Burning Used Cooking oil in Diesel Engines,
Rudoph Diesel's Vision Realized

Rudolph Diesel was a true revolutionary.  He believed that his diesel engine would revolutionize our world by allowing us to grow our own fuel.  Diesel engines can burn a variety of substances: thick and thin petroleum oils, plant oils, animal oils, flammable gases, and recycled waste products.  This is by far the most versatile combustion engine technology in the world.  Because of the low price of petroleum products at the turn of the 20th century, it was much cheaper to pump oil out of the ground than it was to grow it using the sun’s energy.  We are now at a turning point in history where petroleum products are becoming more expensive than used cooking oil.  For the first time since the inception of the diesel engine, we are finally starting to burn plant and animal oils directly in the diesel engine, just like our inspired inventor had originally envisioned.

How is a diesel engine different from a gasoline engine? 

The diesel engine uses a compression based explosion rather than an ignition based explosion.  This means that the molecules of fuel that enter a diesel engine are put under extreme heat and pressure, so much in fact that they literally just explode.  Gasoline engines uses a system of spark plugs to ignite the fuel in the engine.  In effect, gasoline engines can only burn flammable fuel sources such as unleaded fuel, natural gas, or alcohols.  Diesel engines are able to burn non-flammable fuel sources because of the compression-explosion in the cylinders.  Diesel fuel and vegetable oil are not flammable at room temperature and will not burn in a gasoline engine, but will combust in a diesel engine.