There is a growing movement towards the use of renewable sources of energy. One viable option is using vegetable oil to run diesel-powered vehicles. Enthusiasts and purists prefer the use of waste vegetable oil (WVO) because it is the cheapest option and at the same time, it is a form of recycling. However, there are technical issues which must be considered before jumping into the bandwagon.
The diesel engine was originally designed to run on vegetable oil. But as the petroleum industry grew, diesel fuel became the standard by which future designs of the diesel engine was founded into. Since diesel fuel and vegetable oil have inherent differences in properties; all available solutions center on improving viscosity and combustibility of vegetable oil.
The easiest way to address the compatibility of vegetable oil with the diesel engine is through the use of additives or “cetane enhancers”. These commercial “secret formulas” basically address the main issue of making vegetable oil more efficient to run on diesel-powered engine.
Diesel Conversion Kits
Diesel conversion kits allow the use of both diesel fuel and vegetable oil through separate feeding tanks. The main principle is to use heated-up vegetable oil to fuel most of the running time and diesel fuel for certain critical periods.
Diesel conversion kits incorporate heat exchangers to raise the temperature of vegetable oil to 160-180 degrees Fahrenheit. The heating process makes the oil less viscous and more combustible. It for this reason that manufacturers, as a matter of operating protocol, recommend the use diesel fuel to start the engine, vegetable oil during cruising and shifting back to diesel fuel prior to engine stop.
Biodiesel is vegetable oil which has undergone through a process called transesterification. The process involves reacting vegetable oil with catalysts like methanol or ethanol and other reagents to remove free fatty acids. There are commercial modules available which also incorporates dewatering and filtration systems.
Finding a consistent source of WVO
WVO is usually free and can be source through restaurants and food chains. These outlets would be more than glad to have somebody pick-up their WVO on a regular basis. However, providing the vegetable oil source with collection bins is necessary to have an efficient collection system.
Deciding on the process and appropriate equipment
The minimum equipment needed for anybody planning to shift to vegetable oil, is a dewatering/filtration system. Dewatering involves heating the vegetable oil to remove water while filtration is needed to remove macro impurities. But for biodiesel production, additional equipments are needed for the transesterification process.
Finding a compatible vehicle
Vegetable oil can have adverse reactions on the different components of the fuel system. In many cases, it destroys major components of the engine. It is for this reason that proper consultation is needed before making a decision on which diesel-powered vehicle to buy.
As a matter of general principle, there are three vital components for any diesel-powered vehicle to efficiently run on vegetable oil: Indirect Injection System, Bosch Injection System and Heated Filtration System. However, newer models which have common rail and other types of electronic injection systems can run on quality processed biodiesel.