All-LNG power plant
What sets ESL Shipping’s new extremely energy-efficient bulk carriers apart from most LNG-fueled ships is that in addition to main engines, both auxiliary engines and boiler are powered by LNG. This setup enables further reduction in CO2-emissions. Pure LNG power plant means that LNG can be used as a fuel even in ports as auxiliary engines use LNG as well. In many LNG-powered ships auxiliary engines run with marine gas oil meaning that ship’s emissions at port are higher than at sea compared to completely LNG-powered ships.
The low-speed, two-stroke main engine is supplied by MAN B&W and it has a power of 6000 kW. The operational principle of MAN engine is based on diesel process meaning that the high pressure gas is injected to a cylinder after the ignition with the pilot fuel. This enables minimal methane slip which is extremely important factor as the global warming potential of methane is 25 times higher than that of carbon dioxide.
In addition to main engine output of 6000 kW, extra 1250 kW can be generated through shaft generator, powered by three MAN 23/30 auxiliary engines. This extra power is mainly needed to achieve the requirements of Finnish-Swedish ice class 1A. The gas system including gas tank and piping is provided by Gloryholder Liquified Gas Machinery.
The gas tank has a volume of approximately 400 cubic meters enabling operational autonomy of 14 days. Challenge in the LNG is that gas tank can be neither almost empty nor full. There must always be around 100 cubic meters gas and the tank can be filled up to 300-350 cubic meters.
Supply of liquefied natural gas for newbuildings is based on industrial gas storages at the factory sites as the supply of liquefied natural gas in commercial ports is currently insufficient. Due to the lack of bunkering facilities, the bunkering of the vessels will take place by trucks.