what fuel will we be

What fuel will we beusing in the future?

What will tomorrow’sengines look like?

What cars will be on the roads of thefuture?It is of existential importance to Audi to find answers to these questions. And this quest repeatedly demandsfresh inspiration. “Progressive Performance” is the strategy adopted by Audi to promote the responsible use of our environment and resources. Whether investigatinginnovative fuels, developing fuel-saving engines orspecifically trimming weight off designs, Audi’s engineersand partners are exploring every avenue in order to rise tothe challenges of the future, today. The vast potential thatresides in the synergy of such technological innovationsprovides a glimpse of the future.

Meadows shaping the future: they can supplythe biomass that provides the basic material forthe production of high-grade diesel fuel.

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11AUDI 2006 ANNUAL REPORT

Audi, Volkswagen and Shell are collaborating on the development of synthetic fuels. Synthetic fuelsare paving the way for new engine concepts that use fuel much more efficiently and further reduceexhaust emissions. Shell is carrying out research work into the fuels of the future in a laboratory in the port of Hamburg. Text Markus Gärtner // Photos Jens Neumann

Shell PAE lab

Optimising the formula

Dr. Wolfgang Warnecke,who is responsible for Shell’s worldwide fueldevelopment activities,scrutinises the colourlessGTL diesel SynFuel.

12 AUDI 2006 ANNUAL REPORT

PROGRESSIVE PERFORMANCE: POWERED BY SYNFUEL


S hell Global Solutions’ Products,Applications and Developmentlab (or PAE for short) is home to

180 researchers who work in close coor-dination with car companies, shippingfirms and even the Formula 1 world tooptimise fuels. The PAE lab is where thefuel for Michael Schumacher’s racingcars was created. And it also formulatedthe special diesel fuel which the AudiR10 TDI used to win the Le Mans 24Hours and the American Le Mans Seriesat the very first attempt last year.

But the PAE lab concerns itself withmore than just high revs. It is preparingthe way for an even more environmen-tally friendly future. One of the stan-dard-bearers of this advance is the gas-to-liquid (GTL) fuel which is ob-tained by converting natural gas intosynthesis gas with the aid of oxygenand steam, and then into liquid hydro-carbon. High-grade fuel for diesel en-gines is then derived from this by frac-tional distillation. The colourless andodourless liquid is sulphur-free. It con-tains neither aromatic compounds nororganic nitrogen.

Marked reduction in pollutantsThe synthetic fuel significantly reducespollutant emissions, assures Dr. Wolf-gang Warnecke, Director of the PAE lab.Warnecke is responsible for Shell’sworldwide fuel development activities.The engine and fuel expert refuses to bedrawn on precisely how low-pollution it is. Because reducing pollutants de-pends very much on making exhaustemissions treatment more effective andcombustion methods more efficient.Such factors are determined by enginedevelopers at car companies ratherthan fuel experts.

SynFuelSynthetic fuels, or SynFuels, are produced

from synthesis gas obtained either from

natural gas or from biomass. If natural gas is

the raw material, this is referred to as a gas-

to-liquid (GTL) process, and if biomass is the

basis, it is a biomass-to-liquid (BTL) process.

If obtained from natural gas, the fuel is called

SynFuel and if from biomass, it is referred to

as SunFuel.

But Warnecke is optimistic about themanufacturers. “When many of us start-ed studying Engineering,” he recalls, “itwas the case that all manner of conceptswere being created to optimise engines,but that the fuel was an off-the-shelfproduct with hard-and-fast specifica-tions. The position now is that enginesare being developed to suit the fuels. Thefuel has become one of the key para-meters.” In a nutshell, the fuel researchersfrom Shell are increasingly encounteringinnovations at the hardware end in theirpartnership with Audi and Volkswagen.Fuel and engine development activitiesare proving mutually beneficial.

GTL is still a relatively new process.Shell has been producing SynFuel inMalaysia for the past few years, at therate of 14,700 barrels per day. Two yearsago, GTL fuel was launched at the group’sEuropean filling stations under the nameof V-Power diesel. Others are followingsuit: the South African energy groupSasol is opening a second industrialplant in Qatar in the first half of 2007.

Shell intends to erect a large-scaleplant, again in the Emirate of Qatar, >>

In the production of high-grade diesel fuel

from biomass (BTL), plants are completely

processed.

