Tuesday, September 4, 2012

Nissan Leaf



By Larry E. Hall






Nissan has promoted the 2011 Leaf as “the world’s first affordable, zero-emission car.” That chorus was picked up and the little electric car became a media star. It garnered awards such as the 2011 World Car of the Year and 2011 European Car of the Year. In 2011, it was also the first electric vehicle to be included in Wards’s prestigious Top 10 engine list. Not only did Leaf usher in a new beginning of zero-emissions motoring, it also offered a sensible four-door hatchback body style and a pleasant driving experience.


Now in its sophomore year, Nissan has added standard features to the 2012 Leaf. The base SV now comes standard with heated front and rear seats, heated steering wheel, heated exterior mirrors and a battery heater. The SL model adds a standard DC quick-charging port. The upgrades come at a price, however. The 2012 SV starts at $35,200, an increase of $2,420, while the SL is priced starting at $37,250, a bump of $3,530.


However, once a $7,500 federal tax credit is factored in (for those who are eligible, and some states offer additional credits as well), the 2012 Nissan Leaf’s pricing becomes more affordable.

Drivetrain



The 2012 Nissan Leaf is powered by a 24 kilowatt-hour lithium-ion battery pack which generates power output of more than 90 kw, while its AC synchronous electric motor that drives the front wheels delivers 107 horsepower (80 kw) and 207 pounds-feet of torque. (Think of torque as the force that produces acceleration, horsepower as the energy that sustains momentum.) The drive motor and control system are placed under the hood, where you would expect to find an engine.


The drivetrain is completed by a single speed reducer type transmission. There are no clutches, gears or a torque converter like found on a standard automatic transmission. There are two forward operating drive modes: Drive and Eco. Drive provides instant acceleration that increases quite quickly. Eco extends the driving range by limiting acceleration and reducing power to the climate control system. It also provides additional brake regeneration, causing the car to decelerate more rapidly, but also adding electrons to the battery.

The Battery



Weighing about 660 pounds, the battery is located under the floor pan directly beneath the front and rear rows of seats, which keeps the weight low and centered for better on-road stability and handling. The proprietary battery uses lithium manganese technology in the cells, a material that Nissan says was chosen for its resistance to thermal runaway. Four laminated flat, license-plate-style cells make up a module, with 48 modules arranged in three stacks.


Nissan engineers allow 95 percent of the Leaf’s energy storage to be used. This stands in sharp contrast to the 2013 Chevrolet Volt, which only ever uses 10.8 kilowatt-hour of its 16- kwh pack. In most conventional hybrids, the battery is never charged or discharged beyond 60 or 70 percent.


The Leaf is an advanced, practical, affordable and a usable battery-powered car yet, it still is plagued with two issues that have dogged electric cars for more than a century: driving range and recharging time.


Nissan advertises that the Leaf can travel 100 miles on a fully charged battery. But that is based on U.S. Environmental Protection Agency (EPA) LA4 City cycle conducted in laboratory tests. The official EPA electric driving range is 73 miles. While both numbers are achievable – depending on driver habits, speed, terrain, temperature, and battery age – the limited cruising distance is great for a very small number of consumers, but the Leaf is not a breakthrough car that makes electric vehicles practical for the majority of car owners.


(Note: To help consumers compare “fuel efficiency” for a gasoline or diesel cars to electrical energy consumption by electric cars, the EPA has developed a formula called miles per gallon equivalent (MPGe). Nissan’s Leaf has an MPGe rating of 106 City/92 Highway and 99 Combined.)


As for charging time, it varies depending on what kind of charging you employ. At the longest, it can take up to 21 hours using a standard 120-volt household current – and this is not very practical for most daily drivers. It’s therefore advisable to install a 240-volt charging station that can recharge a fully depleted Leaf battery in seven hours, with partial charges taking less time. Unit costs start at under $1,000, can be professionally installed for somewhere up to $2,000 for an easy install but can be as high as $5,000 to $7,000 if major electrical work is required. Having your house checked by a qualified electrician might be advisable beforehand to determine what your situation would actually require.


