VT-REX Makes Gas Guzzlers Look Like Dinosaurs

ByMarianne Lavelle
June 24, 2011
3 min read

One of the problems with the fuel alternative ethanol is it doesn’t pack as much energy density as gasoline—meaning fewer miles per gallon. But students from Virginia Tech University have proven that with the right technology—and that includes an electric motor—it’s possible to engineer a vehicle that will get the equivalent of 81.9 miles per gallon (35 kilometers per liter) on ethanol.

Virginia Tech won the U.S. Department of Energy-sponsored EcoCAR competition—a three-year contest among 15 collegiate teams to retrofit General Motors-donated vehicles for super energy efficiency.

The Virginia Tech students used as their base vehicle the cross-over sport utility vehicle, the Saturn Vue, which is no longer produced since GM’s reorganization in 2009. They retrofitted it with an electric motor and battery system capable of delivering an all-electric range of 54 miles (87 kilometers). They backed that up with a 2.4-liter GM engine capable of running on either 85 percent ethanol (E85) or gasoline. See the details on a “virtual car” at the team web site.

Virginia Tech team co-leader Lynn Gantt (read more about him on the Energy Department’s blog) said some questioned the team’s use of such a large engine. And the team was hampered because they would be judged on tailpipe emissions, but the students didn’t have facilities to do emissions calibration in their lab. But they made sure that the FlexFuel engine was tuned to run on E85 and 15 percent gasoline. In the end, running on ethanol gave VT-REX (Virginia Tech Range Extended Crossover) a distinct advantage in the competition, since the only vehicle with lower tailpipe emissions was a hydrogen fuel cell vehicle (which, of course, had zero tailpipe emissions.)

Energy Secretary Steven Chu at the finish line

The EcoCAR competition (formally known as EcoCAR: The NeXt Challenge) is one of a number of student engineering contests for high efficiency vehicles. (See photos of cars in Shell’s Eco-marathon Americas and Eco-marathon Europe earlier this year.) After the winners were announced last weekend, Energy Secretary Steven Chu and Kent Helfrich, executive director, electronic controls and software for General Motors, emphasized one of the key aspects was to prepare the young engineers for jobs in the auto industry.

“The thing that really drives us is the ability to work with these engineers, to train them on the latest cutting-edge tools and help them enter the automotive industry with great careers ahead of them as innovators,” said Halford. Indeed, Gantt said the majority of the 24 VT team members were bound for jobs with automakers and suppliers; he himself is heading to Michigan this summer to work for GM.

With average U.S. vehicle fuel economy still 22.5 mpg, let’s hope the influx of young engineers with talent and training at efficiency helps drive up mileage in the years ahead. “We’re proud of what they’ve accomplished,” Chu said of the students, “and look forward to seeing what they do in the future.”

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