Markus Gärtner, 46, has been re-

porting from Vancouver as an inde-

pendent correspondent since 2004.

He was previously Bavaria reporter

for the Deutschlandfunk radio station,

Frankfurt correspondent of the ARD television

station, Southeast Asia correspondent for

Die Welt and Handelsblatt’s man in China for

six years.

Top: Dr. Warnecke regards the production of diesel fromnatural gas or biomass as an intermediate step alongthe road to the hydrogen age. Bottom: For well over twoyears now, drivers have beenenjoying the benefits of ShellV-Power, the fuel producedby the gas-to-liquid (GTL)process, for example at theWorld Economic Forum 2007in Davos.

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Alternative: bio-ethanolThe Canadian biotech company Iogen, based

in Ottawa, operates the only demonstration

plant in the world that produces cellulosic

ethanol from agricultural waste, such as

wheat stalks, maize cobs and straw. Enzymes

break down the residue from harvesting into

a sugary mass from which alcohol is distilled.

As it comprises waste products, the environ-

mental balance is virtually neutral. The yield

per hectare of land is moreover much higher

than for conventional ethanol. 340 litres of

ethanol are obtained from every tonne of

cellulose. The cost is currently around 36 US

cents per litre. Iogen is planning to build the

world’s first large-scale ethanol production

plant in 2007, probably in the US state of

Idaho. The US government is calling for cellu-

losic ethanol to be available at filling stations

at competitive prices within six years. It is

already being mixed with conventional petrol.

Expectations of the Iogen process are so high

that the investment bank Goldman Sachs

invested in the company in May 2006. At the

start of 2006 the Volkswagen Group agreed a

partnership with Iogen to pioneer the tech-

nology for cellulosic ethanol and examine the

scope for building an industrial-scale plant

in Germany. The head of the company is

engineer Brian Foody. Foody has developed

the enzyme manufacturer into one of the

leading players in the highly promising

market for biofuels.

by the end of the decade. It will bearound ten times the size of theMalaysian plant, turning out 140,000barrels per day. The International EnergyAgency (IEA) predicts daily productionof GTL fuel to reach 2.4 million barrelsby 2030. To place this in its context,consumption is currently running ataround 90 million barrels of mineral oilper day.

“It is not yet clear how many plantsthere will be in the next ten years andhow available they will be,” admitsWarnecke. “By 2015, GTL will accountfor a mere three or four percent of theentire amount of fuel refined,” declaresWarnecke, an engine designer by back-ground, confirming the IEA forecast.That is why other alternative fuel sourcesalso need to be tapped, such as second-generation biofuels (biomass-to-liquidBTL) which, unlike first-generation bio-fuels – where only the oily fruit is used –use the entire plant or even green waste.

BTL fuels have the advantage thattheir carbon dioxide balance is virtuallyneutral. They can reduce CO2 emissionsby over 90 percent compared with fuelproduced from mineral oil.

This is why Shell has invested in thebiofuel manufacturers CHOREN andIogen. “We want to provide assistanceof both a financial and technologicalnature in promoting methods such asthose being pioneered by CHOREN andIogen, and we want to use these fuels.Iogen is the leading player for petrolsubstitutes, and CHOREN for diesel sub-stitutes,” explains Wolfgang Warnecke.

GTL as an interim solutionGTL technology is of course beingpursued as a top priority. According toWarnecke, the synthetic diesel is eco-nomical to produce even at a crude oilprice of 25 US dollars a barrel. GTL isnevertheless unable to keep pace withconventional fuels in price terms. But itdoes have a huge strategic advantage:according to current estimates, theworld’s gas reserves will last 70 years –30 years more than our crude oil re-serves. Sufficient time, therefore, to use biofuels as a wise interim solutionuntil the hydrogen age has properlydawned.

“Hydrogen will definitely arrive, butnot to any substantial degree over thenext 20–25 years,” predicts Warnecke.“So we will need an interim solution totide us over when making the transitionfrom carbon to hydrogen: syntheticfuels which can increasingly be addedto present-day fuels.”

The breakthrough will depend on a variety of factorsSuperior availability and the much low-er emissions alone will, however, notsuffice to help fuels such as GTL dieselmake a breakthrough as long as they areunable to compete in price terms. InGermany, around 70 percent of dieselfuel is used by trucks and buses which,Warnecke warns, are “extremely cost-sensitive”.

