Imagine driving from Halifax to Vancouver on $5 of gas. Yes, we’re talking covering 6,200 kilometres, the width of our continent, on less than five litres of fuel.
Futuristic fantasy? Nope. Students from the University of Toronto’s Supermileage (UTSM) Team have created a vehicle that can do just that.
Their car is roughly 65 times more fuel-efficient than a Toyota Prius. While the Toyota burns 4.5 litres of gas per 100 km, the students’ car burns just 0.069 L/100 km, or about 3,400 mpg US. And it’s not even a hybrid.
“It’s supposed to be quite a bit better this year, but I’m not going to say a number in case I’m off,” says Mengqi Wang, pictured above, left, a team leader and PhD candidate in electrical engineering.
“We like to set high expectations,” adds Kristine Confalone, pictured above, also a team leader and fourth-year undergrad in chemical engineering.
They, along with a team of fewer than a dozen students, built this Supermileage car from the ground up to take part in the annual Shell Eco-marathon, a competition that sees students vie to design and build the most energy-efficient vehicle.
More than 1,000 students from universities all over the world compete in one of three events in either the Americas, Europe or Asia.
The UTSM workshop is in downtown Toronto, inside one of the many brick buildings on the sprawling U of T campus. Inside a large room are what look like two missiles, or perhaps unusually aerodynamic coffins.
Mengqi Wang pops her head up from behind one of the missiles to say hello, and then gets back to work assembling a new rear wheel. The hub is a work of mechanical engineering art created by the team, with the smoothest, most perfect ball bearings.
Wang and Confalone demonstrate, by giving the wheel a little spin. Near-frictionless, it doesn’t stop, and just keeps spinning. I get bored watching it before it even starts to slow down.
The workshop is shockingly clean, especially considering they share it with other students building airplanes and drones and all sorts of other cool things they don’t let you do when you get a liberal arts degree.
Wang and Confalone walk me around the two cars. One is gas-powered, the other, newer one is electric. “The vehicle is 74 pounds,” they spout. “You can grab the five-point harness [seatbelt] and lift the entire car with the driver in it.”
“We use just over six millilitres [of gas] for a run of approximately 10 km,” they add.
“The aero-body [outer skin] is carbon-fibre, two millimetres thick. We reinforce strategic places using carbon-fibre tubes with foam inside.”
UTSM is the only team to have built its own gasoline engine, from scratch. It powers the single rear wheel via bicycle chain. Even the rear sprocket is carbon.
(photo courtesy UTSM)
An ingenious clutch allows the motor to completely detach from the wheel so the car can coast with as little mechanical drag as possible. Eking out every last bit of energy efficiency is crucial when fuel consumption is measured in drops.
Confalone is the driver who braves the car’s claustrophobic cabin. “The fastest we’ll ever go is 25 to 28 km/h,” she says. “But that feels really fast when I’m so close to the ground… It’s full throttle all the time, like an on-off switch. I turn it on, accelerate to a certain speed, and then coast for as long as I can.”
“Driving strategy is a huge part of what we do,” continues Wang. “Kristine integrates her knowledge of the track, her surrounding environment, and the technical specifications of the vehicle into this driving strategy we use. It took us years to develop… We even have to accommodate for wind.”
How does this translate to the real world?
“I definitely use brakes significantly less when driving around the road in my car,” says Wang.
“I’ll just drive really slow if I know I’m coming up to red light,” Confalone adds. “People are annoyed, but I’m like ‘I don’t care!’ When I’m driving this [Supermileage] car I don’t use the brakes at all.”
Joking aside, Wang points out the potentially huge implications of something like a driving strategy for autonomous or semi-autonomous cars.
If vehicles knew what the traffic situation ahead was, or knew when a traffic light was going to change, or what other cars on the road were doing, it could dramatically reduce fuel consumption. Perhaps the car could even coach a driver on how to be more efficient.
The way most of us drive, accelerating hard then slamming on the brakes between stop lights, is monumentally wasteful.
The other details that make the Supermileage car so efficient may be a little less practicable, at least today. The prototype is physically too small for any driver over 100 lbs. It doesn’t have a stereo, or air conditioning, or navigation, and although it’s very strong, it probably wouldn’t pass any standard crash-safety test either.
And then there’s cost. Carbon fibre, for example, is still expensive to mass-produce, although companies like BMW and Audi are making big strides. “Those limitations are more market-driven, so we’ll have to just kind of wait,” says Wang.
The UTSM team explaining their car to other students at a public function (courtesy UTSM)
However, much of the car’s efficiency comes from optimizing systems that already exist and using them in a more effective way.
“In terms of the size of vehicles, I think you could see that decrease,” says Confalone. “When you live in a city like Toronto – that has no parking and where gas is so expensive – the size of a vehicle really makes a difference.”
Smaller vehicles are lighter and require less energy to move. We’re already seeing car companies explore this idea. The street-legal Renault Twizy, for example, makes a smart fortwo look like a mid-size.
Despite the fact Shell sponsors the Eco-marathon, it seems most competitors see future cars going electric. It’s the fastest-growing sub-category among competing teams, who can choose the type of car they’d like to build.
Both Wang and Confalone see cars of the future going all-electric but acknowledge it’s not going to happen overnight. Battery technology is improving rapidly and the costs are decreasing, but how “green” those cars can be still depends on where your electricity comes from.
In Canada, our electrical grid is relatively clean, but it’s not the case in other parts of the world. In the meantime, Wang, Confalone, and the rest of the UTSM Team have proven the 150-year-old internal-combustion engine still has room for improvement.
(photo courtesy UTSM)
In 2015, the UTSM Team finished first in the highly competitive Prototype Gasoline class. From April 27 to 30, they’ll be competing in gasoline and electric categories, looking to once again take top honours at the Shell Eco-marathon.
If these are the young engineers who will go on to shape the future of the automobile, it’s going to be an exciting ride.