The performance upgrade on the Carnival Pride cruise ship improved the total economy of the vessel. The upgrade was part of a Performance Based Logistics (PBL) agreement between Wärtsilä and Carnival Corporation. “The upgrade resulted in fuel savings of 3% and is a good example of the good cooperation we have with Wärtsilä,” says Daniele Carbonera, Senior Manager Diesel Plants at Carnival Corporation’s Fleet Asset Management
The PBL agreement signed in 2017 focuses on improving engine performance and efficiency among other areas of interest. This upgrade was part of ongoing talks and focused mainly on utilising the latest technology to improve the performance of one of the six Wärtsilä 9L46 engines.
The Wärtsilä 46 performance upgrade included the installation of a new compressor wheel and a camshaft replacement to allow for Miller inlet timing. These new features increased efficiency over a wide range of engine operations, which was particularly noticeable in the reduction of thermal load, and improved turbocharger speed margin, and significant fuel savings.
Wärtsilä was able to show the effects of a performance upgrade on a Wärtsilä 46 engine. “We have gained savings in fuel consumption over the whole load range and for the optimised 75% load 6gr/kWh, which correspond to 3%. In addition, the improved combustion process will also improve the lifetime of the engine,” says Mr. Carbonera.
According to Mr. Carbonera, upgrades are planned and made in combination with other scheduled maintenance to minimise the time an engine is out of service. “However, if we test, for example, a prototype to establish if clear benefits can be achieved, we need to be able to separate these results from normal maintenance measures.”
Mr. Carbonera says that although the upgrades themselves are very smooth, the challenge comes from when they are mostly done during operations. “The work must be coordinated by the Service Operation of the vessel and according to engine availability requests. Thanks to the PBL agreement, Wärtsilä’s flexibility and the planned overhaul schedule, this is not a problem.”
A marine performance upgrade package comes with many improvements and benefits. Perhaps the most important issue is the increased efficiency, which results in reduced fuel costs. There is also a higher operational flexibility thanks to the improved turbocharger speed margin; and the reduced exhaust gas temperatures lower the thermal load, which leads to reduced maintenance costs. Moreover, everything is compliant with IMO regulations.
Besides the lower specific fuel oil consumption (SFOC) across the whole load range, Mr. Daniele Carbonera also highlights the importance of the PBL agreement. “The PBL provides mutual benefits for both Carnival and Wärtsilä through joint development work. Instead of just buying a new product, we now also get it installed and finetuned by Wärtsilä for optimal performance.”