Ten Maersk ships are getting a new bulbous bow in order to make them more fuel efficient. The change is intended to improve the performance of the vessels significantly, with fuel costs reduced by approximately 8% in the current slow-steaming environment. The vessels were too expensive to use, since they were designed for high speed. If they were retrofitted, however, Seago Line were interested in taking five vessels.
Maersk Maritime Technology found that the bulbous hull form, initially developed to even out the waves created alongside the vessel and thus reduce the power requirement, is incompatible with initiatives to improve energy efficiency. More specifically five out of the seven ships in the Boston class will operate at a lower speed than the one they were designed for. At such low speed, the current design of the bulbous bow is not optimal, and therefore it was decided to investigate if something could be done to improve the fuel economy of the ships.
Initially, one approach was to trim the ship so that the bulbous bow gets submerged since tests by Maersk Maritime Technology Hydrodynamics had shown that this can positively impact ships’ fuel efficiency. But for one thing there can be obstacles such as load and weather conditions making trimming impossible, and for the other, this would not increase fuel efficiency sufficiently. It was decided that something more drastic was required to bring these ships back on track and the radical idea was born in Maersk Maritime Technology Naval Architecture to replace the entire bulbous bow (200 tons of steel) with one that is adjusted to the ships’ actual speed profile.
Four of these vessels had their new bulbous bow installed in Qingdao, China, and have now been delivered to Seago Line. But the last one proved a bigger challenge, as it was lying idle in Europe. The cost of bringing the Maersk Brownsville to Asia was too high, but so were the quotes offered by European yards for the operation.
Some rough figures helped justify the operation. Manufacturing the bulbous bow in Europe would cost $2.34 million compared to $470,000 in China. Transporting the 200 tonne bow from China would cost $550,000 on a bulk carrier, whereas installing it in Europe would cost $910,000. From this the case for shipping it from Asia to Europe, but using a Maersk Line vessel instead of a bulk carrier would mean even further savings, with amounting to total expected savings of $960,000. The nose was shipped in five parts – on one of the previously retrofitted vessels, the Baltimore (now Seago Felixstowe), for Europe. The Maersk Brownsville was expected to be ready with its new energy-efficient bulbous bow on 8 February, tol enter service as the Seago Piraeus.
Sources: Maersk Line Social, Maersk Maritime Technology
Officer of the Watch 
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