Posted Sep 25th 2012 11:57AM
The most innovative part of the Audi A3 E-Tron prototype isn't found under the front hood or in the battery compartment. Instead, one must sit in the driver's seat and move slightly to the side, then peer at the two smallish steering wheel-mounted paddle shifters.
On traditional internal combustion engine (ICE) vehicles, a quick tug on the left paddle shifts the transmission down one gear while the right is used for shifting the gearbox up. However, nearly all battery-electric vehicles (BEV) have but a single-speed transmission. Paddle shifters are completely unnecessary. The engineers at Audi, likely not wanting to leave gaping holes on the back of the trick sporty steering wheel, gave the two plastic flaps a new role – to control the intensiveness of regenerative braking.
It was a game-changing move.
Related GalleryAudi A3 e-tron: First Drive
Audi is no stranger to the electric movement. The automaker, part of the giant Volkswagen Group, has unveiled a handful of interesting EV concepts including the A1 E-Tron, R8 E-Tron and even the e-bike Wörthersee (Audi's "E-Tron" designation indicates that an advanced electrified powertrain with a plug-in capability is onboard). One of the latest additions to the automaker's development fleet is the A3 E-Tron, which is a fully functional road-going prototype.
We met the A3 E-Tron in Hollywood, plugged into a charging station at a parking garage. Aside from the insanely oversized graphics, red accents on the alloy wheels, California CARB access sticker on the rear quarter panels and some new badging, one would be hard pressed to tell this A3 from any one of the thousands already zooming around Southern California.
The combustion-free powerplant makes 134 hp and 199 lb-ft of torque
and the batteries hold 26.5 kWh of energy.
Yet opening the hood reveals the secret. While conventional ICE-powered A3s in North America feature either a gasoline-fed turbocharged 2.0-litre four-cylinder or a diesel-fed engine with the same displacement, the E-Tron is custom-fitted with an electric motor and a pair of lithium-ion battery packs. According to Audi, the combustion-free powerplant makes 134 horsepower and 199 pound-feet of torque and the batteries hold 26.5 kilowatt-hours of energy. That's enough power to hit 60 mph (96 km/h) in about 10 seconds and enough juice for about 90 miles (145 km) of travel. It is a bit slower than its siblings - but it doesn't burn one drop of fuel in the process.
A closer look impressed us with how well Audi has managed the packaging. The combustion A3 is known for being a roomy compact five-door with plenty of hatchback utility, and it was a pleasant surprise to find the automaker was able to shoehorn the entire BEV powertrain into the chassis without cutting into the passenger compartment. Not one bit. There was plenty of space for the motor and transmission in the engine compartment, but the engineers had their work cut out skillfully hiding the batteries in the center tunnel (normally reserved for the exhaust and all-wheel drive) and below the load floor in the trunk (there is a mobility kit replacing a spare tire). The charging port is behind what was previously the fuel filler door, on the right rear quarter panel.
The engineers had their work cut out skillfully hiding the batteries in the center tunnel and below the load floor in the trunk.
The driver interface also appeared to have emerged from the transformation mostly unscathed – until we started scrutinizing. The center console, with the exception of a few new buttons, remains mostly untouched. However, the primary instrument cluster is all new. Standard ICE gauges (e.g., tachometer and coolant temperature dials) have been replaced with a power meter and two battery level gauges directly over the small multifunction display. The US speedometer in our tester has been recalibrated down to a realistic 100 mph (the A3 E-Tron will only run 90 mph or 145 km/h flat out) from its normally graduated 160 mph. Other cabin systems have also been tweaked. The climate control has been altered to run in a more efficient mode, and the vehicle's trip computer has been reprogrammed for BEV duty.
Combustion engines are heavy, but batteries are even heavier. Audi says the lithium-ion packs add about 400 pounds of mass, bringing the A3 E-Tron's curb weight to about 3,800 pounds (1,724 kg). Suspension upgrades counter the additional sprung mass while the braking system has been reconfigured with an energy recovery system (battery-powered vehicles use regenerative braking to recapture some of the energy wasted during slowing or stopping). Lastly, the rack-and-pinion steering, which is hydraulically assisted on the second-generation A3, has been replaced with an all-electric system.
A twist of the key brought the A3 E-Tron to life. Mirroring the powertrain response of the Tesla Model S, but unlike most other BEVs on the market, there is no "creep," a term frequently used with automatic transmission-equipped combustion-powered vehicles when they move forward slowly when in gear. Audi says creep wastes electricity, so the engineers programmed it so the operator must deliberately apply pressure to the accelerator to move the E-Tron forward. The low speed throttle calibration is good – we could crawl better than we normally creep.
Audi says the lithium-ion packs add about 400 pounds (181 kg) of mass, bringing the A3 E-Tron's curb weight to about 3,800 pounds (1,724 kg).
After limitless fuel economy, torque is the other main selling point of electric propulsion. The A3 E-Tron delivers in that category as it moved smartly off the line from a standstill. The engineers have put a three-mode switch on the center console to give the driver an option of choosing one of several driving modes (Efficient, Normal or Sport). Efficient was borderline lethargic while Sport seemed uncharacteristic for the BEV mission. We finally settled on Normal, as it felt about right for our low-performance city driving conditions.
It won't set any land speed records, but after half an hour we were convinced that the A3 E-Tron rode better than any other A3 on the market, period. The additional weight carried by the electric model, combined with the proper suspension calibration, meant it felt solid over even the roughest pavement. There was no bottoming out, harsh impacts or wallowing either. We cruised up Sunset and down Hollywood Boulevard very comfortably. And silently.
But the real game-changer, the visionary moment, occurred when we starting playing around with those steering wheel-mounted paddle shifters. As mentioned, all BEVs have regenerative braking, which is felt as drag on the vehicle when it is rolling. The A3 E-Tron takes things one leap further by allowing the driver to vary regenerative intensity. While not the only BEV that offers varying levels of regen intensity, it is the first that puts the controls at your fingertips like this. It may sound superfluous, but it works amazingly well as it replicates the physical attributes of a transmission downshifting.
Eureka! Audi has made the BEV fun to drive.
Bring the A3 E-Tron up to 50 mph (80 km/h) and pull the right paddle shifter a few times. With the throttle off, the hatchback will glide as if it is in Neutral. Give the left paddle a tug or two and it feels as if a six-speed manual was dropped into third gear. Pull it again and it replicates the higher drag of second gear. Not only does this increase the amount of energy being recycled, but it is amusingly enjoyable. Eureka! Audi has made the BEV fun to drive.
After some time behind the wheel, we were certain that Audi's A3 E-Tron was infinitely more engaging to drive than Honda's Fit EV or Toyota's RAV4 EV, and much more affordable than anything Tesla is offering. But don't march down to your Audi retailer with cheque in hand just yet. As mentioned, this vehicle is a prototype. Nobody outside Audi is driving one of the dozen or so E-Trons currently in North American circulation.
Don't march down to your Audi retailer with cheque in hand just yet.
Things will change for the 2014 model year. That's when Audi is likely to introduce the third-generation A3 to North America. Variants of the all-new platform (possibly now including a sedan) are expected to contain gasoline- and diesel-powered models, and, owing its existence to the research and development work labored by this A3 E-Tron BEV prototype, the automaker's first A3 plug-in hybrid (PHEV).
Let's hope those fantastic paddle shifters make the cut.
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