Home' Work Boat World : November 2015 Contents In recent months there has been a veritable rash of
LNG-powered tug deliveries in the Far East. It started in July
when the stra ngely-named ‘Offshore Oil 525’ wa s delive red
by a Chinese yard to CNOOC for operations at their Haina n
Yangpu terminal. She was followed one month later by, wait
for it, ‘Offshore Oil 526’ .
These are believed to be the first pure LNG-powered ASD
tugs in Asia, and would seem to result from a decision by the
Chinese government in 2011 to strengthen its maritime sector
by manufacturing high-end and ecologically efficient ships
The tugs are equipped with Rolls Royce engines and thrusters,
and the manufacturers claim they will reduce CO2 emissions by 25
per cent and NOx emissions by 90 per cent. SOx and particulate
emissions will also be “removed”, although the extent of that
removal is not specified.
The vessels are reasonably photogenic, and actually look like tugs.
Barely one month later, NYK Line in Japan took delivery of
‘Sakigake’, a dual-fuel tug capable of running on LNG or heavy oil.
She will be operated by the highly-regarded Wing Maritime
Services Corporation in Yokohama and Kawasaki ports. I do not
understand the reason for mixing LNG with heavy fuel – to a
layman, the good of one would seem to be eliminated by the
nastiness of the other – but let us hope the vessel will use a lot
more of the good stuff.
The Japanese tend to be cautious with new technology, and
they have said that ‘Sakigake’ will be used to “verify the
effectiveness of LNG as a marine fuel”, which sounds sensible.
Visually, the tug will appeal to traditionalists, since it appears to be
the standard Japanese harbour tug design which has been in use
since the 1970s.
It will be interesting to see how these new tugs perform, and
whether they will herald a surge of orders for environmentally-
friendly tugs in Asian ports. In the meantime, I was happy to
bask in a warm and fuzzy feeling because the Far East has
inserted itself into the forefront of the race to a cleaner future
for the towage industry.
The warm and fuzzy feeling lasted for about a week, until I
came across the work of Germany’s Nature and Biodiversity
Conservation Union (NABU), which is fairly critical of almost
everything to do with ships. For example, they praise only two
cruise ship operators (the ones which have ordered LNG-powered
passenger vessels) and accuse the rest of “hanging on to” the use of
HFO and investing in emission abatement techniques only if
forced by law to do so.
They also say all ports should have shore power facilities, with
the power coming from renewable sources. Easy enough to say, of
course, if not completely practical. Being based in Germany, with
lots of mountains and a constant freezing gale blowing in fro m
Siberia, it is probably hard to picture Singapore with its light airs
and featureless terrain, but they might have tried.
They are equally scathing about European efforts to limit fuels
to a sulphur content of 0.1 per cent, pointing out that this is still
100 times dirtier than the diesel used in road transport. They seem
to igno re the efforts that went into mandating this low-s ulphur
fuel for ships in port, and there is no mention of how much better
it is than the fuels which were used in the past.
If NABU come across as being slightly unworldly, there is no
doubting their dedication to the environment, and they have
published some interesting studies, including the recent Clean Air
in Ports. This voluminous work is too complex to summarise, but
the comments about LNG are worth considering.
After pointing out that LNG can reduce SOx and particulate
emissions by up to 99 per cent, NOx by 80 per cent and CO2 by 20
per cent for some ships, they then remind us that LNG must be
stored and transported at -162 degrees, which requires a lot of
energy. The production of LNG also generates methane, which is
25 times more harmful than CO2 in terms of climate change.
NABU claims that LNG fuel can actually do more damage to the
environment than HFO if it is not produced and stored using the
very best practices. Even if best practices are employed throughout
LNG offers, at best, an 18 per cent reduction in greenhouse gases
compared to HFO.
Harbour tugs, of course, tend to burn marine gasoil and not
HFO, so I have no idea how beneficial the switch to LNG could be.
There might be a 10 per cent reduction in greenhouse gases, but
many operators could do better than that by slow steaming
between jobs and paying a bit more attention to scheduling.
Years ago in Hong Kong we decided not to ask the tugs to
return to base between jobs, but kept them around the terminals to
reduce steaming times. We also capped their speeds except in
emergencies and used a tracking system to help us choose the best
and most efficient utilisation. These tactics reduced our fuel
consumption dramatically, so we felt we were doing our bit for the
environment. It also saved the company money, which was nice.
LNG-powered tugs are not likely to save anybody money, and it
seems their only benefit is to the environment. Thus we need to
know exactly how beneficial they are going to be. Most tug people
live around the ports they serve, and will be delighted if they can
reduce the pollution suffered by their friends and family, but
owners are not going to invest in cleaner technology without good
reason. Perhaps the greatest service the owners of the new LNG
tugs can perform is to collect and publish real data to convince the
rest of us to follow suit.
With ALAN LOYND
The East is Green
‘Offshore Oil 526’
10 November 2015 WORK BOAT WORLD
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