13 Mar 2014
The use of liquefied natural gas (LNG) as a potential replacement for conventional bunker fuels has become an increasingly discussed topic within the shipping industry.
"LNG as a fuel offers obvious environmental benefits," said Remi Eriksen, executive vice president at classification society Det Norske Veritas (DNV), in May.
Compared to the high sulphur residual fuels most widely used at present, LNG is said to reduce carbon dioxide (CO2) emissions by around 20%, nitrogen oxides (NOx) by 85-90%, and give a near 100% reduction in sulphur oxides (SOx) and particle emissions.
DNV has said there are "three main solutions" for emission control areas (ECAs) compliance after 2015 when the sulphur limit falls to 0.10%; low sulphur fuel, scrubbers for exhaust gas purification or the ship can be fuelled by LNG.
LNG can meet the most stringent emission standards, including Tier III NOx limits and SOx requirements in ECAs, without any treatment of the exhaust gas.
DNV said that LNG was "the preferred alternative" because it is "often more economical than the alternatives" and an "environmental winner".
"LNG as fuel is now a mature technology representing no technical obstacles," DNV said.
Global operations will be subject to a 0.50% sulphur limit from 2020 or 2025 which will likely call for the use scrubbers to be able to continue operations with residual fuels, or a switch to lower sulphur distillates or other types of fuel.
DNV's CEO Henrik O. Madsen recently said he was baffled the shipping industry has been so slow to use LNG as a bunker fuel.
“At times I have found it difficult to understand why the shipping industry has not switched to LNG – given the great commercial and environmental advantages,” said Madsen.
While LNG has many merits, there are also challenges which the shipping sector - just out of a recession - has to confront.
Dorthe Jacobsen of MAN Diesel said in April that LNG tanks will need to be around two-and-a-half times the size of a traditional fuel tank to give a ship adequate steaming time between refuelling stops.
LNG's potential have also been limited by an "immature LNG market" as well as a lack of "any form of usable supply chain for distributing the fuel".
Several companies in the shipping industry, meanwhile, have revealed plans to develop gas-fuelled merchant ships.
Wartsila in March signed an agreement with South Korean shipbuilder Samsung Heavy Industries (SHI) to jointly develop next-generation ships that run on LNG.
"A fundamental solution to satisfy regulations is to develop a liquefied natural gas-fuelled vessel instead of Bunker-C oil," said SHI Vice President Lee Kyo-sung.
European ferry company Scandlines GmbH announced plans in March to put two new ferries into service that will allow for adaptation to LNG as bunker fuel.
Norwegian ferry operator Fjord1 in June signed a contract with Fisker Strand BLRT AS for the design and construction of what is being claimed as the world's largest gas-fuelled ferry.
In China, US listed China Natural Gas, Inc. reported successful tests of the first LNG-powered ship with hybrid power technology in Chinese waters.
"This latest success proves that advanced dual-fuel hybrid power technology for ships is an economical, reliable, and energy-saving environmental technology," said Qinan Ji Chairman of the Board and CEO of China Natural Gas.
A recent article on BIMCO’s website by ‘the Watchkeeper’ said the arguments against LNG "are being gradually demolished by technology, environmental pressures and economics".
The bunker fuel industry has already discussed a move away from residual fuels to distillates as the main bunker fuel to meet increasingly stringent regional and global emission limits.
With growing interest in LNG, the latest Bunkerworld Poll asks:
Rammads Mohammed; PhD