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The Loma Prietan
December 2001/January 2002My new Prius: Driving the future
by Dale F. Mead
What’s the latest in America’s love affair with cars? Well, the SUV is a fad past its prime; electric cars simply don’t work. Fuel cell vehicles will be the answer a few years from now. But to those of you concerned about the environment, I can boast that I’m driving the future: My new Toyota Prius.
Toyota Prius is small, but with a capacious family-car cabin featuring remarkable headroom, and several innovations that add up to clean, economical driving. (Photo: Dale Mead)So far there are two hybrid vehicles on the market. They are the Prius and the Insight, made by Honda. I can’t vouch for the Insight, having only seen a handful and never having driven one. It is essentially a hybrid roadster, a two-seater with a maximum load capacity of 275 pounds. Its market is far smaller than that of the Prius, a four-door sedan that can carry four people—five if they’re light. Its payload is 800 pounds.
If nothing else, Toyota has proven the market appeal of the Prius. People have had to wait weeks, even months for delivery. But my wife and I lucked out: Her son forwarded an e-mail from a friend who had lost his Silicon Valley job and needed to sell right away. It had only 6,000 miles on it, and he was willing to take a loss of $4000 if we paid cash. We test drove it on a Sunday and bought it the next day.
I understand the Insight is very well engineered; I know the Prius is. A lot of its attraction, in fact, is that it looks and feels very intelligently engineered. It has its flaws (I’ll discuss them later on), but overall, it delights us.
The Prius has the curvy-wedge style of newer cars, although it looks stubbier and and stands perhaps six inches higher (presumably to accommodate the batteries below the back seat). My wife describes it as cute. It drives easily, but its light weight and height give it less stable tracking, especially in the wind.
The car looks very different from the driver’s seat. First, it sports a dash-mounted, joystick-like lever just right of the steering wheel. It sets the transmission positions, just like a steering shaft or center console-mounted lever (except that, along with the standard Park, Reverse, Neutral and Drive, it has a “B” setting for “brakes” or “battery.”) Upon reflection, it’s probably the best solution; a shaft-mounted lever would compete with the windshield wiper and cruise control adjustments, and a console-mounted lever would oust the delightfully convenient center storage compartment and glass holder. Dash-mounted buttons would work, except that the dash has plenty of buttons already. Besides, once you get used to this lever, it’s a great conversation piece.
To its right you notice, in addition to the recessed and centered digital speedometer/odometer, a bright, three-by-five inch full-color LCD display that constantly updates one of two diagrams, gas consumption or energy use (you can switch between them). The energy use display diagrams the 70 horsepower gas engine, the 44 horsepower electric motor, the wheels, and the battery, joined by arrows that depict what the power train is doing at any given moment: Sometimes the gas engine is driving the wheels; sometimes it’s driving the wheels and recharging the battery through the electric motor. If you’re creeping through the parking lot, it will show that the battery is powering the electric motor, which is driving the wheels. At that point, you’re driving the world’s fanciest golf cart.
The “battery,” by the way, actually is an array of 38 7.2-volt nickel-metal hydride batteries under the back seat. If the array fails, replacement is nearly $5,000, a quarter the value of the car. Reassuringly, a 100,000-mile warranty covers it; and a Toyota parts rep says they almost never fail.
The computer-controlled power adjustments are a core factor in this car’s efficient performance. The prior owner put it aptly: Finally, computers are applying superhuman intelligence to driving. Instead of the driver controlling the engine directly, his actions convey what he wants to do; the car itself figures out how.
The energy display shows how Prius is being powered at a given instant. At this moment the gasoline engine is powering the wheels and supplying electricity to the electric motor to power the wheels. (Photo: Dale Mead)This display intrigued me most when I first started driving our Prius, but the gas consumption display has become my new computer game on the road. It actually has improved my driving. I find myself seeing if I can increase the gas mileage, and if driving 65 pays off in significantly better mileage than going 75. Hey, “Beat the Mileage Meter” is better than my old game, “Beat the Traffic.”
The U.S. Environmental Protection Agency rates this car at 52 mpg city, 46 mpg highway, but that says more about the EPA’s test methods than the car. No way is city driving more efficient than highway. Good mileage requires steady driving, which can’t happen amid intersections and traffic lights. We get about 47 mpg on the highway and 37 mpg in the city, or 40-44 mpg on average.
The display shows gas consumption three different ways: A dynamic bar graph displays the average gas consumption every five minutes out to 30 minutes, updating as you drive. It makes graphically clear the effect of going up versus down inclines, as well as steady driving versus stop-and-go. Another bar displays instantaneous or “real-time” gas mileage, from 5 mpg when you’re accelerating to 100 mpg coasting down hills. The third readout, at the bottom, shows the long-term gas mileage since it was last reset. This gauge is about 2.5 mpg on the optimistic side, showing roughly 44.5 mpg when we get 42 mpg.
The consumption display shows miles per gallon over 30 minutes in 5-minute increments (bar graph), at any given instant (right bar), and over a number of miles driven (bottom). If our use of all devices were monitored this clearly and constantly, Americans undoubtedly would use energy far more prudently. (Photo: Dale Mead)Inside, the Prius sounds as different as it looks. It’s remarkably quiet, particularly when powered only by the electric motor. It can sneak up on pedestrians and bicyclists, so we have to be extra careful around them. Most startling, however, is when the engine turns off at red lights and the car becomes as silent as if parked. You have to resist the urge to crank the ignition when the light turns green.
Other times, the car is unexpectedly noisy, such as going uphill, where it whines as if the clutch were slipping (if it had a clutch) while the power remains firm and steady. What you’re hearing is another breakthrough technology: the continuously variable automatic transmission. Unlike standard automatics, which shift through three or four gears, this one uses the optimal gear ratio to keep the engine spinning at the most fuel-efficient speed.
Downhills reveal the third key technology: regenerative braking. Take your foot off the gas and the electric motor creates drag, slowing the car and recovering its energy by putting electric power back into the battery. Regenerative breaking is as old as electric vehicles; the surprise is that Toyota estimates it recovers 30 percent of the energy. That’s where the “B” lever setting comes in: on a long downhill, you can shift to “B” to recover even more energy. The gas consumption display, by the way, gives you a gold star for every 50 watt-hours you recover.
No car is perfect, of course. The seats don’t provide sufficient back support or adjustments. The one minor but maddening instance of dumb engineering is the “Display” button on the dashboard. Press it and it lets you turn the energy display off. Press it again and nothing! The “Info” button turns the display back on. Go figure.
But all in all, we’ve gotten more than our money’s worth, especially if it’s true that Toyota sells every Prius at a loss. It has the DVD player, cup holders, remote locks and other touches that we have long coveted while driving our 16-year-old Honda Accord to 240,000 miles. The state-of-the-art design also achieves emissions that are one-tenth that of comparable automobiles, earning an EPA rating of Super Ultra Low Emission Vehicle.We plan to get cruise control, standard on newer models; that should make getting maximum fuel efficiency close to effortless.
We’re driving the future and enjoying it—and gloating shamelessly about being Environmentally Correct. I recommend it.
In weather too wet for cycling to work, author's wife, Janice, now can drive the Prius. (Photo: Dale Mead)Dale F. Mead is a frequent contributor to the Loma Prietan.
