Many countries are becoming concerned over the limited availability of petrochemical diesel fuel or their forced reliance on the countries that sell it. The solutions they came up with range from increasing the engineering to look for more oil at home to moving away from petrochemicals altogether. There exists a non-petrochemical based diesel fuel, known as biodiesel, that is becoming increasingly popular among developed countries. To learn more about biodiesel, about where it comes from and what applications it can be used for, consult this guide.
Biodiesel gets its name from the fact that it is biologically based rather than derived from petrochemicals (i.e. oil). It's a modified form of vegetable oil or animal fat mixed with alcohol. The technical term for biodiesel, which you will run into if you're working on a research paper, is transesterified lipids. Biodiesel is a specially engineered substance that can stand in for regular diesel, and should not be confused with the waste oils that are also sometimes used to run engines.
The difference between waste oils and biodiesel is that biodiesel is designed to be used in regular diesel engines without having to modify them. If you put biodiesel in your truck it would run, but if you put waste oil in your truck it would ruin the engine, turning it into nothing more than a huge lump of ballast lead. If you have a truck full of restoration materials, the last thing you want is a broken down truck while customers are left waiting. Most biodiesels aren't pure biodiesel - they're a mixture of biodiesel and petrochemical diesel. Commonly sold mixtures are B2, B5, B20, and B100, where the number after the letter B denotes what percentage of the mixture is biodiesel.
Though biodiesel is designed to run in unmodified diesel engines, there are certain maintenance problems using biodiesel may cause. Older engines often still have rubber parts which will be slowly eroded away by biodiesel and need to be replaced. This is mostly a problem with engines made before 1992 and can be solved by replacing rubber parts with FKM. Biodiesel also breaks down deposits left by petrochemical diesel in engines, which can clog filters after the transition is made.
Biodiesel is becoming increasingly widely available, as it is used in trains, furnaces, cars, and buses. There are several companies that are already selling it and the Chrysler company is designing cars to work with it. There are some concerns about biodiesels using up rapeseed and soybean matter that should be used for food, but biodiesel can also be made from waste vegetable oil, animal fat that is a byproduct of the meat industry, and farmed ocean algae. Using biodiesel results in a 50-80% reduction in greenhouse gas emissions.