Though we knew Audi was planning on showing an A1 and A8 Hybrid at the Geneva auto show, we're just now getting the full details on the two cars.
The Audi A1 e-tron is the company's latest EV concept and it's first extended-range vehicle. Though powered only by its electric motor, the A1 e-tron carries with it a single-rotor Wankel rotary engine as a generator and range-extender. Together with the lithium-ion battery pack mounted under the floor (for optimal weight distribution), they give the A1 e-tron a total range of 124 miles with 31 of those miles powered by the battery only.
The A1 e-tron in essence retrofits a new A1 with an electric drivetrain and backup generator, but there's more to it than that. The 102-horsepower, 75 kW electric motor is mounted under the hood in place of a standard internal combustion engine and typically runs at 61 horsepower, or 45 kW, with 110 pound-feet of torque. Stab the throttle, though, and it will give you short bursts of the full 102 horsepower and 177 pound-feet of torque. That's enough for a zero to 62 mph sprint in 10.2 seconds and a top speed of over 80 mph. Power finds the ground via a single-speed gearbox.
Once you've depleted the battery, which is mounted in the center tunnel and under the rear seats, the 254 cc rotary engine mounted in the rear below the luggage compartment kicks on and generates 15 kW of power running at a constant 5,000 rpm, or you can turn it on yourself at any time with a button on the dash. Audi says the whole generator system, save for the three gallon gas tank, weighs just 154 pounds, while the 380-volt battery pack weighs just 331 pounds. In all, this adds roughly 300 pounds to the A1's svelte frame, but this car is no porker. It still weighs in at only 2,624 pounds, according to Audi.
More importantly, Audi says that the battery pack can be recharged in as little as three hours on a 380-volt circuit and all together, the drivetrain returns 124 mpg, all while maintaining the sporty characteristics of the standard A1. The plug can be found hiding behind the four rings on the grille and is accompanied by a power gauge to let you know the charge state immediately.
Going to electrical power as the primary source of motivation requires compromise. The climate control system is now electric and acts as a heat pump to regulate both cabin and battery temperatures. Cooling for the battery pack and generator are on a separate, proprietary system that Audi won't tell us about yet. Brake boost is now provided by an on-demand electric vacuum pump and the braking is done by wire, not by hydraulics. The electric motor also acts as a generator under braking to recover energy. Power steering is also supplied on-demand via an electro-mechanical system.
As you may have guessed, the A1 e-tron is still meant to be a city car, not a long-hauler. Audi has already promise that a limited-production e-tron will be coming in 2012 and depending on its success as well as that of the upcoming Chevrolet Volt, it's quite possible an A1 e-tron could see production someday soon.
The A8 Hybrid, meanwhile, is more of a traditional hybrid. It combines Audi's 211-horsepower 2.0-liter, direct-injected, turbocharged four-cylinder with its 258 pound-feet of torque with a 33 kW, 45-horsepower electric motor that makes 156 pound-feet of torque. Joined by a wet clutch, the two motors put their power to the ground through Audi's eight-speed automatic transmission and the front wheels.
Audi says that the electric motor can propel the A8 Hybrid up to 40 mph without any help from the gasoline engine. Jump on the gas, though, and the computer unleashes the full force of the drivetrain and its 245 horsepower and 354 pound-feet of torque.
Providing power for the electric motor is a lithium-ion battery pack mounted in the rear of the car that Audi says is both lighter and more powerful than other batteries on the market. Despite its location, Audi says the A8 Hybrid still offers 14 cubic-feet of trunk space. Like the A1 e-tron, the A8 Hybrid uses an on-demand electric vacuum pump to boost the hydraulic brakes, an electric power steering rack and an all-electric climate control system.
Adding all this hybrid technology has packed only 100 pounds onto the A8's curb weight according to Audi. With 4,156 pounds to carry around, the A8 Hybrid will hit 62 mph in a reasonable 7.6 seconds and will top 145 mph. More importantly, Audi says it will get 38 mpg combined. Official figures for a standard A8 aren't out yet, but its fuel economy is likely to be significantly worse.
Though the A8 Hybrid is only a concept at the moment, Audi is quick to point out it's a near-production car. What's more, the hybrid technology here is already developed and will debut soon on the upcoming Q5 Hybrid SUV. Will the A8 Hybrid see production? Audi hasn't said for sure yet, but it's a safe bet.