Home' Ships and Shipping : January 2011 Contents Ready for the fuel of the future
Thoughts from the distinguished maritime commentator Michael Grey MBE.
Think of a couple of the worst problems facing ship operators
in the next ten years or so. The curbing of harmful emissions
comes high on the list, no matter what our stance might be on
Emission Control Areas, now established in the Baltic, North
Sea and now around North America, look certain to be extended to
such seas as the Mediterranean and Black Sea, and the Singapore
Straits. It would not be surprising to see Japan and even China
going the same way. We no longer make jokes about "the diesel
Then there is the growing clampdown on water ballast, as
governments act to prevent the transmission of alien species and
pathogens carried around in ballast tanks. The IMO Ballast
Convention might still have to come into force, but it is unlikely
to stop governments tightening up their regulations to prevent the
migration of these nasties.
Both of these issues are pressing, both will inevitably be
expensive to deal with and each carries a great deal of
environmental weight. The so-called sustainability of the shipping
industry and its perceived "green-ness" suffers if they are not
adequately dealt with, leaving the industry vulnerable.
So, what would your reaction be to a ship design that deals with
both these difficulties at a stroke? That hugely reduces harmful
atmospheric emissions, and at the same time eliminates the
carriage of any water ballast at all. It sounds quite fanciful, but the
new DNV "Triality" concept design for a VLCC does indeed fulfil
these criteria, employing a variety of technical solutions, all of
which are available today.
The design, which has been produced by a project team
assembled by the classification society specifically to undertake
the task, is based on an innovative ship fuelled by liquefied
natural gas, and with a hull configured to eliminate the need
for water ballast when operating in an empty condition. The
design provides for two pressurised tanks positioned on the
foredeck ahead of the superstructure, which between them will
provide for a range of 25,000 nautical miles. These will fuel two
dual-fuel slow speed main engines driving the twin screws,
along with the generators.
The "cooling" effect of the LNG will also be employed to cool
the scavenge air into the machinery and to condense the Volatile
Organic Compounds which are all recovered, rather than vented
into the atmosphere on the laden voyage, as they are at present.
Some 500 tonnes of VOCs will be recovered each voyage and
used productively to burn in the boilers to drive the cargo
pumps. The ship will emit some 34 percent less CO2, reduce
nitrous emissions by up to 90 percent and sulphur and
particulate emissions by 100 percent.
The design of the hull provides for a longer and wider body
and a "V" shaped cross section, which it is claimed will enable
the propellers to be well submerged with the ship light, and the
bow properly immersed. There is a substantially reduced wetted
surface with reduced resistance and more energy efficiency. The
internal design provides for four longitudinal bulkheads with five
cargo tanks in each of five sections provided by the six
athwartships bulkheads. And while this is a concept design for a
VLCC, it is suggested that many other types of tanker might see
the same benefits.
One might argue that this is ridiculously premature, pointing
out that there is no distribution system for LNG bunkers, and that
the only LNG fuelled ships are so far found based on Norway,
where a limited supply system is available. DNV's CEO Henrik
Madsen, however, believes that the growth in LNG production
points firmly to this ousting heavy oil as a bunker fuel in time,
with most owners ordering ships fuelled in such a fashion, perhaps
only ten years from now.
One might consider that the position of LNG as a maritime fuel
is not that different to that of coal some 150 years ago, when
shipowners were agonising whether to move from the free but
unreliable wind, to steamships. "But where is the coal to be
found?" they asked plaintively. But as soon as the demand was
identified, a distribution system was developed, and in
double-quick time. Arguably, LNG bunkering, which could be
undertaken by specialist bunker tankers, will be easier than lugging
hundreds of thousands of tonnes coal around the world.
This is a concept ship, and is far from a completed design, but
its purpose is to make people think constructively about which of
its ideas might be further developed. The name -- Triality -- shows
its three goals; its environmental superiority to today's ships, the
use of existing and well-proven technology and its financial
attractiveness, when compared to conventional ships operating on
heavy fuel, with all the increasing constraints and disadvantages.
Who might go for such a design? Perhaps an operator of shuttle
tankers, who is worried about the problems of operating in Emission
Control Zones will first embrace the concept. Or it could be that an
oil company anxious to reinforce its environmental credentials and
able to guarantee long term employment to and from an LNG
bunkering source will be the first to "bite". Or perhaps a big
independent, hoping to attract a reputable long-term charterer who
is vocal about its corporate social responsibility, could be a buyer
from a shipyard anxious to gain a technological lead.
One thing is for sure, environmental concerns won't go away,
and the ship operator able to point to a lead in this respect looks
certain to be a commercial winner. A ship design that deals,
simultaneously, with a whole tranche of worries that keep
operators awake at night is surely worth a closer look.
January 2011 SHIPS AND SHIPPING
An artist's illustration of the "Triality" design
Photo credit: © DNV/Making Waves
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