The EU is aiming to boost biofuelsfrom a current two percent to six per-cent of entire fuel consumption by 2010.But the legislative body has not yet tak-en account of all the benefits of modernbiofuels in calculating the tax incen-tives: “The EU Commission – which laysdown the standards – really needs totake account of how the fuel is pro-duced as well. Focusing solely on whatcomes out of the exhaust pipe is notenough. That’s why the German govern-ment is now providing tax incentives for fuel obtained from sustainable rawmaterials,” explains Warnecke.

Shell’s senior fuel developer is allud-ing here to the complex processes thatShell is developing together with itspartners Iogen and CHOREN. Consider-able investment will still be needed be-fore the first plants are able to go intoproduction on a large scale.

The Audi R10 TDI, running on top-quality fuel from Malaysia, provedunbeatable on the Le Mans race track in 2006. The world’s largestnatural gas processing plant is located in Bintulu. Text William Whey

GTL technology

From terra firma to top of the podium

PROGRESSIVE PERFORMANCE: POWERED BY SYNFUEL


S hell’s gas-to-liquid (GTL) tech-nology is instrumental in pro-ducing diesel fuel that is not

only more powerful, but efficient andenvironmentally friendly at the sametime. The ability of Shell to turn naturalgas into diesel fuel with 50 percent bet-ter combustion quality than normal re-finery diesel is a marvel in its own right.The engineers at Audi took advantage ofthis virtually sulphur-free diesel andharnessed maximum potential from itto power the Audi R10 TDI to victory atLe Mans 2006.

From terra firma …Sarawak, East Malaysia – miles of pris-tine white, sandy beaches, cloaked in agreen blanket of rain forests. Thenthere’s Bintulu – a sleepy coastal fishingand timber trading town. The idyllicsetting belies its world status. The natu-ral gas reserves just off the shores ofBintulu have transformed this terrafirma into the world’s single largest nat-ural gas processing plant.

However, the development of Bintuluinto a major natural gas centre has notaffected the soul of the place. This isstill a pretty much laid-back town thatexhibits the rustic feel of the 70s. Thehustle and bustle of the city slows to astrolling pace at dusk. Time in Bintulujust ticks away – a minute at a time.“Calm, nonchalant and comfortable” –that’s the motto of the locals. Theevening fades into pitch darkness, and

the only light one notices is from thebeacon that outlines a large vessel justoff the shores of Bintulu.

It is almost surreal that idyllic Bintuluis where the world-class, high-tech syn-thetic fuel (SynFuel) is produced – thevery same fuel that powered the AudiR10 TDI race cars into motor-racinghistory. This was the first time that adiesel-powered race car had taken over-all victory at Le Mans.

The fuel that was used in the V12 fittedin the Audi R10 TDI started its journey20 km offshore from the Central Luconiaoil and gas field, off the coast of Bintulu.The natural gas that is piped in is clever-ly transformed into a series of differentproducts, ranging from naphtha, kero-sene, gasoil, solvents, drilling fluids andwaxes. The entire process utilises alabyrinth of concrete, pipes, pumps,vents, and massive finished productstorage tanks.

Nothing unusual you might think. Un-til you see the plant. The Shell Bintuluplant is distinctively clean for a “refin-ery”; even the bio-sludge can be used asa soil improver for local agriculture. Justfrom the look of the plant, I would neverhave guessed what lies beyond, andcould have mistaken it for a giant foodprocessing facility. Visually, the plant isimpressive with many huge coolingfans and steam occasionally ventingfrom the ground.

During this visit, Willem Scholten,Shell’s Senior Technologist, was my

“tour guide”. Thanks to his vivid descrip-tion of how the natural gas is convertedto liquid fuel, I learnt a lot and came tounderstand how the clear and odour-less product that this plant produces isSynFuel – the same that Audi engineersuse to power their R10 race car.

The fuel produced is so “pure” andpowerful that the Audi R10 summonedits most formidable SynFuel-poweredcars to do battle with its fossil fuel rivalson the asphalt at Le Mans. The versionused in the Audi R10 may never make it into the fuel tank of a normal dieselvehicle (then again, a normal dieselvehicle isn’t expected to produce 650horsepower and 1,100 Nm of torqueeither!), but is currently blended andsold as Shell V-Power diesel throughoutEurope and Thailand, and enjoyed byhundreds of thousands of vehicles.

