With the 2005 leg of Challenge X: Crossover to Sustainable Mobility successfully completed, mechanical engineering professor Doug Nelson and the Virginia Tech Hybrid Electric Vehicle Team (HEVT) are turning their design for an ethanol-powered SUV into a working vehicle.

Nelson and the Virginia Tech engineering students are among 17 university teams selected by the U.S. Department of Energy (DOE) and General Motors (GM) to compete in the three-year Challenge X. Challenging engineering students to help develop designs and technology for the next generation of energy-efficient, low-emissions vehicles, the sponsors have given each team a Chevrolet Equinox SUV and $10,000 seed money, as well as up to $25,000 in automotive parts.

“From the beginning of the competition, our goal has been to reduce the petroleum consumption of the Equinox by 80 percent,” Nelson says.

The HEVT had hoped to use fuel cell technology, as they did in the past during the DOE-sponsored FutureCar and FutureTruck challenges. However, in the process of developing designs and finding components for Challenge X, they realized they wouldn’t be able to make fuel cells the primary energy source.

So they researched other alternatives and decided to use an E85 engine, which runs on 85 percent ethanol and 15 percent gasoline, which helps with cold starts.

Ethanol – long popular as grain alcohol – is a renewable fuel typically distilled from corn. In addition to achieving the goal of reducing petroleum consumption, the E85 fuel mixture produces fewer overall greenhouse gas emissions.

Through GM, the team has obtained a Saab 2-liter E85 engine, which Nelson and the students will integrate into the Equinox with a parallel hybrid electric drive.

“With the E85 engine and two battery-powered electric motors, we can use either to turn the wheels – or we can use them together,” Nelson explains. “The motors also can be used as a generator to absorb energy from the engine and recharge the batteries.”

E85 is gaining some serious attention from government and the auto industry. In 2004, Congress passed legislation that offers tax credits for building fueling stations that supply E85. So far, reports the National Ethanol Vehicle Coalition, about 600 U.S. service stations sell E85.

All three U.S. automakers and a number of foreign automakers produce limited lines of E85-compatible vehicles. In January 2006, Ford Motor Company announced development of a research model of the Escape SUV that combined hybrid-electric and E85 power – much like the technology designed by the Virginia Tech engineering team.

To succeed in Challenge X, the HEVT must produce a fuel-efficient, low-emissions Equinox that also retains all of its original performance and utility factors, such as cargo space, acceleration performance, and fully operating air conditioning.

In addition to primary sponsorship from DOE and GM, the Virginia Tech team has secured industry support that includes an electric drive train donated by Ballard, a battery pack donated by Cobasys, and control system hardware donated by National Instruments.

During this second year of the competition, the HEVT and other teams will take their vehicles to GM’s Mesa Desert Proving Grounds in Arizona to be judged on design, fuel economy, performance, and a number of other factors. After the summer event, the teams will have another year to refine their entries for the final competition event and judging in June 2007.

Among the 45 members of the current Virginia Tech HEVT are 30 mechanical engineering seniors, whose work on Challenge X constitutes their capstone design project. The team also includes mechanical engineering juniors and electrical and computer engineering and computer science students.

Since the HEVT couldn’t use fuel-cell technology to power their Equinox for Challenge X, Nelson and the students have developed a fuel-cell auxiliary power unit as a research project. Using fuel cell modules donated by Ballard, the HEVT is experimenting with the use of hydrogen fuel.