By Larry E. Hall
As one observer commented, the Chevrolet Volt is one of the most politically “charged” cars ever produced. Politics aside, the Volt is a remarkable automobile that delivers exactly what General Motors said it would when the concept was introduced at the 2007 North American International Auto Show in Detroit. And when the production car arrived in late 2010 as a 2011 model, automotive journalists deemed the Volt significant enough to select it as the 2011 North American Car of the Year.
The Volt enters its third model year with the same base price as the outgoing 2012 model, $39,145 before federal or state incentives. That’s not all of the good news, however. Engineers tinkered with the recipe of the lithium-ion battery’s chemistry to gain a few extra miles of electric range – 38 miles compared to 35 miles for the 2012 edition. The officially rated miles per gallon equivalent (MPGe) also increases to 98 MPGe from 94 MPGe.
The 2013 Volt arrives in the North American market with a new “Hold” drive mode, which allows the car to operate on gasoline only and save the battery for later. This feature was first seen on 2012 European market models to enable drivers to save the electrons for green urban zones where emissions are penalized. Also new are two safety features as part of the Enhanced Safety package: lane-departure warning and forward collision alert. Additional changes include a new power gauge, an optional rear-seat armrest and new exterior and interior color choices.
Simple, Yet Complex Powertrain
At first glance, the Volt’s drivetrain is a somewhat simple series hybrid design: A small gasoline engine powers an electric motor-generator that produces electricity that sustains a battery charge and is then directed to an electric motor that powers the front wheels. This type of hybrid powertrain is not new, and in fact, General Motors toyed with the idea in 1969 with the Stir-Lec II, a second-generation experimental hybrid vehicle that operated similarly to Volt. A big difference between the two is the Volt’s battery can be charged by plugging in to either a 120-volt or 240-volt home electrical outlet.
The hybrid design may be simple but the complexity under the Volt’s hood is staggering. The car doesn’t have one electric motor; it has two—a 111-killowatt (148 horsepower) main traction motor and a 55-kw (73 horsepower) generator motor. A 1.4-liter 64 horsepower four-cylinder engine doesn’t drive the wheels – it only kicks in to power the generator motor to sustain the battery charge enough to give the car an extended range of 300-plus miles. And that only happens once the battery is depleted.
Speaking of the battery, when the concept Volt was introduced in 2007, GM stated that to make it a reality required a large lithium-ion battery weighing nearly 400 pounds. At the time, some experts predicted that such a battery could possibly be production-ready by 2010 to 2012. Other experts said the technology was 10 or more years away. Not quite four years later, the Volt arrived with a 5.5-foot long T-shaped 16-killowatt hour lithium-ion battery. Weighing 435 pounds, the battery is incorporated into the frame beneath the passenger compartment along the center tunnel and is liquid cooled and heated to keep the 288 cells in the optimal temperature range.
Charging the battery – which the aforementioned chemistry tweaks upped to 16.5 kwh this year – is a simple task, simply plug the supplied charging cord into a 120-volt household outlet and then plug the other end into the charge receptacle on the Volt. An alternative is an optional 240-volt charging unit that cuts charge time significantly. With the new battery chemistry, charge times are increased slightly: a 120-volt outlet could take 10.5 hours and 4.25 hours to charge when using the optional 240-volt charger (up from 10 hours and four hours, respectively).
The drivetrain’s final component is a planetary-geared single-speed transmission. It operates in conjunction with three independent clutches to manage and distribute power from either or both of the electric motors and gas engine to the front drive wheels. For example, during certain cruising situations to obtain maximum efficiency, torque from the gasoline engine is blended with the small motor generator to supplement the drive motor. While the gas engine mechanically assists the drive motor, it does not power the Volt by itself.
While computer programming decides the drivetrain’s most efficient operation, the driver can play a role with four different driving modes: Normal, Sport, Mountain and the new Hold mode. When the car is powered on, the default mode is Normal and delivers a typical accelerator feel. Selecting Sport provides a livelier accelerator response with the downside of using more electrons from the battery. Mountain mode is for, well, traversing mountain terrain. It helps maximize performance by maintaining a sufficient charge so that extra power needed to negotiate steep grades comes from the battery and needs to be engaged well in anticipation of heading for the hills.
The Hold feature as found also on European Volts and near twins Opel/Vauxhall Amperas, essentially “holds” the battery state-of-charge level allowing for pure electric driving at a later time in the journey.
