Monday, May 23, 2011

Auto: 2011 Chevrolet Volt

Electric Revival: Not only did it not kill the electric car, GM's reinvented it.

BY DAVE VANDERWERP, PHOTOGRAPHY BY ROY RITCHIE
October 2010 

Mass-produced electric cars are finally here. And, this time around, it appears they’re here to stay.
It’s irrelevant that, depending on how their electricity is produced, electric vehicles don’t come very close to living up to the zero-emission label they often receive. Also irrelevant is the point that battery packs with enough capacity to power a vehicle for any significant range are prohibitively expensive today. That’s because the trump card already has been played: It’s called government intervention. The Obama administration has started to unleash part of a planned $69 billion to thousands of clean-energy companies—through tax credits, loans, and grants—as well as to consumers, with a $7500 federal tax break for buying a car that has at least 16 kilowatt-hours (kWh) of energy stored in a battery pack. Do you think it’s a coincidence that the Chevrolet Volt’s lithium-ion pack contains exactly that amount?

But beyond the commonality of large battery packs, the Volt sets itself apart from the Nissan Leaf and the forthcoming EV crowd: It also has a gas engine that can step in to extend the Volt’s range when the battery’s energy is depleted.

This is why GM calls the Volt an “extended-range electric vehicle,” and the dual-power-source arrangement makes a lot of sense at a time when there’s precious little charging infrastructure. Currently, 48 of 50 states have fewer than 10 charging stations, and even California’s relative abundance of 422 pales in comparison to its roughly 10,400 gas stations. In other words, it’s going to be some time before charging while at work or out on the town becomes the norm; for now, EVs’ batteries will be replenished largely at home. And with maximum ranges in the 100-mile neighborhood, good luck with any long- or even moderate-distance travel. And forget about having a pure electric as your only vehicle.



What if your family in California needs you to visit? While a pure EV—needing long recharging sessions every 70 miles or so—will transport you back to the era of the monthlong road trip, the Volt could easily drive across the country on gas when there’s no time or electricity available for recharging. Closer to home, if this writer had been driving a Leaf instead of a Volt, I would have had to deal a blow of rejection to a five-year-old nephew  whose birthday party was 60 miles distant, due to the lack of a place to charge while there. Do you think he would have understood?

And although the Volt has both a gas engine and two electric motors—one primarily to power the wheels and a second to generate electricity from the gas engine—it is unlike any gas-electric hybrid on the road today: If charged sufficiently, it can operate continuously, at any speed, as an EV, without ever needing to switch on the gas engine. Of course, this raises a whole new set of questions, ranging from: “Won’t the fuel go bad at some point?” and “Isn’t it beneficial for longevity’s sake to start the engine once in a while?” to “Hey, boss, when can we start expensing our home electricity bills?”

This is but a glimpse into the Volt’s complexity and why, after six weeks of electric-only operation, the Volt will start to ask the driver via the instrument panel if it’s okay to switch on the gas engine for a bit to keep it fresh. And the Volt makes sure to burn through a tank of fuel each year to ensure it never gets stale. Plus, in order to extend the life of the very expensive battery—sources say it costs as much as $10,000; GM won’t comment—it uses only about 9 of its 16 kWh for propulsion and requires its own coolant circuit in order to heat or cool the 288 cells to keep them in the optimal temperature range (32° to 90°F). There’s yet another circuit to cool the electric motors. Things get even more complex in the powertrain, more so than we were initially led to believe [see download].

 

Behind the wheel, however, it all operates seamlessly. Hit the glowing blue start button, and the seven-inch LCD-screen instrument panel, like the one used for the standard navigation, comes to life. It presents an estimated electric-only range, a gas range, and a total of the two. To the right is a graphic that provides driving feedback; the Volt is operating most efficiently when the spinning, green ball of  leaves stays in the middle. Hit the gas too hard, and the ball elevates, shrinks, and turns yellow. Go for too much brake, and the ball does the opposite, slinging downward because energy that could have otherwise been recaptured regeneratively is being wasted. It’s a very straightforward and easy-to-follow setup. The center screen above the array of touch-sensitive controls on the dash keeps track of electrically and gas-driven miles separately, displays fuel economy (more on that later), and rates the efficiency of  your driving.

