Valero Energy Corporation operates as an independent petroleum refining and marketing company. The company operates through three segments: Refining, Ethanol, and Retail. The Refining segment engages in refining, wholesale marketing, product supply and distribution, and transportation operations. It produces conventional gasoline, distillates, jet fuel, asphalt, petrochemicals, lubricants, and other refined products. This segment also offers conventional blendstock for oxygenate blending, reformulated gasoline blendstock for oxygenate blending, gasoline meeting the specifications of the California Air Resources Board (CARB), CARB diesel fuel, low-sulfur and ultra-low-sulfur diesel fuel. The Ethanol segment produces ethanol and distillers grains. The Retail segment sells transportation fuels at retail stores and unattended self-service cardlocks; convenience store merchandise and services in retail stores; and home heating oil to residential customers. Valero Energy Corporation markets its refined products through bulk and rack marketing network; and sells refined products through a network of approximately 6,800 retail and wholesale branded outlets under the Valero, Diamond Shamrock, Shamrock, Ultramar, Beacon, and Texaco names in the United States, Canada, the United Kingdom, Aruba, and Ireland. As of December 31, 2011, it owned 16 petroleum refineries with a combined throughput capacity of approximately 3.0 million barrels per day; and operated 10 ethanol plants with a combined nameplate production capacity of approximately 1.1 billion gallons per year. The company was formerly known as Valero Refining and Marketing Company and changed its name to Valero Energy Corporation in August 1997. Valero Energy Corporation was founded in 1955 and is based in San Antonio, Texas.