Despite high prices at the pump, several U.S. oil refineries that make and sell gas are going broke.

Oil companies say the refineries are old and can't produce the cheaper and heavier oils made popular by suppliers in other countries.

They say about 50 percent of the refining capacity on the east coast are either closed or preparing to shut down in the coming months.

That may mean even higher fuel prices for drivers later this year if shortages develop.