When the talk turns to fuel-thrifty vehicles, hybrids get the most attention. Those are the vehicles people have heard about-more so than electrics and other alternative-fuel possibilities. Toyota's Prius earns credit for keeping hybrids in the public eye over the past decade, though Ford has done an admirable job promoting its Fusion Hybrid, as well as its earlier Escape Hybrid. Honda, meanwhile, is effectively touting the merits of its new CR-Z Hybrid sport coupe, helping to overcome the image of hybrids as sensible but somewhat dull vehicles.
Are You Ready for a Hybrid?
- Yes, if you're concerned about fuel usage, fuel costs, and/or the environment—and are willing to pay more than you would for a comparable gasoline car.
- Yes, if a gearless continuously variable transmission (CVT—used in many hybrids) makes sense and feels acceptable on the road.
- Yes, if you'd rather slash fuel usage than hurtle ahead at breakneck speeds when a stoplight turns green, or a highway opens up ahead. Yes, if the idea of a gas engine shutting off when not needed is appealing–or at least, not disconcerting.
- Yes, if you'd like to make your environmental concerns known.
- No, if high performance is a prime motivator.
- No, if you absolutely must have a big truck–though several hybrid biggies do exist.
- No, if you savor and demand the feel of a powerful engine and conventional gears.
- No, if you aren't especially concerned about fuel usage and environmental issues, and don't want to be seen as supporting fuel-efficiency.
- No, if you don't want to be considered out of the mainstream when behind the wheel.
What Is a Hybrid?
Hybrid vehicles operate using two power sources, typically working in tandem:
- A conventional gasoline (or diesel) engine–often, but not always, comparatively small.
- An electric motor (or motors) driven by a rechargeable battery pack.
A battery pack provides electricity for the motor, or it can be supplied by the gasoline engine, working as a generator. Computer control determines whether the vehicle should be running on battery power, the conventional engine, or both at once. When accelerating, both the gasoline engine and the electric motor will almost certainly be providing power to the wheels. While cruising or slowing down, energy may actually be traveling back to the battery pack, enhanced by regenerative braking. Transitions between power sources are close to seamless, barely discernible to the driver.
All current American hybrids have a gasoline engine and an electric motor. But diesel could replace gasoline as the liquid fuel. Most use a gearless continuously variable transmission (CVT), though some have conventional gearing like a regular car.
Dual-mode (parallel) hybrids can work on either gasoline or electric power, or both together. A computer determines the best balance between the two, depending on driving conditions. Parallel hybrids can run for a short distance using battery power alone, with the gasoline engine shut off completely.
"Mild" (series) hybrids cannot run on battery power alone. Partly for that reason, their fuel economy compared to a regular vehicle isn't nearly as appealing.
How Hybrids Work.
Driving a hybrid may be disconcerting at first, but mainly because nothing necessarily happens when you switch it on. Unless it's cold, the gasoline engine may not start until it's needed. With dual-mode hybrid powertrains, the car can start off slowly using battery power alone. At some point-usually within a mile or less-or when you reach a certain speed, the gas engine comes into play. Push too hard on the gas pedal, too, and the gas engine springs to life. Some hybrids can travel several miles on electricity alone, if the driver's foot is truly gentle on the accelerator.
Unlike pure-electric vehicles, hybrids never need to be plugged into an electrical outlet. Their batteries charge while driving. Electricity is generated by the gasoline engine, and also by regenerative braking, which captures some of the energy that would otherwise be lost when slowing to a halt.
Gasoline engines usually shut off when the vehicle is stopped, to conserve fuel. Some will shut off when slowing down, or even when cruising lightly. Depending on the system, various conditions (such as the air conditioning running) will prevent the gas engine from shutting off. Indicators and/or diagrams on the instrument panel often show what's happening: which power source(s) are active, how fuel-efficiently you're driving, and so forth.
Hybrids have no range limitation. If the battery is too far discharged to power the electric motor, the vehicle runs on the gasoline engine alone until sufficient recharging has taken place. Thus, the only practical range limit is determined by the size of the gasoline tank.
Although the hybrid-powertrain concept dates back to around 1900 and the work of Dr. Ferdinand Porsche, not until computers became available did the idea become truly feasible.
Hybrid-powertrain vehicles have been sold in the U.S. since 2000, when Toyota launched its first Prius and Honda introduced its initial Insight-a lightweight, subcompact two-seater. Sales never reached automakers' expectations until the fuel crisis of 2008, when gasoline topped $4 a gallon.
