Gasoline's lowly status rose quickly after 1892, when Charles Duryea built the first U.S. gas-powered automobile. From then on, the light stuff from crude oil became the right stuff. Today, some refineries can turn more than half of every 42-gallon barrel of crude oil into gasoline. That's a remarkable technological improvement from 70 years ago, when only 11 gallons of gasoline could be produced. Essentially, refining breaks crude oil down into its various components, which then are selectively reconfigured into new products.
Employees regulate refinery operations from within highly automated control rooms.
Because so much activity happens out of sight, refineries are surprisingly quiet places. The only sound most visitors hear is the constant, low hum of heavy equipment. The complexity of this equipment varies from one refinery to the next. In general, the more sophisticated a refinery, the better its ability to upgrade crude oil into high-value products. The resulting liquids and vapors are discharged into distillation towers, the tall, narrow columns that give refineries their distinctive skylines.