LNG (Liquid Natural Gas) comes from fossil energy just like oil. To transport this gas so we need to reduce the volume of its gas. To reduce the gas we need to reduce the temperature to so the gas will change to liquid.As we know the moss spherical LNG tank is separate with the body of the ship, so there are space between the body and the tank. The space between LNG tank and the body of the ship mostly fill with inert gas so if there are any leak from the LNG tank the gas cant be burn because there are only some of Oxygen left.On the LNG ship we use stainless steel material for the pipeline. Its because with stainless steel can absorb force although the material on the low temperature condition. Otherwise, The steel cant handle the force if the material on the low temperature condition, if we use steel on the low temperature condition it can be broken.Just like tanker who carry liquid cargo, there must be sloshing effect in the tank. So on the LNG ship we use moss spherical LNG tank to reduce sloshing effect. Because the area above the liquid surface will be reduce. Than LNG vessel didnt use ballast water to stabilize the ship after the unloading process, LNG vessel use its cargo to stabilize the ship. So when the unloading process, not all the cargo move to the bunker, some LNG that left in the tank will be used for stabilize the ship it self.For the fuel its self LNG vessel use their own cargo. So when there are any gas that release from the tank it can be use to boil the water on the boiler, than the boiler produce steam and steam produce energy to make the engine works.