… to top of the podium With the aid of this top-quality diesel,the R10 is virtually untouchable when itcomes to endurance on the track. Theability of the R10 to stay on the Le Manstrack for two more laps per 90-litre tankof diesel fuel compared to its petrol-dependent competitors gave the R10the decisive edge. This translates to anaverage speed of 233 km/h and a carcapable of lapping the Le Mans circuitin 3 minutes and 30 seconds.

And thus it came to pass on 18 June,2006 that the R10, with the help of thehumble methane gas from the off-shore

Below: A view of thenatural gas processingplant in Bintulu.

Above: A friendly smile for a “clean” project. The locals live a calm,nonchalant life.

The new technology contributes to clean airThe Audi TDI programme dates back to the late 1980s as a revolt against

the smelly, rattling diesel which was the only alternative means of

transport based on better fuel economy. The seemingly unattainable

development goal which Audi set itself brought the TDI programme

into existence. Fast forward to the year 2006 – no car manufacturer

has ever attempted to win a sports car race such as Le Mans with

a diesel-engined race car. Having taken three successive victories at

Le Mans, the Audi motor-racing veterans saw in the new set of

regulations stipulated by the organisers the chance to field a diesel-

powered race car. For Audi, a company which firmly believes in taking

on seemingly impossible challenges, this proved to be an excellent

opportunity to change people’s view of motor-racing – and indeed of

diesel-powered cars!

The intricate V12 powerplant at the heart of the R10 is a diesel unit

with racing genes. The ultimate challenge was to develop an engine

which would develop 650 horsepower and 1,100 Nm of torque reliably.

This required special piston geometry and exceptionally reliable

build quality. The racing diesel also had to embody the virtues of the

Audi TDI road cars. The engine had to be quiet with minimal exhaust

emissions and improved fuel economy.

William Whey (Singapore) indulges

his passion for cars as an author

for various automotive titles

and columns. He also works as a

consultant for a leading tyre manufacturer

and for the Automotive Association of

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fields of Bintulu, captured the racetrophy and triumphantly took the topstep on the podium – a truly historicmoment. This signified the end of thegruelling race but marked the begin-ning of a new chapter in the world ofmotor-racing.

This commitment from Audi and Shellushered in an era of performance-oriented vehicles that are not only effi-cient, but extremely fast to drive too –making it possible to drive the futuretoday.

Smell the roses Shell has been working on gas-to-liquid(GTL) technology since the 1970s. Thewide-scale commercialisation of thistechnology will benefit our environmentwithout any negative effect on the waywe live. The liquid produced is clear andodourless. Without proper labelling it isnearly impossible to distinguish it fromwater with the human eye or nose. The diesel produced by this method isclean-burning thanks to its high cetane

number. Compared to other “sulphur-free” diesels, sulphur-free Shell V-Powerdiesel leads to greater reductions in lo-cal pollution and is convenient and easyto use, without the engines having toundergo any significant modifications.Shell V-Power diesel containing GTL fuelis already available in a host of Euro-pean countries. It is available on trial inthe USA, the UK and China in its pureGTL form. Vehicles using this fuel havebenefited from lower fuel consumption,reduced emissions, less engine noiseand better driveability.

Energy of the future

Fine fuels from farmlandWood, plants and compost are all serving as sources of a top-grade diesel fuel. The CHOREN company manufacturesSunDiesel fuel at Freiberg, Saxony. A clever move that is also helping the environment. Text Peter Weißenberg // Photos Jens Neumann

Managing Director ofCHOREN Carlhans Uhleplans to have the new

SunDiesel plant in opera-tion by the end of 2007.

Dietmar Rüger, Head ofProcess Engineering,

is proud of the CHORENfacility that supplies

particularly high-performance biofuel.

Peter Weißenberg, 41, is Head of

the Business and Consumer Sec-

tion and Deputy Editor-in-Chief of

the Sächsische Zeitung newspaper.

Born in Wuppertal, he has also written several

books on business and the stock market.