Suddenly, hybrid cars that had languished on dealer lots found eager buyers, some willing to pay more than sticker price for a fuel-efficient automobile.
In the first-generation Insight, the gas engine was dominant, with the electric motor providing additional thrust when needed. That Insight could not run on battery power alone. Toyota's Prius was just the opposite, with battery power dominant and gasoline the supplement. That configuration became the norm.
Fuel economy is Number One, because the gasoline engine (often smaller than usual) isn't always running. Exhaust emissions also are reduced.
Hybrids also are quiet when the gasoline engine is shut off-though blind pedestrians aren't pleased with that aspect. Several manufacturers have been considering the addition of noisemaker devices, to warn pedestrians of the car's presence.
Saving money isn't the only reason to go hybrid. In fact, economists estimate that it takes a number of years to recoup the extra sum a hybrid vehicle costs, by savings in gasoline.
Cutting down on emissions is a prime motivator for the environmentally conscious. Besides, reducing the amount of fuel consumed is a benefit to the country, even if it doesn't pay off personally. Every gallon of fuel that isn't consumed to drive one's automobile is a gallon that doesn't have to be purchased from a foreign source.
Toyota currently leads the fuel-economy race with its Prius, redesigned for 2010. The Environmental Protection Agency (EPA) gives it an estimate of 51 mpg in city driving and 48 mpg on the highway. Honda's Insight and Civic fall somewhat short of that estimate, at 40/43 mpg (city/highway). Ford's Fusion Hybrid manages a 41-mpg estimate in city driving, but only 36 mpg on the highway. Other hybrids are less thrifty, down to 17-mpg city/19-mpg highway for BMW's ActiveHybrid X6.
Fuel economy of certain hybrids isn't all that much greater than a comparable gasoline-engine model. Several current hybrid powertrains are installed in big SUVs, or even full-size pickup trucks. Every little bit helps, but even when driven gently, heavyweight hybrids aren't going to get phenomenal gas mileage.
Limitations and Drawbacks.
Some hybrid limitations are real; others are commonly thought but not necessarily accurate. Acceleration inevitably becomes an issue, as people perceive hybrids to be sluggish. Yet, some hybrid models are quite spirited, and others wholly adequate as long as expectations are realistic.
Complexity is another concern. Computer control is intricate, but normally trouble-free, operating outside the driver's awareness. Hybrids have proved to be about as reliable as ordinary vehicles.
Battery life and safety are common concerns, but neither has been a significant issue. Manufacturers report periodic battery-pack replacements, some due to accidents, but without incident. Batteries would indeed be expensive to replace, but hybrids (and electric cars) have relatively lengthy warranty coverage for that part of the powertrain.
Price is probably the foremost drawback, and it's one that isn't likely to be eased anytime soon. Hybrids simply cost more to build, and therefore cost more to buy.
Similarities and Differences Among Available Models.
Basic structures of the hybrids currently available are quite similar. Differences lie mainly in the details of everyday operation.
Some hybrid powertrains in recent years have been "mild" single-mode (series) type, which means they cannot run on battery power alone. Their engines do shut off at stoplights to save fuel. "Full" dual-mode (parallel) hybrids can run on the battery alone (for a short time), the gasoline engine alone, or a combination of the two. Because their gas engines may shut off more often, those tend to be the most fuel-efficient.
Regardless of model, the driver never has to give it a thought. An internal computer carefully determines which power source to use for each situation that arises during a drive, reevaluating constantly.
No particular benefits apply to a "dedicated" hybrid (like Prius), versus a hybrid powertrain as an option (as in Ford's Escape). Only a few are dedicated hybrids, available no other way, including the Toyota Prius, Honda Insight and CR-Z, Lexus HS 250h, and coming-soon Lexus CT 200. In the others, the battery/gasoline powertrain is essentially an extra-cost option for a regular vehicle.
How much extra does a hybrid powertrain cost, and can it be recouped in fuel savings? Such figures are virtual secrets. Numbers that exist out there are educated guesses. Yes, a portion of the purchase price can be recouped in fuel savings, but very gradually and most likely not in full.
People considering a hybrid probably heard about tax credits and other benefits. Sorry, you're too late. Federal tax credits have expired as a hybrid model gained popularity-presumably no longer needing special incentives. According to the Environmental Protection Agency (EPA), no federal tax credits for hybrids are available after 2010. State or regional tax credits might be offered; check with your local authorities.