valves are remotely operated by a control system included in the upgrade kit.