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D ietmar Rüger would love to tellhis family about his “day at theoffice” when he gets home at the

end of a long day. After all, the 46-year-old is rather proud of what he does. “Butmy daughter isn’t really interested,” saysRüger, shrugging his shoulders. Well,how many twelve-year-old girls reallywant to hear about synthesis gases madefrom carbon monoxide and hydrogen?

Perhaps the Head of Process Engineer-ing at the CHOREN company shouldadopt the following approach: “I’m turn-ing German farmers into the oil sheikhsof the future.” Even a teenager mightfind that almost as exciting as being ableto declare: “My dad’s a horse whisperer!”

In the eyes of engine or fuel developersand the prime movers of environmentalor economic policies everywhere fromChina to California, Rüger’s work ap-pears even more exciting. They are al-most queuing up, safety helmet in hand,to view CHOREN’s football-pitch-sizedconstruction site in the foothills of theOre Mountains. That is where, on theedge of the small town of Freiberg, spe-cialists such as the wiry Saxon are build-ing a chemical plant that could help tosolve the energy problems of the future –and reconcile economics with ecology:Rüger and his colleagues are makingone of the cleanest fuels in the worldout of wood, green waste and compost:SunDiesel.

Even the name of Rüger’s employer,CHOREN, hints at its agenda: C for carbon,H for hydrogen, O for oxygen and REN forrenewable. The latter is the main objec-tive of this pioneering company, in whichthe petrochemicals giant Shell holds astake of around 25 percent. “We want torecreate the natural cycle at our plant,”explains management expert CarlhansUhle, one of the three directors, as he sur-veys the gently rolling hills dotted withforests and fields as far as the eye cansee. These are CHOREN’s green oilfields.

Plants use the sun’s energy to grow,then decompose into energy sourcessuch as coal, natural gas or, as illustratedin this specific instance, oil. A processthat normally takes 400 million years.The Freiberg company has recreated ina patented process what otherwise takeseons – stumps, sticks, flowers and fruits,

branches and trunks are all transformedinto precious diesel fuel in 20 minutes.

Fully biodegradable“Our first economically operating plantwill be completed here by the end of2007,” explains 48-year-old Uhle, sur-rounded by 20-metre-high steel scaffold-ing; they will soon be supporting a com-plex pipework structure that will cooldown the gases from the biomass andtransform them into the precious fuel. At the rate of 16,000 tonnes a year. Atest facility just alongside it has alreadydelivered incontrovertible proof thatCHOREN’s “magic” process for makingdiesel fuel genuinely works.

Particularly importantly for Uhle,“SunDiesel isn’t just any old biofuel.” Itdelivers much more energy – and doesnot do any more damage to the globalclimate than plants such as the gera-niums on Uhle’s balcony. It is not even aparticular problem if residues from theliquid seep into the ground. “That’s be-cause our fuel is entirely biodegradable,”beams the financial expert Uhle. Everyuser of conventional diesel will more-over appreciate the fact that SunDieselis crystal clear and entirely odourless.

In 2009 CHOREN will be building itsfirst plant of an economically optimalscale: it has a designed annual capacityof 200,000 tonnes of SunDiesel. “It willneed a catchment area of around 30 kilo-metres, with forests and farmland,” addsUhle. The pioneering company alreadyowns a suitable site in Mecklenburg-Western Pomerania. But at present,

managers and politicians from all overthe world are clamouring to attract thisreference facility to their own region. Hisexpert, Rüger, is currently in the processof training new chemists and machineoperators, and amid a forest of steeltanks the size of a small car, with fire-red cladding the thickness of a person’sarm, explaining precisely how the top-secret plant is operated. That is one ofthe key reasons why the VolkswagenGroup, another of CHOREN’s backers,would prefer it to be sited in Germany.But the SunDiesel idea can in principlebe applied wherever there is vegetation.It seems almost paradoxical at a timewhen oil and gas are in short supply, butCHOREN’s specialists perceive amplepotential for raw materials. By as earlyas 2025, as much as a quarter of alldiesel fuel used in Germany could beproduced domestically.

Dietmar Rüger is not the only one to beconvinced that a network of SunDieselplants will be supplying fuel to Germancar drivers within as little as a decade. Bythen, even his daughter might realisehow proud she can be of her father –every time she calls in at the fillingstation.

400 million years in 20 minutesHow CHOREN makes diesel from wood, compost and plants

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of carbon dioxide are still

present. This gas is then further

processed.