Whether or not the gas engine is running, the Volt always has an EV-like demeanor. Which is to say there’s almost no waiting—and no downshifting—as it responds swiftly to throttle inputs. Acceleration is one continuous ooze of thrust—sort-of CVT-like, only without the engine drone. In fact, although the Volt isn’t slow compared with its peers—its 9.2-second 0-to-60-mph time beats both the Leaf and the Toyota Prius by 0.8 second—it feels quicker than the numbers suggest because, off the line, no matter what the driver does, the electric motor’s 273 pound-feet of torque rolls out modestly and averts wheelspin. The immediacy you feel shows up better in the 3.7-second 30-to-50-mph time, which is just a couple of ticks slower than a V-6 Mazda 6.

There’s not much noise, either. In EV mode, the cabin is as quiet as a Lexus RX350’s at 70 mph, and even with the engine running, it matches the Prius at 72 dBA. The point at which the engine fires is barely discernible—the reconfiguring of the digital dash when it transitions is far more obvious. When the driver hammers the Volt in range-extending mode, the engine revs more assertively but is never harsh or intrusive.


Beyond its impressive powertrain, the Volt drives surprisingly well, with a reassuringly steady suspension. The electric power steering is light but direct on-center, adding weight in proportion to angle. It’s neither totally natural nor terribly off-putting. Ditto the regenerative brakes, which work well at moderate levels, though they’ll never match the feel of a good ol’ vacuum booster. At low speeds and during near-limit applications, the brakes can feel disconnected and very nonlinear.

Naturally, the Volt sports various mileage-extending features, including the anticipated wind-swept shape and a front apron to help aerodynamic efficiency. That said, its coefficient of drag is 0.29, worse than the far-more slippery Prius’s 0.25. The forged aluminum wheels wear low-rolling-resistance Goodyear Fuel Max tires, which squeal loudly as they approach the limit but are surprisingly capable, delivering a solid 0.83 g on the skidpad—same as the frisky Honda Accord. The stability control can’t be disabled, but it operates deftly so as not to intrude on smooth excursions to the limit, where the Volt is actually reasonably balanced.

Another interesting tidbit is an automatic seat-heater function. Warming the car’s cabin can be a significant energy draw—at times even more than powering the wheels—so the Volt will sometimes heat the seats instead of cranking the HVAC system to save power. And the Volt is the first vehicle to feature Bose’s new Energy Efficient Series sound system. The seven-speaker stereo uses amplifiers that rapidly switch on and off to conserve power rather than always-on linear amplifiers, and—combined with higher-grade neodymium magnets—the Bose system is both lighter and uses 50 percent less energy than before. But, most important, its clean and punchy sound quality is competitive even with that of cars costing far more.

Of course, pruning a few watts here and there can’t get around the fact that the 3755-pound Volt is definitely packing some extra weight. It’s some 575 pounds more than the Prius, 549 more than its Chevy Cruze platform-mate, and almost 400 more than the electric-only Leaf. Even though the 435-pound, five-and-a-half-foot-long, T-shaped battery pack lives under the cabin (that’s the reason why there’s no center rear seat), the Volt is surprisingly front-heavy, slightly more so than the Cruze, in fact. However, the battery pack contributes to the Volt’s two-inch-lower center of gravity compared with the Cruze.

Worried about the charging process? Don’t—it’s not the least bit intimidating. Most of us simply plugged the Volt’s cord into a 120-volt household outlet overnight. Ten hours later, it was fully charged. Cost: about $1.60. Also, the Volt can be programmed to delay charging based on a set schedule or electricity rates; doing so can be controlled and monitored via a smartphone application. Although installing a 240-volt system drops the 10 hours to just four, the Volt’s 120-volt charging time (unlike the 19 hours required to charge the Leaf on 120) seems reasonable enough that such a system isn’t absolutely necessary. Owners will probably want an additional charging cord, though, to prevent the constant fetching and stowing of the single, 120-volt unit from the cargo hold.