The Leaf’s battery can also be “quick charged” at locations offering industrial-level DC Fast Chargers. They can recharge from 20 to 80 percent of capacity in about half an hour via a quick-charge port that is now standard on the SL model. DC Fast Charging stations have been slow to roll out but have gained momentum of late. Nissan cautions, however, that using quick charging frequently can shorten battery life.


Of note, HybridCars.com has reported that in late July some Leaf owners – especially those in Arizona and Texas, two of the hottest and first states to get Leafs – have complained about premature battery capacity losses in excess of 15 percent. They believe it is due to high temperatures, and at this writing are waiting further response from Nissan.


The Leaf’s battery pack is “passively” air cooled, while other automakers, like General Motors, Tesla, Ford and Coda employ “active” systems to distribute a liquid or air to maintain an optimal range of temperature.

Styling



Slightly larger than a Nissan Versa, the Leaf is distinctive enough to set it apart from other hatchback models, but nothing about it shouts “green.” The styling is somewhat polarizing, eliciting comments from, “It’s a stylish, innovative looking glass into the future of the automobile,” to, “It looks like a platypus.” Built on a dedicated platform, it’s not an electrified version of a gasoline powered car like the Ford Focus Electric, it’s an exclusive model all its own.


The Leaf’s exterior is distinguished by a noticeable low hood flanked by two upslanted V-shaped headlights that split and redirect airflow away from the door mirrors, reducing wind noise and drag. With no radiator required to cool a nonexistent gas engine, the nose is grille-free, replaced by a door that opens for access to its charging ports.


A prominent character line flows from the top of the front fender upward towards bulging rear fender wells. In the rear, slim, vertical LED taillights are mounted high and extend downwards following the shape of the hatch door. Designers sprinkled just the right amount of chrome on door handles and a horizontal bar below the hood.

The Cabin And Features



Despite the small platform, the Leaf’s cabin feels spacious and airy, courtesy of an arched roof and a 106.3-inch wheelbase. Wheelbase is the distance between the front and rear axles and helps determine how much space a vehicle can devote to the passenger compartment.


The dash has a simple, clean design with a prominent center stack that features a seven-inch touchscreen, which controls the standard navigation system as well as showing a variety of things like energy efficiency readouts and driving range. In front of the driver, a two-tier instrument cluster is similar to that found in the Honda Insight. The top display includes the speedometer, time, outside temperature and an Eco indicator. The lower display houses the power meter, battery temperature, battery charge level, remaining energy gauge and a gauge that estimates the amount of remaining range in miles still available, based on the charge of the battery. The mileage remaining numbers shown are so overly optimistic or overly pessimistic that some Leaf owners have named the gauge “Guess-O-Meter.”


Quality of plastic materials is on par for the compact class and assembly construction is superb. Seat fabric and other interior pieces are made with partially recycled materials. Front seats are a nice balance between comfort and support. The driver’s seat is manually adjusted for height and the steering wheel tilts but surprisingly doesn’t telescope.


Front head-and legroom is generous, rear seat accommodations a little less so. Rear seats are split 60/40, and fold to expand the 14.5 cubic foot of cargo space, but there’s a step up in the load floor. A low stance makes it easy for little ones to climb in and out of the Leaf without help. There’s plenty of room for two car or booster seats but the latch anchors are difficult to dig out of the stiff seat cushions.


The Nissan Leaf is very well equipped with standard features. In addition to the 2012 upgrades mentioned earlier, the entry SV model comes with keyless ignition/entry, full power accessories, cruise control, steering wheel audio controls, automatic climate control and navigation system. Also included are an advanced trip computer, an AM/FM/CD audio system, iPod/USB audio interface, satellite radio and Bluetooth cell-phone connection.


