Audi A5 e-tron quattro concept review

What - Audi A5 e-tron quattro concept
Where - Audi secret test facility, Sweden
Date - March 2011
Price - TBA
Available - TBA

Summary - The A5 2.0-TFSI e-tron quattro is still only at the concept stage but Audi are so excited with this hybrid they are talking about it actually going into production. We got an exclusive first drive and as you'll read, the idea is so simple it makes you wonder why no one thought of it sooner.

We like - performance and handling with low emissions and an average fuel consumption of 104mpg.
We don't like - Four-speed R-Tronic twin clutch gearbox. We may have to wait some time before it finally goes on sale.

Gallery: Audi A5 e-tron quattro concept

First impressions

There's nothing new about hybrids - think Toyota Prius and Honda Insight - and as worthy as they are, their appeal is limited mainly to the green credentials which they purport to deliver. Few, if any, really return the sort of performance and handling we've come to expect from a conventional car. And this is a big problem for carmakers if we, the paying public, are going to adopt this type of power as a true alternative.

Audi, in their wisdom, acknowledge that if they are to become a main player in the hybrid market then they need to offer a car which ticks more than just the eco-friendly box.

Step forward the A5 e-tron quattro. This is an inspired piece of high-tech machinery bundled-up under the skin of a specially prepared, lightweight bodied A5. To the untrained eye there seems to be little difference between this and a normal A5. Even the interior appears the same - albeit this one has more switchgear so the Audi boffins can monitor its every move.

So what makes this concept so special? Well, in simple terms, Audi has taken a bog-standard A5 2.0-litre TFSI quattro and removed the propshaft and, instead, have installed an electric engine to drive the rear axle. With the propshaft removed, the transmission tunnel becomes an ideal place for the bank of lithium-ion batteries and a specially developed four-speed R-Tronic twin-clutch gearbox.

Performance

A further electric motor has also been added just behind the TFSI engine, which when combined with the rear-mounted motor and petrol engine, produces 314bhp.

This ensures that the hybrid offers impressive performance - top speed is pegged at 142mph, but the 0-62mph sprint takes just 5.9 seconds, 0.6 seconds faster than the quickest 2.0-litre petrol A5 on sale now.

Ride and handling

The even better news is that the all-wheel-drive quattro system hardly notices the missing mechanical link between engine and rear axle. For most of the time just the front wheels are being driven, the electric motor in the rear only cuts in as a supportive measure.

The specially developed software is constantly working to manage which wheel requires more power and when it detects extra grip is needed it decides where the torque comes from - either the petrol engine or the electric motor, or both - and then distributes more torque. All this happens in less than a blink of an eye and without any type of driver intervention.

Where the development process seems to be lagging behind the rest of technology advancements of this car is with the four-speed R-Tronic transmission. It clunks its way up and down the cogs with little finesse and feels like very much what it is: a work-in-progress.

Putting these teething problems to one side (Audi have only been working on this car for 18 months which, in car terms, is like the first trimester of pregnancy) and the overall handling performs much like its non-hybrid stablemate. In fact, it's better than that, because the electro-hydraulically controlled suspension has been set up like a sports differential. The torque vectoring gives it an agility not seen before in a hybrid car.

Interior

By using an existing A5 as a donor vehicle for this project there are few surprises within the cabin. It remains that calm and well-laid-out place we've become accustomed to expect from Audi.

There are a few additional big red buttons which we were told "not to touch" as they are the master off/on switches for the two electric motors and the electromechanical rear brakes.

The multimedia infotainment system has also now been rewired to give a primary function as a readout monitor for the onboard computers. It shows which mode of power is being used, where the power is being sent and an LED display giving a precise state of energy remaining within the batteries' cells.

Of course, if this car ever comes to market these conceptional extras would be integrated within the interior or hidden away in the software of the engine management system.

Economy and safety

Whenever a car brakes, or accelerates, or suffers from any type of motion there is a build-up of energy which is known as kinetic energy. What Audi has done is to harness as much of this energy as possible and turn it back into electricity to feed the batteries.

This means the A5 e-tron can drive on electric power alone for around 30 miles, but this does cut the top speed to 62mph. The batteries are also recharged by the petrol engine, which is managed by an onboard computer, or can be topped up from a household plug. The batteries take around two hours to fully recharge.

But perhaps more impressive are Audi's claimed efficiency figures. Thanks to the hybrid powertrain, the A5 hybrid will return 104mpg while only emitting just 64g/km of C02 emissions.

The MSN Cars verdict

This may only be a concept, and it is still early on in its development, but it does show where Audi are going with their hybrid programme.

As much as they want to produce a car which offers the best of both worlds - electric and petrol - they also want to give the driver a car which can be enjoyed for more than its ability to wave an eco banner.

And if we are to believe Audi - and we have no reason not to - then we can expect to see the A5 e-tron go into full production within the next two years.

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