You might not realise it, but quitting our addiction to oil means more than just finding something besides petrol to put in our cars. If we really want to stop using fossil fuels, we have to change the way we make roads — and cooking oil might just be the answer.
Over the past few months, Washington State University civil engineer Haifang Wen has figured out a way to make asphalt with used cooking oil, the same stuff restaurants throw out on a regular basis. While asphalt is traditionally made with the residue left behind after the production of petrol, plastics and other products, Wen's method is more affordable, better for the environment and petroleum-free.
"Building roads is a big investment in taxpayer money," Wen said in a statement. "In general, a one-mile road in a rural area costs at least a million dollars to build. With the waste cooking oil technology, we can reduce the cost of asphalt binder to under $US200 per ton, making road building much cheaper."
When you take into account the fact that the United States uses about 30 million tons of asphalt binder a year, that the savings from bringing the cost per ton under $US200 really adds up. This is just one idea for building better roads, though. Some scientists in Iowa have developed a way to make asphalt out of the leftovers of ethanol production, while some others in North Carolina can do it with pig manure. That's only the beginning too.
For Wen's method to make it into the mainstream, he'll have to prove that his cooking oil-based asphalt holds up just as well as petroleum-based asphalt. That will take time. In the short term, they will be experimenting with a short, 400m test road to be constructed later this year where Wen and his team can gauge the performance of their new asphalt.