But what about fuel economy, the Volt’s raison d’être? Well, that requires a fair bit of explanation. And much is still undecided; GM officials wouldn’t venture any estimates, citing that they’re in nearly daily talks with the EPA as to what will be on the Volt’s window sticker when the car hits showrooms in December.

Here’s what we do know: GM’s recently revised electric-range claim is 25 to 50 miles, and we ended up in the low to middle of that band. Getting on the nearest highway and commuting with the 80-mph flow of traffic—basically the worst-case scenario—yielded 26 miles; a fairly spirited back-road loop netted 31; and a carefully modulated cruise below 60 mph pushed the figure into the upper 30s.

Following the EPA’s proposed direction for its 2012 fuel-economy labels [pictured below], we computed an energy-equivalent efficiency of the Volt during our 152 miles of EV operation. Even with a lot of aggressive driving, the result is still impressive: 74 MPGe.

But this number, too, requires a couple of caveats. First, we’re counting (as does the EPA) all the electricity used in the charging process—which has a fair amount of inefficiencies—not just what the vehicle deploys to the wheels. In our experience, using only standard-household 120-volt power, it took about 13.4 kWh of electricity to replenish the Volt’s 9 kWh of usable energy. Using a 240-volt setup instead is more efficient and would have boosted the mileage figure.

And these numbers also differ from the Volt’s fairly optimistic fuel-economy readout, which leaves the electrically driven miles out of the calculation entirely. Technically, the displayed number is accurate in that it is the “miles per gallon of gas,” but should electric miles really  be counted as infinite mpg?

Either way, one thing’s for sure: Operating an EV can be exceptionally cheap. Assuming 35 miles of electric range for the Volt yields a cost per mile of just 4.6 cents. That’s almost 40 percent less than that of a Volkswagen Golf TDI diesel getting 40 mpg and 24 percent cheaper than a Prius getting 45 mpg.
The economic picture is dimmer when operating the Volt using its gas engine. We averaged 35 mpg for our gas-powered miles and saw 33–34 mpg at a steady, near-80-mph cruise—not exactly spectacular compared with today’s hybrids. Then again, no one should buy a Volt if they plan to run it extensively in extended-range mode.


Is it cheap? New technology never is. Still, the Volt strikes us as the closest in concept to the winning formula of the Prius, albeit with the next generation of propulsion and the whole thing inverted. Nothing else has so successfully incorporated all of the key aspects of Toyota’s golden child—big fuel-economy numbers, a unique name and styling, and enough range and people and cargo space that it can be an only and everyday car. Those traits have enabled the sales of nearly 2 million Priuses worldwide since its 1997 debut. With the possible exception of a fairly cramped back seat and an undersized cargo hold, the Volt checks all the boxes, plus it outdrives the hybrid competition. This is without a doubt the most important new car since the advent of hybrids in the late ’90s, and GM has nailed it. Is this the handing off of the Prius’s very illustrious torch?

Meet The New Economy Labels
To go along with the coming surge of new-technology vehicles, the U.S. Environmental Protection Agency and the U.S. Department of Transportation are revising the fuel-economy labels for 2012 that are required on all new cars and light-duty trucks. But the new labels aren’t final yet; two designs were shown, and the definitive label won’t be ready in time for the 2011 Chevy Volt and Nissan Leaf.

Today’s EV sticker lists EPA city and highway efficiency in units of kWh/100 miles, which makes it pretty tough for a non-calculator-wielding consumer to compare economy at a glance with, say, a hybrid that’s rated in miles per gallon.
The proposals show that cars will be rated on a miles-per-gallon-equivalent (MPGe) scale, which converts alternative means of propulsion—such as electricity or natural gas—based on their energy content relative to that of gasoline (for example, 33.7 kWh = 1 gallon of gas). Vehicles with multiple operating modes, such as the Volt, will get separate ratings for each one. Another metric listed for battery-powered vehicles is the required recharging time, although the assumed power source isn’t given. The new labels also add two emissions scores: one for tailpipe CO2 emissions and another for other air pollutants. Some argue, however, that EVs should be penalized for CO2 emitted during the creation of the electricity they use.