Additionally, the driver can shift to Low instead of Drive for more aggressive regenerative braking. It conserves energy by changing the throttle and brake settings so you have to brake less – lift off the accelerator and the car dramatically slows down.
Chevrolet doesn’t position the Volt as a plug-in hybrid, but as an “extended-range electric vehicle,” which in practice means it falls somewhere between an electric car and a standard gasoline-powered car. The Volt operates entirely as an electric car for its first 30 to 40 miles after a full charge of the battery – with extreme cold possibly reducing range to as little as 25 miles, and judicious or slower speed driving possibly increasing electric range to 50 or more miles.
The engine doesn’t drive the wheels – it only kicks in to power a generator motor that sustains the battery charge enough to give the car another 300 miles or so of range once the battery is depleted.
Exterior
The production Volt looks nothing like the sporty, coupe-like concept that debuted at the 2007 Detroit auto show. Instead, reality dictated that it needed a more conventional, functional shape for aerodynamic reasons and to accommodate people and the things people haul along.
For the Volt’s design, Chevrolet uses a shape that’s come to define hybrid and electric vehicles: a four-door hatchback with a smooth front and a high, abrupt tail. The truncated rear, called Kammback, is a design shape that reduces the air resistance of the vehicle. The tail’s low drag contributes to the Volt’s drag coefficient of 0.28 that helps eke every last mile from the battery.
While its general profile resembles the Honda Insight and Toyota Prius, the Volt is clearly a Chevrolet with the trademark twin-bar front grille leading to headlamps that sweep into the front fenders. Optional seventeen-inch polished aluminum wheels add a touch of style to the judicious use of chrome and piano black over the window line.
Interior
Volt’s cabin blends Chevy’s traditional twin-cockpit design with a dashboard that looks more like an advanced hub of operations than an instrument panel. Instead of traditional gauges, the driver faces a seven-inch LCD screen displaying speed, odometer/trip distance, battery level and electric driving miles to go. There’s also a meter with a green revolving ball that indicates hard acceleration or hard braking – keep it in the middle and you’re driving efficiently. When the battery is depleted, a gas gauge replaces that meter.
The center stack eschews conventional switchgear in favor of an iPod type flat, touch-sensitive control panel for audio and climate settings. However, attempting to use them without intimate familiarity will result in hurtling down the road like a drunken sailor. Above the panel is a second seven-inch display screen that shows the usual infotainment and climate control details, but also power flow, energy usage information and charging details. It is also the screen for the optional navigation system.
Geeks will relish using the available mobile apps that can run on an iPhone or Android system. With a smartphone owner’s can access their vehicle’s current electric range, check the battery’s charge level, manage battery charging times and check what time the car will be fully charged and ready to go. Other functions can be performed remotely also—like remote start or unlocking doors. With just a couple of taps, the Volt can be pre-cooled in the summer and pre-warmed in winter.
The cabin is the best Chevy interior available with high quality materials and grains. Up front, head- and legroom are generous and front bucket seats are pleasingly comfortable. A height-adjustable driver’s seat and tilt/telescopic steering wheel make it easy to adjust for a good driving position. Rear seating is reduced to two because of the intrusion of the battery’s center location. Legroom for back seat passengers is adequate for most, but those over six feet will be uncomfortable.
Volt offers an arm’s length of standard convenience features as expected in a car with a sticker price of nearly $40,000. Included are keyless entry, power windows, locks and mirrors, automatic climate control, OnStar assistance, SiriusXM satellite radio, Bluetooth wireless cell-phone link as well as USB and iPod connectivity. Optional are leather seating, a navigation system and a package that includes a rearview camera and front- and rear-obstacle detection.
Expected safety gear includes all the biggies—eight air bags, anti-lock disc brakes with brake assist, electronic stability control and traction control. The federal government gives the Volt a safety rating of five stars overall.
Driving Impressions
Whether driving on a fully charged battery or after the gas engine comes on to maintain the battery pack’s state of charge, the Volt behaves just like a pure electric car; speedy, smooth, and whisper-quiet. Since the electric motor is the main mode of motivation for the car, take-offs from a start benefit from typical EV low-end torque. In this case, 273 pounds-feet of torque – a number you’d see in V6 engines. Zero to 60 mph arrives in a tick or two less than nine seconds, an indicator that merging into high-speed traffic is easily accomplished.
