First drive of Audi’s electric R8, A1
Of late, a number of manufacturers have revealed their respective plans to reduce carbon dioxide emissions and the footprint the automobile leaves in its wake. Audi is the latest company to map out its future. The new direction includes hybrids, plug-in hybrids and all-electric vehicles — it all falls under an initiative called e-tron (in Audi speak, e-tron is to electromobility what quattro is to all-wheel drive). At the Electromobility workshop, Audi had a number of rides available for test. The list included an A1 e-tron range- extended compact and the stunning all-electric R8 e-tron. The latter is one seriously electrifying drive and a world-class sports car in its own right.
Based on the R8’s skeletal platform, the e-tron features a large lithium-ion battery (mounted behind the passengers for optimal balance), all the needed power electronics and four electric motors (two front, two rear). The latter ensures that the electric version retains Audi’s preferred all-wheel-drive setup. However, the proactive nature of the e-quattro system means the power can be directed to the wheel(s) best able to put torque to tarmac, and it can torque vector by driving the outside rear motor faster then the others.
Even with all of this electronic trickery aboard, the R8 e-tron tips the scales at just 1,600 kilograms, which is about the same as the R8 V10 and its monster 5.2-litre V10 gasoline engine.
The main battery has a total energy content of 53-kilowatt hours; however, the usable portion is limited to 42.4 kWh in the interest of service life (never fully recharging or depleting the battery extends its usable life enormously). Recharging the main battery takes eight hours when using a 220-volt outlet — a special fast-charge system cuts the charge time to just 2.5 hours. From a practical perspective, the R8 e-tron boasts a driving range of approximately 250 kilometres on a full charge and the ongoing assistance of regenerative braking. The net result is a riotous automobile that’s quite unlike anything I have driven. The four motors combine to deliver 308 horsepower, which is not too shabby.
What makes the R8 e-tron such an electrifying ride, however, is the torque component. The electric motors generate a combined total of 442.5 pound-feet of torque from Rev One. The mind-blowing part is that after going through the gearboxes, the R8 e-tron launches off the line with a combined total of 3,319 lb-ft of torque! To put that into perspective, the R8 V10 makes almost the same amount of torque after the gearbox and final drive, but not until 6,500 rpm.
Obviously, having this much twisting power brings scorching performance. The R8 e-tron runs to 100 kilometres an hour in 4.8 seconds and it accomplishes the 60-to-120-km/h dash in the same time as most self-respecting sports cars take to get from 80 to 120 km/h. Trop the go pedal at 60 km/h and the speedometer’s needle flashes through 120 km/h in just 4.1 seconds as it races toward its electronically limited top speed of 200 km/h. The speed is capped because of the tremendous draw higher speeds place on the battery.
As impressive as the phenomenal torque plateau is, the noise this car makes is even more so: It’s basically silent. In my years covering the automotive beat, I have driven some seriously radical cars — the R8 e-tron takes the biscuit!
The A1 e-tron is an all- electric vehicle for the first 50 km. Beyond that distance, it uses a gasoline-powered range extender. It is, in terms of its operation, similar to the Chevrolet Volt in that there is no direct connection between the engine and wheels. The 254-cc engine drives a 15-kW generator, which supplies the electricity to charge the battery and/or power the electric motor. This strategy delivers a driving range of 250 km (from a 12-litre gas tank!) and a fuel consumption rate of just 1.9 L/100 km. The 12-kWh lithium-ion battery, which operates at 270 volts, can be charged from a 220-volt outlet in less than three hours. The electric motor, which is mounted low and up front, delivers a continuous output of 61 hp and 111 lb-ft of torque. However, it can deliver a peak of 102 hp and 177 lb-ft when the driver hammers the go pedal. This gives the four-seat A1 e-tron the wherewithal to run to 100 km/h in 10.2 seconds and on up to a top speed of 130 km/h.
The drive proved just how integrated the extended-range system is in operation. The transition between all-electric and extended-range modes is completely seamless. In fact, the only thing that gives the game away is a small “range” light that illuminates within the instrumentation. The Wankel (rotary) engine is also surprisingly quiet (from the driver’s seat, it is virtually silent) and it’s impeccably smooth in spite of the fact it spins away at 5,000 rpm whenever it comes to life.
Finally, the A1 e-tron’s instrumentation is to die for — the satin-silver dials and a pictogram show the driver exactly what’s going on at any given time. The A1 e-tron is currently undergoing fleet testing before series production, while the R8 e-tron is set to go into production in late 2012.
If this is the future of the all-electric automobile, I’m an unabashed fan.
Photograph by: Audi, handout