MARYSVILLE, Ohio -- Most of the attention for Honda's Accord hybrid will come from its eye-popping 50-mpg EPA city rating and under-$30,000 starting price. But those with an eye for engineering will see a creative combination of new technology with elements from the Chevrolet Volt, Toyota Prius and Ford Fusion Hybrid.
"Honda put in all we had," said Koji Ninomiya, chief engineer for the Accord Hybrid, through an interpreter. "We did our best, and we ended up at 50 mpg."
The car, which gets to dealerships in late October, uses three drive modes to crack the 50-mpg figure -- something no other mid-sized car, including the European diesels, can match.
Ninomiya said 50 mpg or any specific number was not the goal when Honda engineers began nearly a decade ago studying a new hybrid powertrain to replace its current design.
"We considered everything, [including] driving resistance and regenerative braking. We made the powertrain all new, and the biggest purpose of this was to aim for the most efficient system in the world. As we tried to optimize the efficiency, we decided two motors will be best," he said.
Here's how the two electric motors work in the Accord Hybrid's three drive modes, EV, Hybrid and Engine.
- EV mode: The car is propelled only by an electric motor powered by the lithium ion battery pack. The top speed is about 60 mph, but the range is very limited, just a few miles. Once the battery is depleted, the car automatically switches to Hybrid mode.
- Hybrid mode: The Accord Hybrid works a lot like a Chevrolet Volt. The 2.0-liter gasoline engine powers a generator to create electricity for the electric motor. Honda calls the generator a motor, hence two motors. Only the electric motor, fed by the generator, moves the car in Hybrid mode.
- Engine mode: The electric motor is decoupled, and the Accord's Atkinson cycle gasoline engine drives the wheels directly through a one-gear transmission. In that highway gear -- similar in efficiency to a sixth gear on a manual transmission -- the gasoline engine runs in its sweet spot, delivering both strong acceleration when needed and high fuel economy.
Ford and Toyota hybrids also use Atkinson cycle engines. The Accord's Atkinson cycle 2.0-liter gasoline engine is a first for Honda.