Tesoro Corp. on Monday agreed to buy BP PLC’s oil refinery in Carson and 800 gasoline stations in the Southwest for $1.18 billion.

Bloomberg News reports that the deal enables the San Antonio company to expand on the the West Coast just as a fire at a San Francisco Bay Area-area plant has cut fuel supplies and boosted prices.

The Carson plant, which will be Tesoro’s third plant in California, is next to the company’s Wilmington refinery. The company expectsfit can save $250 million a year by combining the plants’ operations.