When I first heard the idea that the oil left behind in a restaurant deep fryer could end up powering a car, I thought it sounded like something someone says at a dinner party to sound interesting.
Then I started making calls. And it turns out it is not only real, it is already happening, quietly, at industrial scale, in Canada and beyond.
The person who explained it to me most clearly was Jared Girman, Director of Strategic Initiatives at West Coast Reduction, a waste organics company based in Vancouver, British Columbia. His job, in the simplest terms, is to find useful things to do with materials that other people throw away.
The Fatberg Problem Nobody Talks About
Before biofuel enters the picture, there is a more immediate problem worth understanding. A lot of used cooking oil ends up exactly where it should not: down the drain.
When that happens on a large enough scale, and it does, the oil solidifies inside sewer systems and combines with other waste to form what engineers grimly refer to as fatbergs. In December 2025, London discovered one weighing an estimated 100 tonnes blocking sewers in the east of the city. It was not the first time. A similar discovery in 2017 made international news. Both were preventable.
The solution Girman and his company pursue is intercepting that used oil before it reaches the sewers, cleaning it of impurities, leftover food particles, detergents, anything that ends up in a commercial fryer over time,and refining it to meet the precise specifications of petroleum refineries. Those refineries then blend a portion of the treated organic oil into their conventional crude oil feedstock. The result is a lower-carbon version of gasoline, diesel, or jet fuel.
It is literally from the deep fryer to your gas tank. That sentence sounds improbable. It is not.
Why Biofuels Count as Low-Carbon
The logic behind classifying biofuels as low-carbon took me a moment to fully absorb, but it makes sense once you sit with it.
The carbon in organic material, cooking oil, wood chips, crop residues, was already part of the natural carbon cycle before any of it entered a fryer or grew on a farm. When it is burned as a conventional fuel, yes, carbon dioxide is released. But unlike fossil fuels, where ancient carbon that has been locked underground for millions of years is released into the atmosphere for the first time, biofuels are recycling carbon that was already circulating. The primary use of cooking oil is frying food. Any secondary use as fuel is, from a carbon accounting perspective, a net-zero bonus.
This is why governments are willing to put serious money behind the market. In Canada, the carbon credit for biofuels was trading at around $375 per tonne of CO2 equivalent in late 2025. That price signal gives everyone along the supply chain, restaurants, collectors, processors, refineries, a financial reason to participate.
The Technical Reality of Cleaning Old Fry Oil
It sounds simple enough. Collect the oil, clean it, and send it to a refinery. But when I asked Girman what that cleaning process actually involves, I quickly realised the chemistry is not trivial.
Used cooking oil is roughly 45 to 50 percent oxygen by composition, according to Animesh Dutta, a mechanical engineer at the University of Guelph whom I also spoke with. That oxygen content has to be removed through a process called hydrogenation, which involves pumping hydrogen into the oil under controlled conditions. On top of that, there are impurities, fragments of food, cleaning products, anything that finds its way into a commercial fryer over a working week.
None of that can make it into the refined product that gets sent to a petroleum refinery. The specifications are strict, and every refinery has slightly different requirements. The traceability requirements are equally precise. The oil that leaves a facility like West Coast Reduction has to be fully documented, from the restaurant that produced it to the refinery that receives it.
Enter Pyrolysis Oil, And Its Significant Problems
Cooking oil is only one piece of the biofuel picture. At a research lab at the University of British Columbia, I spoke with Professor Tony Bi, whose team is working on a different type of biofuel altogether: pyrolysis oil.
Where cooking oil arrives in liquid form, pyrolysis oil starts as solid biomass — wood chips, agricultural residues, coconut shells, even plastic water bottles. The material is fed into a large reactor called a pyrolizer, which heats it at very high temperatures in a low-oxygen environment. Think of a barbecue sealed off from outside air. The intense heat breaks down the carbon chains in the biomass and produces a liquid that can theoretically be refined into transportation fuel.
The day I visited the UBC lab, the whole building smelled like a barbecue restaurant. That part, at least, I enjoyed.
The product itself is a different story. Mark Lefsrud, a bioresource engineering professor at McGill University, was blunt with me about the current state of pyrolysis oil. It is heavy, oxygen-dense, unstable, and generally low quality. Getting it to a standard that petroleum refineries will accept requires significant further processing that nobody has yet managed to do reliably at the scale refineries actually need.
How big a scale are we talking about? Lefsrud put it plainly: refineries are not interested unless you are producing in the hundreds of millions of tonnes. Most researchers producing pyrolysis oil consider 30 tonnes to be a meaningful output. The gap between those two numbers is the size of the current challenge.
Animal Fat Is Filling the Gap
Because used cooking oil alone cannot supply the volumes that refineries want, companies like West Coast Reduction have turned to another source: rendered animal fats.
The meatpacking industry produces significant quantities of animal byproducts, fats, oils, and proteins extracted from parts of the animal not used for food. These materials previously went largely to cosmetics and soap manufacturing. Increasingly, Girman told me, they go to renewable fuel production instead.
Beef tallow, specifically, has become a significant feedstock for low-carbon fuel manufacturing. Without it, he said, the volumes required to keep refineries interested simply would not exist, at least not in Canada, where deep-frying culture is less prevalent than in the United States and the geography makes collection over long distances prohibitively expensive.
The Honest Conclusion
I came away from these conversations with a cleaner picture of something I had vaguely understood before. Biofuels made from waste materials are real, they work, they are already reducing the carbon content of fuel being sold at pumps right now. The market is growing. The technology is improving. Researchers are making genuine progress on the harder problems.
But used cooking oil from restaurants is not going to replace crude oil. It is a piece of a much larger puzzle that also includes animal fats, agricultural residues, forestry waste, and eventually, if the chemistry gets solved at scale, pyrolysis oil from biomass and plastic waste.
The deeper truth I kept coming back to is simpler. Organic waste is not actually waste. It is a material with energy and value locked inside it, sitting in bins and drains and landfills every day, waiting for someone to build a supply chain around it.
The technology exists. The economics are getting there. What remains is the unglamorous work of building the infrastructure, finding enough feedstock, and making it cheaper to recycle than to throw away.
Every bag of fries cooked somewhere today is producing a small amount of oil with a second life waiting in it. Whether that life gets used is mostly a question of whether the market makes it worth someone's time to collect it.
Right now, increasingly, it does.