How much waste cooking oil?

Frying Chips

As of 2000, the US was producing in excess of 11 billion litres of WCO (Waste Cooking Oil) annually, mainly from industrial fryers in potato processing plants, snack food factories and fast food restaurants.

If all of those 11 billion litres could be collected and used to replace the energetically equivalent of petroleum, almost 1% of US mineral oil consumption could be offset.

Source: Wikipedia