Trucks, heavy generators, trains, large buses—you can mention them. What do all these have in common? They are heavy. And they make use of diesel. This leads us to the main topic: Why diesel?
First, to understand this, we have to understand what is actually different between regular petrol and diesel. The difference lies in their chemical composition and the way they are refined. Remember back in your organic chemistry class, where it seemed like what you were taught was passing into one ear and leaving the other? Well, let me make this simpler for you to understand, so the past doesn’t repeat itself.
Petrol is lighter and more volatile, which means it evaporates more easily. It is derived from crude oil, as we all know, through a refining process called distillation, resulting in a fuel that ignites quickly under pressure. Diesel, on the other hand—let's say it's a heavier fuel that contains more energy per gallon. Compared to petrol, it evaporates more slowly and is denser, making it less flammable and better suited for engines that require more power over time, whether driving long distances or carrying a heavy load. We'll soon get to the part about why petrol can’t be used instead, but for now, stick with me.
