What specific items can burn in a diesel vehicle that cost less than diesel fuel at the pump?

Bernie Cerra: Costs are dependent upon supply. Suppose you ran a string of deep fat fry eating places. You might be keenly interested in processing that used cooking oil to run in a diesel vehicle because the source would be an otherwise waste product for you. You would probably discover that processing oil rather than modifying the engine is likely to make the engine last longer with fewer problems. The same may be true if you had access to certain plants that could be pressed for oil, or if you were busy all day long cutting fat away from meat. On other side if diesel fuel were to suddenly rise in price many alternatives might suddenly become usable. People would start processing drain oil in their back yards instead of the already clean bio fuels....Show more

Rosalva Steinmann: Waste vegetable oil (you have to filter it) and homemade biodiesel are the only real cost-effective options. Kerosene will burn in a diesel engine, but it's more expensive right now! . You can buy vegetable oil for about $4 a gallon, so it's also more expensive than diesel fuel. For now.Another alternative is to fumigate natural gas or propane into the intake along with diesel/vegetable oil in the fuel tank. Natural gas costs about 1/3 as much as diesel, you can run up to 30% natural gas....Show more

Jerrod Guilfoil: Filtered waste oil.