The early aughts in Los Angeles were a time of trucker hats, skinny ties and white belts, vintage T-shirts, and the rise of young Hollywood’s convergence with reality television. They also heralded the epoch of french fry-scented exhaust fumes wafting through trendy neighborhoods like Silver Lake, Echo Park, and Los Feliz. That’s because various environmentally conscious residents of those areas were converting their diesel cars and trucks to run on vegetable oil. Companies sold kits that allowed vehicles to be converted within hours.

One of the most significant benefits of using recycled cooking oil to fuel cars is the overwhelming prevalence of the product. There is no shortage of fast-food restaurants looking for ways to discard their vats of used oil. Drivers can easily negotiate prices for this fuel. Vegetable oil is also a perfect way to limit one’s carbon footprint by lessening fossil fuel usage considerably. The only thing needed is a vehicle that runs on traditional diesel. With rising fuel costs, supply chain issues, and an executive order to phase out gasoline-powered cars by 2035, cooking oil and biofuels, in general, are exciting territory.

Robert Tomey, an Alabama-based fast-food franchise owner, proudly used the more than 10,000 gallons of grease from his businesses to fuel his car. NBC News reported Tomey’s story back in 2006: “The engine runs cooler,” he said. “I think it’s because the flash point — the ignition point — of that grease is lower than the diesel fuel.” Tomey’s implementation of biofuel technology might have been unique in the United States, but around the world, it’s becoming more and more common. In 2015, it was announced that Dubai became the first city in the world to run 100% of its fleet of municipal vehicles on biodiesel made from recycled cooking oil.

While cooking oil makes for an audacious fuel alternative and a sterling conversation starter, this innovation has a few issues. There were wranglings with the Environmental Protection Agency, which had banned the use of veggie-oil cars because accurate levels of pollution hadn’t been determined. That was a challenging issue for California drivers already subjected to stringent emissions regulations. To date, this is still a concern. Next, the oil has to be warmed before the driver can use it in a converted vehicle because viscosity has a direct effect on the engine’s performance. While people with contemporary vehicles can just get in and go, veggie cars require additional finessing. Furthermore, there is the high cost of fuel taxes that environmentally conscious consumers may not have considered. Having an improperly registered car that runs on vegetable oil can take away from all the cost-effectiveness of these sustainability measures.

Owning a vegetable oil-converted vehicle, in theory, is a great idea. It is clever to take a used food item and repurpose it for a second life as an energy source. Traditionally frowned-upon gas guzzlers like pick-up trucks could become as cherished as the Prius or Tesla. With so many people struggling to pay gas prices and companies marking up products to offset the cost of refueling their fleets, this idea deserves a second look. Even if vegetable oil is permanently ruled out as a safe and healthy alternative for this planet, pivoting to biofuels and electricity will continue to be an environmental saving grace.

Sources: World Economic Forum, Mother Earth News, NBC News