Stepping up to the SL adds a rearview camera, automatic headlights, fog lights, the quick-charge port and a spoiler-mounted solar panel that trickle charges the conventional 12-volt battery, used to power accessories such as the radio.


There are a lot of gee-whiz features like the navi system’s ability to download custom routes from Google Maps, darken parts of the map that are out of range for the current charge and remembers every place you’ve plugged into. Also, the smart phone app connects to the Leaf in seconds and lets you check state of charge, schedule battery charging times as well as pre-warm or cool the cabin, plus more.

Driving The Leaf



Car and Driver said about the Leaf, “Range aside, the Leaf seems like a normal car.” HybridCars.com staff couldn’t agree more. We have driven several Leafs (Leaves?) on a variety of roads and a variety of distances and our notes always said, “It’s just like a normal car.” It requires no adjustments or changes from how you would operate a gas-powered car, which is what Nissan intended.


With a stout 207 pounds-feet of torque available from the electric motor the moment the go pedal is engaged, the Leaf’s acceleration is quite robust, reaching 60 mph from a stop in about nine seconds. The rate of speed begins to decrease around 45 mph, meaning you need to plan passes at highway speeds. The cabin is commendably quiet up to 60-65 mph, then wind and road noise become noticeable. While top speed is limited to 90 mph, highway driving quickly drains the battery.


The Leaf has a smooth, well-damped ride in urban conditions and on the highway exhibits the solidity of a larger car. Like most small cars the rear independent suspension is a twist-beam design, which limits its effectiveness in the corners. There is little body lean, but the ultra-low-rolling-resistance tires give up grip quickly.


Electrically assisted, the steering feel is natural and contributes to a generally rewarding drive. Kudos to the engineers who designed and tuned the regenerative brake system; brake pedal feel is firm and braking can be modulated, something that can’t be said about other regen brake systems.


While how many miles can be driven on a fully charged battery is most often talked about, another key metric is miles-per-kilowatt-hour efficiency. In our many drives we have registered as low as 3.4 miles/kwh, about 60 miles when driving really stupid with the air conditioner blasting, to as high as 4.27 miles/kwh, around 94 miles driving ultra conservatively. In other words, how you drive the Leaf plays a major role in how far you can travel on a fully charged battery.

Economics



Evaluating the Nissan Leaf can be looked at in two ways: $35,200 is way too many greenbacks for a car that can only travel 70 to maybe 100 miles or, the price is a bargain when you consider it severs the connection between the oil pipeline and your car plus, it produces zero emissions.


If you lean towards the second viewpoint, cost of ownership might be a factor in the buying decision. NADA Guides calculates the five-year cost of ownership is $38,647, which is very close to Motor Trend Magazine’s figure of $38,813. Motor Trend also gives the Leaf an “Excellent” value rating. Using Green Car Calculator to compare the Leaf with the similar size Nissan Versa, the Leaf five year ownership cost is $32,166 compared to the Versa’s $26,693. An additional viewpoint – and more info on going electric – can also be had from the advocacy group,
Plug In America.


Leaf has few competitors, including the 2012 Mitsubishi I-MiEV that is smaller than the Leaf, capable of 62 miles per charge and starts at $29,125. Ford’s 2013 Focus Electric is Leaf’s closest comparable EV with a starting price of $39,200. There’s also the Tesla Model S, a sport sedan priced from $49,900.


The Nissan Leaf may be the “the world’s first affordable, zero-emission car,” but it won’t restore the ozone layer by itself. While nudging us in the right direction, it also helps reduce oil dependence not to mention need to stop at the gas station and some scheduled maintenance required for internal combustion vehicles.


The Leaf is therefore a highly qualified decision weighing factors consumers did not have to consider before the new vanguard of electric vehicles began a couple years ago. Some benefits are obvious, and others may not be as apparent, but depending on your hot buttons, the value can be just as real, and in some cases, only possible for this kind of car.


Prices are manufacturer suggested retail price (MSRP) at time of publication and do not include destination charges, taxes or licensing.

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