International shipping company, Clipper Group, says it has achieved an overall fuel savings of about 8.5% from a new bulbous bow recently installed on a 2011-built multipurpose vessel.
Clipper says that an in-house technical management team decided on a new bulbous bow while working on fuel efficiency and energy consumption optimization.
The company says that often times bulbous bows can actually have an adverse effect on efficiency since they are often developed for full speed and close to full load conditions, when in reality most vessels are operated at eco-speed in part load conditions. Clipper says this is particularly true of multipurpose vessels, which are seldom operated in full load conditions.
The bulb of Clipper Galaxy was modified during dry-dock at Lixin Shipyard in Shanghai in August 2013, where the existing bulb was cut off and replace with a new bulb of a different size and shape. At the same time, Clipper also designed and fitted a rudder bulb improving propeller efficiency by 2-3%.
Clipper says that the savings of the bulb modification alone would be above 10%, but with trim optimization and considering factors such as loading and speed patterns, the overall saving is around 8.5% – including the rudder bulb effect.
Clipper Group manages and operates about 175 vessels in total across the bulk, tankers, cruise vessels, ferry and ro-ro segments.
TYPE: Multipurpose/tween/container/heavy lift
GRAIN/BALE CUBIC: 11,131 / 370725 cubic feet
HOLDS/HATCHES: 1 HOLD/1 HATCH
CRANES: 2 X 200 MT – COMBI
SPEED/CONS: 14 KNOTS ON 17MT IFO 380CST