Not every oil company is enjoying windfall profits in the era of expensive oil.

Sunoco Inc., which refines oil it buys from producers, today reported a net loss of $59 million on sales of $12.8 billion for the first quarter of the year. Sunoco earned $175 million on sales of $9.3 billion in the first quarter of 2007. The 2007 figures included special items valued at $90 million, according to the Philadelphia Inquirer.

"The first-quarter market environment was clearly a challenging one for Sunoco and the refining industry," Sunoco chairman John Drosdick said in written statement.

The company lost $123 million in its core refining and supply business. Margins there were squeezed by the record-high prices for crude oil. Customer demand also fell, Drosdick said. But the company's retail-marketing business, its gas stations and convenience stores, posted a profit of $26 million for the quarter. That was largely due to higher margins, compared with the first quarter a year earlier, on gasoline and diesel sold at those outlets.

Sunoco's margin on a gallon of gas was about 11 cents in the first quarter of 2008, compared with 8 cents in the first quarter a year earlier.