What do you mean, you run on Veggie Oil?

Just that, our bus runs on used vegetable oil rather than diesel.

How do you do that?
You put veggie oil in the tank and then hit the gas pedal. Oh, you mean how do you get your vehicle to be able to run that way? First, you need a diesel engine. Then you need to get a conversion done on your vehicle. All diesel engines are able to run on grease, but the trick is to get the grease into the engine nice and clean and very hot. So the conversion does just that, it filters and heats the oil.