Then they ripped out most of the car's innards. Researchers have found that cars using just batteries for power have a short driving range, perhaps 50 to 120 miles. Many parallel hybrids, for example, power the wheels with both the electric drive motor and the internal combustion engine. After much research by the modeling team, MTU chose the series hybrid configuration, which utilizes the gasoline engine to produce electricity, while the electric motor drives the wheels. The batteries are used for temporary energy storage.
Power is drawn from the battery pack with a heavier power demand.
The vehicle modeling team had to decide what was reasonable for the students to achieve. Graduate student Cornelius Opris, modeling team chair, said after looking at the judging criteria, they needed to know how each parameter required by the competition would affect the mileage, and they needed to weigh the interaction of the criteria. The team designed their own computer program to give different estimates, which led them to the basic approach and control strategy of the vehicle. Using fundamental principles, they calculated the vehicle power requirements, based on the EPA city and highway driving cycle. The key strategy was to operate the engine at its most fuel-efficient condition through these cycles, while meeting the power requirements through the use of the electric motor.