05:19 19-05-2026

BYU Student Team Builds Super-Efficient Supermileage Prototype

Brigham Young University students built the Supermileage, a 49kg carbon fiber prototype achieving 0.11 L/100km fuel economy. Learn about its design and extreme compromises.

Students at Brigham Young University in Utah have built an experimental vehicle called the Supermileage, which achieves an astonishing fuel economy of roughly 0.11 liters per 100 kilometers. That said, it only vaguely resembles a conventional car. In reality, it's an ultra-light three-wheeled prototype designed for the Shell Eco-marathon, where the goal is to travel as far as possible on the smallest amount of fuel.

The body is carbon fiber, and the entire vehicle weighs just 49 kilograms. Driver requirements are equally strict: a maximum height of 163 centimeters and a maximum weight of 54 kilograms. That means this car wouldn't work for most people in daily driving.

Testing took place at the Indianapolis Motor Speedway. The prototype had to cover 10 miles (roughly 16 kilometers). To save weight, a conventional fuel tank was replaced by a tiny 30-milliliter ethanol container.

In theory, with that level of fuel consumption, the Supermileage could travel from Provo, Utah to New York City on just 3.8 liters. However, its top speed is a modest 23 mph (roughly 37 km/h). On a real road, efficiency would depend heavily on wind, road surface, and terrain.

The project's main purpose isn't to launch a production vehicle anytime soon. Instead, it shows how extreme fuel savings become possible when you drastically cut weight, enhance aerodynamics, and strip away everything non-essential. As automakers return their attention to hybrids, experiments like this serve as a reminder that the internal combustion engine still has untapped potential—but achieving record efficiency demands severe compromises.