Advances in exploration and production have helped to locate and recover a supply of oil and natural gas from major reserves across the globe. At the same time, demand for petroleum-based products has grown in every corner of the world. But supply and demand are rarely concentrated in the same place. Transportation therefore is vital to ensuring the reliable and affordable flow of petroleum we all count on to fuel our cars, heat our homes and improve the quality of our lives.
Tankers and pipelines are proven, efficient and economical means of connecting petroleum supply and demand. Supply-end pipelines carry crude oil from well to a loading terminal at a port. Tankers then carry the crude oil directly to demand-side pipelines that connect to the refineries that convert the raw material into useful products. Select the dates at left to see how the shipping of crude oil has evolved over time into the high-tech, reliable and environmentally sound system we enjoy today.
1885 - The United States and Russia were the major producers of crude oil, most of which was refined into kerosene. Invented in 1854, kerosene was in demand because it burned cleaner and brighter than other lamp fuels, such as whale oil. Kerosene from American refineries was soon crossing the Atlantic to meet growing demand in Europe.
The first oil exports crossed the ocean aboard all-purpose sailing ships, stored in the same wooden barrels usually used for wine.
Some of these ships were later outfitted with large-volume tanks to increase their carrying capacity.
Eventually, ships were built specifically to carry oil and petroleum products. The Glückauf, launched in 1886 and featuring an extra-strong hull, reinforced construction and specialized oil-handling systems, is considered the forerunner of modern oil tankers.
1955 - The automobile revolutionized American life in the first half of the 20th Century and created increased demand for gasoline. Oil also helped power rebuilding efforts after two destructive world wars. To ensure adequate supply to meet the growing demand, exploration and recovery efforts focused on new sources in the Middle East and Canada.
The need to deliver more oil called for larger tankers. Early iron and steel vessels were built using the same principles as wooden sailing ships -- lateral framing pieces attached to a single keel -- but problems with weight distribution and structural rigidity limited tankers to 82,000-barrel capacity. In 1908, Sir Joseph Isherwood patented a new shipbuilding technique that included frames and bulkheads running front-to-back and used the ship's floors to increase rigidity. By the early 1950's, "supertankers" built using a modified version of Isherwood's system had capacities of more than 280,000 barrels.
2002 - In the latter half of the 20th Century, advances in exploration and recovery technology opened up new supplies of oil and natural gas all around the world. To make long-distance transportation more cost-effective, tanker manufacturers developed "very large capacity carriers," or VLCCs, that can carry more than 1,400,000 barrels of crude oil.
Larger tankers conserve energy and reduce transportation costs. That's because although it requires more energy to power a larger ship, the rate of increase is less than the rate of increase in carrying capacity. For example, 16,000 horsepower are needed to drive a 420,000-barrel tanker, while 42,500 horsepower can propel a 1,820,000-barrel ship at the same speed. That means it takes less than three times the power to deliver more than four times the oil, reducing total energy consumption and saving fuel.»next