The Volt didn’t major in driving excitement, but it is surprisingly fun to drive and dispenses predictable front-wheel drive handling. GM obviously took care to engineer in above-average compact car road manners. With the Sport mode selected, and shifting to Low when required, the Volt is up to the task of negotiating curvy roads, holding sharp corners commendably well. With 435 pounds of batteries running down its spine, the center of gravity is low, favorable for gripping the road and minimizing body lean.
Unlike many electric power steering systems, the Volt’s is communicative with good on center feel and offers decent driver feedback. As for the quirky, almost brick-like feel of most regenerative brake systems, braking is solid and linear with the computer blending regenerative and mechanical brake force seamlessly.
An independent strut-type front and a semi-independent torsion beam axle rear suspension are typical of cars in the compact class. Engineers have tuned it with soft spring rates and matching shock rates for good comfort and control. The setup absorbs the bumps and potholes of everyday driving quite well.
Low cabin noise intrusion plays a role in perceived ride quality. Chevy has made road and wind noise almost nonexistent in the Volt. A key test of the Volt’s quietness is when the little 1.4-liter engine that powers the generator turns. On occasion you can hear the engine, but mostly you can’t.
All this adds up to a four-passenger family sedan that is a superb EV commuter that can turn into a comfortable highway cruiser with the ability to add a dose of driving fun.
About That Fuel Economy
That short sentence at the bottom of the window sticker regarding fuel economy—“Actual results will vary for many reasons” – applies to Volt perhaps more than any other vehicle. When it comes to overall fuel economy (MPGe), individual results posted on
fueleconomy.gov show a range of 39 to 1,462 mpg with an average of 175.4. As for electric-only driving range, reports of 40 miles shows up frequently on GM-Volt.com with several Volt owners reporting 50-plus miles on a single charge and a handful have broken 60 miles.
We have driven slightly more than 1,000 miles in 2010, ’11 and ’12 models. We have recorded EV mileage as low as 28 (heavy foot in Sport mode) and as high as 48 miles three times. Our MPGe was 139.5. We haven’t tested a 2013 edition so we can’t report on the Hold mode and how it can affect fuel economy.
The Green Car For You?
Intangible considerations giving a leg up to the Volt are it presently tops Consumer Reports’ rankings for owner satisfaction at 93 percent, has won a laundry list of awards and accolades, and GM is coddling Volt consumers with exceptional service. The company has a team of Volt Advisors ready to explain questions, or help with concerns, and this policy has been in effect since the car was launched to minimize potential complaints, and appears to be working well so far.
Regardless of how you view the Volt, it delivers electric car efficiency and unlimited fuel economy if you drive like 80 percent of American drivers, 40 miles or less a day. And, there is no perceptible difference in driving performance between battery electric power and when the gasoline powered generator starts up.
At first glance, the $39,145 sticker price can be a shocker. The $7,500 federal tax credit takes some of the sting out of the price plus, there are numerous state credits. Additionally, in some states the Volt gets solo High Occupancy Vehicle (carpool) lane status. For some commuters that alone is worth the price.
Like any vehicle that plugs in, you do have to have access to at least a 120-volt electrical outlet, and preferably a somewhat costly 240-volt home charging device. If you can live with seating that only accommodates four, then Volt could be the green transportation choice for you. If not, there are alternatives.
Toyota’s Prius Plug-in Hybrid is currently the closest Volt competitor. The base model is priced starting at $32,000 with the Plug-in Advanced model priced at $39,525, and like the Volt, various incentives are available although not as much. The Prius delivers better gas mileage in the gas-hybrid mode, but the Volt has more than double the range of electric-only driving.
If you’re looking for a pure electric vehicle, Nissan’s Leaf is available in two models, the $35,200 SV and $37,250 SL. While the Leaf’s electric driving range is 100 miles, there is no back-up gasoline engine to continue driving. It’s good for short commutes, but road trips are out.
The Volt’s price puts it in the same territory of near-luxury models like Cadillac’s CTS, the Acura TL, Lexus ES 350 and top-end Chrysler 300 models. The Volt is an excellent automobile, but is it a near-luxury compact car? Most buyers will overlook that anomaly because they will be buying a landmark automobile with technology that backs up the price.
Prices are manufacturer suggested retail price (MSRP) at time of publication and do not include destination charges, taxes or licensing.
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