Valero Energy Corporation is a Fortune 500 international manufacturer and marketer of transportation fuels, other petrochemical products, and power. It is headquartered in San Antonio, Texas, United States and was founded in 1983.
Throughout the United States and Canada, the company owns and operates 15 refineries, and one in Wales, with a combined throughput capacity of approximately 3 million barrels (480,000 m3) per day, 11 ethanol plants with a combined production capacity of 1.2 billion US gallons (4,500,000 m3) per year, and a 50-megawatt wind farm.
On August 1, 2011, Valero acquired the Pembroke Refinery from Chevron, as well as the marketing and logistics assets, for $730 million, excluding working capital, which was valued at approximately $1 billion.
The Pembroke plant is one of the largest and most complex refineries in Western Europe with a total throughput capacity of 270,000 barrels (43,000 m3) per day. This puts Valero at a total of 15 refineries and 2.9 million barrels (460,000 m3) per day of throughput capacity overall, solidifying the company’s standing as the world’s largest independent refinery.
According to en.wikipedia