11.09.2012 -
There are major innovations on the horizon for maritime
transport, partly driven by the new international IMO regulations
which have imposed a drastic reduction in pollutants deriving from
marine propulsion, from 2015 onwards. One interesting solution
comes from Friuli Venezia Giulia, where, thanks to an industrial
research project co-funded by the ROP ERDF 2007-2013, a group of
businesses, universities and research centres have created a new,
"green" concept of liquified natural gas (LNG) for ships. The new
formula will completely eliminate the atmospheric emissions of
sulphur oxides and particulates, reducing CO2 and
nitrogen oxide emissions by 25% and 85%, respectively.
The research team, headed by Wärtsilä Italia and composed
of the Universities of Trieste and Udine, the AREA Science Park,
RINA Services, Cenergy, Navalprogetti and Energy Automation, has
set itself the task of tackling the double challenge now faced by
the industry. On the one hand, it has to cut the cost of refuelling
with traditional oil-based fuels, which may soon cost as much as
60% more, leading to an additional expense of $300 per tonne.
On the other hand, there is a need to protect the environment by
drastically reducing pollution levels from 2015, firstly in the ECA
(Emission Controlled Area) between the Baltic Sea and the coastline
of the USA, possibly extending as far as the Mediterranean and to
some of Asia's principal ports such as Singapore and Oceania - and
then in the rest of the world from 2020 onwards.
The project, baptised NGShiP, has resulted in studies being
carried out on initial feasibility, and on the cost effectiveness
of a using a liquified natural gas system on an average-sized
long-haul cargo ship. But why the choice of LNG?
"The use of LNG has undisputed benefits" - explains Rodolfo
Taccani from the University of Trieste - "both in terms of reducing
emissions and saving costs, considering that LNG has a lower cost
than traditional fuels, and that its price is likely to fall even
further". By combining the use of LNG with several innovative plant
engineering solutions designed to significantly improve energy
efficiency, NGShiP will be able to slash the costs of running a
ship by 40%, compared to the use of low-sulphur fuels.
The project's innovative concept requires the installation of an
independent storage tank to hold large quantities of LNG, the
absence of cryogenic compressors, which would push up the cost, and
in particular, full use of BOG (Boil Off Gas, the gaseous form of
methane naturally produced from stored LNG) to generate electricity
through the installation of fuel cells. This last solution would
meet the ship's energy requirements when navigating or in dock,
without the need for generators, cutting pollutant emissions even
further.
"Wärtsilä now has consolidated experience in building dual-fuel
(DF) gas engines" explains the engineer Yves Bui, NGShiP project
leader at Wärtsilä Italia S.p.A., "but we needed to work with a
team of highly qualified researchers in order to resolve the
various issues that could have impeded a wider use of LNG on cargo
ships with a storage tank. We have found that solution in Friuli
Venezia Giulia".
For the shipowner, the payback period for an installation of
this type is limited: a tanker ship of average capacity
(33,000 DWT) will repay the investment - including the system,
installation, maintenance and fuel - in 3-8 years (best and worst
case scenarios), depending on the cost of components and the trend
in the price of LNG compared to that of traditional fuel, used as a
benchmark. Thanks to a software program developed by the University
of Trieste, the project team can also recalculate the cost data to
reflect changes in the characteristics of individual parts of the
system.
This is not only possible for newly-constructed LNG ships, but
also for retrofits of existing ships. What's more, NGShiP has
demonstrated that using LNG even in non-ECA zones is usually
worthwhile, particularly for medium-sized ships transporting liquid
chemicals. During the life cycle of a LNG ship, estimated to be 20
years, the savings on running costs can amount to as much as Euro
70 million.
The project has now come full circle, thanks to a survey,
updated to 2012, of all the existing and planned port-based LNG
refuelling stations in Europe. Other potential sites on the busiest
maritime routes have also been identified. Installing large LNG
tanks on long-haul cargo ships is now possible, and is an
opportunity to make navigation more sustainable.