Hybrid Cars achieves 68.7 mpg in 2012 Honda Civic Hybrid

2012 Honda Civic Hybrid

Yuuji Fujiki, chief engineer for Honda’a IMA hybrid system, holding the battery pack used in the 2012 Civic Hybrid. (Photos: Brad Berman, All rights reserved.)

The new 2012 Honda Civic Hybrid, using a lithium ion battery for the first time, increased its average EPA fuel economy rating from 41 mpg to 44 mpg. The new model is rated at 44 in both city and highway driving. HybridCars.com, using hypermiling techniques, achieved the upper limit of what any driver should ever expect for fuel efficiency—a score of 68.7 mpg on a 10-mile course of mostly country lanes and some highway driving, with four or five stoplights along the way.

The improvement in fuel economy solidifies the Civic Hybrid’s second-place position for fuel economy among cars that don’t plug into the grid. The 44-mpg average moves the Civic slightly closer to the Prius’s 50-mpg level, and edges out the 42-mpg Lexus CT 200h. Honda makes the claim that the Civic Hybrid becomes the most fuel-efficient sedan—meaning it’s not a hatchback—on U.S. roads.

The all-new, ninth-generation 2012 Honda Civic arrives at dealers nationwide starting today. The MSRP for the Civic Hybrid begins at $24,050, and tops out at $26,750 for the package with leather, XM radio and leather.

Like other new Civic models—there are now five different versions, including the HF high fuel-effeciency non-hybrid model—the 2012 Civic Hybrid gains new features and sleeker styling.

Bigger Engine Means More Electric Power

In addition to the shift to lithium ion batteries, the 2012 Honda Civic uses a larger 1.5-liter 4-cylinder engine. “We changed the displacement from 1.3 to 1.5 liters,” said Yuuji Fujiki, chief engineer for Honda’a IMA hybrid system, in an exclusive interview with HybridCars.com. “But the fuel consumption rate is the same as current model.” Fujiki explained that the larger displacement allows the engine to run at lower RPMs, which in turn allows for more frequent use of the electric motor and produces a quieter ride.

The rear seat of the 2012 Honda Civic Hybrid is cut away to show placement of the lithium ion battery pack.

The Civic Hybrid’s lithium ion batteries are 30 percent smaller than the previous nickel-metal-hydride batteries—thereby granting more cargo space than the previous model.

Fujiki expained how every aspect of the hybrid system’s design was tweaked for optimal efficiency—such as the motor that increases output from 15 kW to 20 kW, uses more coils and widely spaced magnets, and employs plastic spacers to better manage temperature.

In addition to more frequent use of idle-stop, the engine valves are sometime deactivated to cut off fuel, even when the engine is turning. Honda refers to this as EV mode, although Fujiki admitted that it’s not a true all-electric condition. “It’s not electrical only,” he said. “The fuel system is stopped, but there is a mechanical drag.” Fujiki said that, at maximum output, this “no-fuel” mode could last up to 79 seconds.

All About Balance

The focus of Honda engineers was on total vehicle efficiency—evidenced by a remarkable 44-mpg average using a single-motor system that’s less expensive and complex than the Toyota two-motor approach. “We had to strike a balance between engine friction, motor output, and how to use the battery,” said Fujiki. “That balance is going to determine the overall efficiency.”

Honda's IMA hybrid system, shown with the transmission removed for easier viewing.

Our interview with Fujiki helped us win the MPG challenge, which was established by Honda for journalists attending the media preview for the 2012 Civic earlier this month in Washington, DC. His advice—to accelerate in a steady manner to about 45 miles per hour and stay at this speed for as much of the 10-mile course as possible—was the key to achieving the winning 68.7 mpg score. Fujiki also advised not to use the neutral gear when coasting.

“Don’t use neutral, because when idling, fuel is injected,” he said. “Keep it in Drive, so the engine can judge that you’re decelerating, and get into fuel-cut mode and so you can take advantage of regenerative braking.”

Six-Percent Hybrid Take-Rate

The new Civic HF sedan, positioned between the Civic LX and Civic EX, is rated for 41 miles per gallon on the highway and 29 in the city. It is equipped with a 5-speed automatic transmission, exclusive 15-inch lightweight alloy wheels and aerodynamic enhancements under the body, and a rear spoiler. It does not use any hybrid drivetrain technology or idle-stop features. Driving in exactly in the same manner in the HF as we did in the Civic Hybrid, we achieved 46 mpg on the 10-mile course. The MSRP for the 5-Speed Automatic HF model begins at $19,455.

All Civic models, except for the Si, now feature an “econ” button allowing drivers to maximize efficiency on demand.

Consumers will recognize the Civic’s raked windshield, wide stance and other styling features that do not dramatically depart from the current model. The hybrid has a unique grille design with blue accents. Special five-spoke alloy wheels, a decklid spoiler and LED brake lights further differentiate the Civic Hybrid from other Civic models. The interior of the Civic Hybrid uses exclusive seat fabric and unique door panel covers. The hybrid offers a range of standard and available audio and navigation technologies.

Honda expects to sell a total of 260,000 Civics in a year—with about 6 percent coming from the hybrid’s sales, and another 2 -3 percent from the HF model. That means about 1,300 sales of the hybrid per month—a fraction of Prius sales. Honda executives admitted that the company’s hybrids were primarily targeted at other global markets, such as Japan.

Source: Hybrid Cars