According to the EPA, 28% of greenhouse gas emissions come from transportation. Every car on the road contributes to global warming by burning carbon that has been trapped underground for millions of years and adding it to the air. Barring buying an electric car, biking, and taking the bus more often, how can you cut down on the carbon emissions of your individual transportation? One option is to make the switch to biofuels. A biofuel is any fuel derived directly from living matter. Two of the most popular biofuel options available to individual consumers are biodiesel and waste vegetable oil (WVO). If you want to make the switch, how do you determine which is right for you?
Any car that uses biodiesel or WVO will have a diesel engine. According to Auto Auction Mall, the largest online marketplace offering used cars for sale, diesel cars have more power, and have experienced an uptick of popularity with consumers as cleaner, quieter models have come on the market. You can run a diesel engine on cooking oil—just like you would buy at the grocery store—with no major changes, and that is the essence of switching over to WVO. It is an appealing notion: restaurants will give you used cooking oil for free. You would have to filter it, of course, but you would never have to pay for a tank of gas again. However, just like the bottle of vegetable oil in your cabinet, the vegetable oil in your car will become murky and thick if it gets too cold. That’s why companies like Greasecar offer tank warmers; your car won’t run with a tank full of coagulated grease. Biodiesel fuel circumnavigate this problem by cutting the fuel with petrol diesel fuel.
Refining biodiesel is similar to refining normal oil products, as this chart from SeQuential biodiesel demonstrates. The processor collects used biological oils, filters them, then refines the product into biodiesel. Biodiesel is greener than normal diesel because it burns carbon that is already part of the current carbon cycle. Rather than taking burning carbon that has been trapped underground for millions of years, it burns carbon from plants that grew only last season. Because biodiesel is made from plants, biodiesel is a renewable resource, unlike petroleum.
Compared to switching to biodiesel, converting a car to run off of cooking oil will take more work, and it will take upfront investment. You will also have to worry about filtering the cooking oil yourself. None of these steps are impossible, but you have to consider the value of your own time against the amount of money that you will save from free gasoline. It is a value that is achieved more often with economies of scale—for example, a stadium converting its utility vehicles to run off of the grease from its fryers—than individual consumption. Though biodiesel is not nearly as universal as normal diesel fuel, there are online databases that allow you to search for the closest gas station that services biodiesel.
Most cars come ready to run off of biodiesel, though TechCrunchTechCrunch notes that biodiesel will rot rubber hosing and seals. If you are running biodiesel in an older car, you should ask your mechanic if your car uses rubber or synthetic. Biodiesel will also clear out the junk and buildup in your engine, meaning that you will probably have to replace your fuel filters several times while your burn your first tanks. However, the fact that Biodiesel is a solvent (meaning it dissolves other substances) also means to your engine will have a longer lifespan.
