The Big Pinch: Oil Prices, Fuel, and International Shipping

Posted : 12/24/12 11:25 AM

Oil has been the fuel of choice for powering ships for over a century now, supplanting coal as a source for running steam boilers just as diesel engines have largely replaced steam engines. The grade used is commonly called bunker fuel and can quite literally be termed bottom of the barrel, since it is the densest form of liquid found in petroleum and tends to sink to the lowest levels during the refining process known as cracking. The term bunker refers to the containers used to store the oil aboard ships. Increasing fuel costs have led to greater attention being given to fuel management systems and advances in technology have permitted greater oversight to be possible. Bunkers are now equipped with sensors that continually monitor fuel use and allow the crew to make decisions on engine speed and course corrections that will impact fuel usage rates. These instruments also allow authorities to closely monitor any spillage that might occur. The system has greatly reduced loss and pollution that used to result from overfilling tanks and has also cut down on pilferage. Ship exhausts constitute a significant source of global totals for emission of both nitrogen oxides and sulfur oxides, two troublesome pollutants. The sulfur content in bunker fuel tends to be high, giving port cities major problems regarding air quality and health considering the adverse effects sulphur has on respiratory systems, particularly of the very young and the very old. To combat this, many ports have installed stationary power sources that ships can plug into when docked. This eliminates the need for ships to keep their engines running while in port, while keeping with all of the electrical systems that ships employ. Manufacturers of ship engines continue to work on making their engines run more efficiently in order to lower fuel usage. Rising petroleum prices demand that they continue to do so. Regulating throttle speed is the primary means the crew can employ for saving fuel when the ship is in motion. Wind and currents can significantly alter fuel consumption so captains will attempt to set a course that permits the least impediment to travel. This has been aided by advances in communications that allow for greater monitoring of weather conditions, along with GPS devices that track the exact location of the vessel. All the information can be cataloged on a computer that analyzes the data and determines the exact rpm rate that will provide the highest level of fuel economy.