From the Archives: Gleaning Green Transportation Ideas From NASCAR

"NASCARNASCAR isn’t the most obvious place to look for innovative ideas in green transportation. The typical stock car usually averages around four to six mpg—granted at speeds reaching 200 mph.

But for BMI Motorsports, an innovative racing team in North Carolina, there’s perhaps no better place to search.

That’s because the advanced modeling and testing that BMI conducts to get its cars running around the track faster is steadily building knowledge and techniques for optimizing the aerodynamics of ground transportation.

Historically, racing teams tested their designs in wind tunnels, tweaking nearly every feature within a narrow band of NASCAR’s allowable dimensions. But wind-tunnel measurements can be up to 20 percent off.

So, instead, BMI starts by generating a computer model of their cars and running it through computational fluid dynamics (CFD) software to optimize the design.

(This is the same kind of software that aerospace companies use to help tune the aerodynamics of a massive 747 or A320.)

According to BMI’s sister company Advanced Vehicle Research (AVR), which generates the models, decreasing the drag by 5 percent is equivalent to gaining 25 more horsepower for moving the car forward, faster.

Improving the downforce coefficient—a measure of how much downward pressure is created by the car’s aerodynamics—by 0.1 can increase a car’s lap speed by 1.8 mph. You’d need 70 more horsepower out of an engine to get the same result without rethinking the aerodynamics.

Solutions for the rest of us

The pursuit of speed is a NASCAR team’s end goal. But for the rest of us, better gas mileage would suffice.

In that, BMI and AVR’s research is proving quite useful. The same techniques that help reduce aerodynamic drag on a stock car can help engineers improve the aerodynamics of mass-market automobile designs so that our cars need less horsepower to maintain highway speeds.

Less horsepower, smaller engines. Smaller engines, less gas. All while maintaining the performance and acceleration we’ve grown used to.

And the research doesn’t stop with cars. As diesel prices soar, AVR has directed its attention to the aerodynamics of heavy trucks.

By year’s end, the company hopes to offer a suite of solutions that trucking companies can use to improve the gas mileage of a Class 8 truck—the kind we see most often on the Interstate—by 40 percent or more.

That effort has caught the attention of groups promoting energy efficiency such as RMI’s MOVE team and the EPA’s SmartWay program. Both now have their logos on BMI’s stock car in the Camping World Series.

As RMI’s recent research shows, the climate protection and economic benefits of more efficient tractor-trailers would be huge.

Noah Buhayar is a former fellow at Rocky Mountain Institute.
This blog was originally published on Yahoo Green in 2008.