In the global trading market, the portion of shipping far exceeds that of any other trading methods. Despite the fact that shipping accounts for 80% of the world’s freight, it only consumes 2% of the world’s energy and has a carbon emission rate of only 3.3%. Thus, shipping is not only very efficient but also eco-friendly.
For better environment and sustainability, today’s trend of increasing restriction of carbon emission and demanding more eco-friendly approach have become inevitable in the shipping industry. For example, nitrogen oxide and sulfur dioxide emission rates have already been reduced 5 to 20% of current rate since the introduction of MAPOL’s regulation. In 2011, IMO has decided to implement EEDI(Energy Efficiency Design Index) which requires reduction of greenhouse gas emission to 30% of current rate to all newly built ships over the course of 12 years, starting from 2013. Since most current ships rely on bunker fuel which releases a lot of greenhouse gas, they require either nitrogen oxide reduction catalyst, desulfurization equipment, or high-priced low sulfuric fuel in order to meet the new MAPOL’s regulation. However, because these methods increase the cost of building and operation, utilization of LNG(Liquefied Natural Gas) as a fuel source has gained attention as an emerging solution recently.
LNG as fuel is not a new invention though today LNG is used as main propulsion fuel for some Norwegian ferries and offshore vessels. The bunkering is done by truck or directly from a shore based terminal, a proven technology that works well in Norway. This is not an alternative for larger ships though, where the LNG volumes are too large and the supply from a tanker truck would be too time-consuming.
A build-up of an LNG supply chain based on ship to ship bunkering instead is therefore of significant importance for LNG to become a real alternative to Heavy Fuel oil and other bunker fuels. Nevertheless, there are no existing international guidelines for the procedure of ship to ship bunkering of LNG have not been established up to date.
This paper aims at establishing a Green Ship design for the LNG fuelled vessels and encompassing the entire bunkering operation.