Want simple? One of the proposals puts a prominent letter grade based on fuel economy and emissions at the top of the label. But is it really too much to ask the car-buying public to grasp the higher-is-better MPGe system? Plus, what makes for an “A” will no doubt shift as cars get more efficient, so the ratings likely won’t be comparable over time. We’d also like to see a cost-per-mile figure (instead of annual fuel cost), which would make it more obvious how long it will take to pay back the higher price of a hybrid or electric car.
But the biggest question remains: How will the ratings for a car such as the Volt be combined into a single number that’s used for the all-important Corporate Average Fuel-Economy (CAFE) standard, which automakers are required to meet?




2011 Chevrolet Volt  Spec's
Brakes
Brake Type Regenerative
Brake ABS System Four-Wheel
Brake ABS System (Second Line) N/A
Disc - Front (Yes or ) Yes
Disc - Rear (Yes or ) Yes
Front Brake Rotor Diam x Thickness 11.8 x -TBD- in
Rear Brake Rotor Diam x Thickness 11.5 x -TBD- in
Cargo Area Dimensions
Trunk Volume 10.6 ft³
Cooling System
Total Cooling System Capacity N/A qts
Electrical
Cold Cranking Amps @ 0° F (Primary) N/A
Maximum Alternator Capacity (amps) N/A
Engine
Engine Order Code LUU
Engine Type Electric/Gas I4
Displacement 1.4L/85
Fuel System Electronic Fuel Injection
SAE Net Horsepower @ RPM N/A
SAE Net Torque @ RPM N/A
Exterior Dimensions
Wheelbase 105.7 in
Length, Overall 177.1 in
Width, Max w/o mirrors 70.4 in
Height, Overall 56.6 in
Track Width, Front 61.2 in
Track Width, Rear 62.1 in
Min Ground Clearance N/A in
Liftover Height N/A in
Fuel Tank
Fuel Tank Capacity, Approx 9.3 gal
Aux Fuel Tank Capacity, Approx N/A gal
Interior Dimensions
Passenger Capacity 4
Passenger Volume 90.0 ft³
Front Head Room 37.8 in
Front Leg Room 42.0 in
Front Shoulder Room 56.5 in
Front Hip Room 53.7 in
Second Head Room 36.0 in
Second Leg Room 34.1 in
Second Shoulder Room 53.9 in
Second Hip Room 51.2 in
Mileage
EPA Fuel Economy Est - Hwy 40 MPG
Cruising Range - City 325.50 mi
EPA Fuel Economy Est - City 35 MPG
Fuel Economy Est-Combined 37 MPG
Cruising Range - Hwy 372.00 mi
EPA MPG Equivalent - City 95
EPA MPG Equivalent - Hwy 90
EPA MPG Equivalent - Combined 93
Battery Range 35 mi
Steering
Steering Type Electric Pwr
Steering Ratio (:1), Overall 15.4
Lock to Lock Turns (Steering) 2.8
Turning Diameter - Curb to Curb 36.0 ft
Turning Diameter - Wall to Wall N/A ft
Suspension
Suspension Type - Front MacPherson Strut
Suspension Type - Rear Compound Crank
Shock Absorber Diameter - Front N/A mm
Shock Absorber Diameter - Rear N/A mm
Tires
Front Tire Order Code RBB
Rear Tire Order Code RBB
Front Tire Size P215/55R17
Rear Tire Size P215/55R17
Trailering
Dead Weight Hitch - Max Trailer Wt. N/A lbs
Dead Weight Hitch - Max Tongue Wt. N/A lbs
Wt Distributing Hitch - Max Trailer Wt. N/A lbs
Wt Distributing Hitch - Max Tongue Wt. N/A lbs
Transmission
Drivetrain Front wheel drive
Trans Order Code MKA
Trans Type 1
Trans Description Cont. Automatic
Vehicle
EPA Classification Compact Cars
EPA Greenhouse Gas Score N/A
Weight Information
Base Curb Weight 3781 lbs
Wheels
Front Wheel Size 17 x 7.0 in
Rear Wheel Size 17 x 7.0 in
Front Wheel Material Aluminum
Rear Wheel Material Aluminum

1 comment:

  1. Beautiful car. If I will have money some day I will definitely go for this car. Its really amazing.

    ReplyDelete

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