CHOREN uses the subsequent

Fischer-Tropsch process to

convert the purified synthesis

gas into the biofuel SunDiesel.

3

fier operating at temperatures

of up to 1,600 degrees Celsius.

The organic compounds are

unable to withstand such high

temperatures, which produce a

synthesis gas (carbon monoxide

and hydrogen) in which traces

2

Carbo-V process: the stored

biomass is first converted

into solid carbon and gas

containing tar in a gasifier at

around 500 degrees Celsius.

These products are passed

separately into a second gasi-

1

TFSI: high-performance and economical

A global engine

Convinced of the success of the new 1.8-litre TFSI:Wolfgang Hatz, Head of Powertrain Development for the Volkswagen Group.

The Head of Powertrain Development for the Volkswagen Group, Wolfgang Hatz, regards thecombination of a turbocharged petrol engine and direct injection as the “concept of the future”. The new 1.8-litre TFSI engine, appearing first in the Audi A3 and the new Audi A5, serves to confirm this prediction. Text Johannes Köbler // Photos Angelika Emmerling

PROGRESSIVE PERFORMANCE: ENGINE DEVELOPMENT


T he complex in which Audi’sengine developers are based atIngolstadt is a veritable micro-

cosm. A maze of stairways, offices andworkshops, many of them spacious andbright, others tucked away in obscurity,epitomise AUDI AG’s rapid-fire growthover the past few decades. The man atthe helm of this nerve centre of thecompany’s operations is Wolfgang Hatz,born 1959, Head of Powertrain Develop-ment at AUDI AG and since February 1,2007 for the Volkswagen Group.

One particular storey, in a grey-flooredopen-plan office, is home to the CAD de-velopers. This is where the ultramodernengines first begin to take shape. Whatexactly were the main objectives of “De-velopment Order No. 888”, issued fouryears ago? Hatz enumerates them: “Aswell as plenty of power and torque, am-ple refinement, low fuel consumptionand the potential to meet the moststringent emission limits, the core task

The Audi 1.8l 4V TFSI engineDevelopment codename: 888; displacement:

1,798 cm3; stroke: 84.1 mm; cylinders: 4;

cylinder spacing: 88 mm; crankshaft

bearings: 5; power output: 118 kW (160 bhp);

torque: 250 Nm; average fuel consumption

(on the Audi A3): 7.3 l/100 km; fuel type

RON: 95/91; emission standard: EU IV; engine

casing: grey cast iron; engine casing weight:

33 kg.

Despite the additional balancer shaft assembly

and high-pressure injection system, this

engine is 1 kg lighter than its predecessor.

The engine has to withstand intensivetests on the engine test bench.

of this new generation was to optimisecosts quite substantially.” This was themission of the turbocharged 1.8-litreengine with direct injection – a principlewith which the 2.0 TFSI is already enjoy-ing eminent market success.

Wolfgang Hatz is staking out the ter-rain with the 1.8 TFSI, which is about to make its debut in the Audi A3* andthe new Audi A5*: “Audi is already thebiggest manufacturer of turbochargedpetrol engines with direct injection. I’vebeen convinced for years that this is theconcept of the future, akin to the TDI inthe domain of diesel engines.”

The engine workshop on the groundfloor is a hall with workbenches andmeasuring equipment. Hatz greets themechanics with a handshake and headsfor a specimen of the new TFSI. “Seehere,” his Baden accent blending in-congruously with his Bavarian turn ofphrase, “This is the new, virtually no-maintenance toothed chain for thecamshafts. And here are the balancingshafts. We have relocated them insidethe crankcase. That cuts costs and pro-duces more effective mass balancing.We used grey cast iron for the enginecasing for acoustic reasons, but it stillweighs only 33 kilograms.”

Next port of call: the engine test rigs –soundproofed chambers containing aforest of wiring harnesses and exhaustpipes as thick as your arm. The techni-cian at the control desk moves up thecontrol, causing the displays on themonitor to rush by up to a speed of6,500 rpm. A glance through the safety-glass window reveals the manifoldglowing red-hot at a temperature of 950degrees Celsius. “It develops 118 kW –that’s 160 bhp – and 250 Nm torque,from an engine speed of just 1,500rpm,” comments Hatz. “Our new 888 is adownsizing concept. It delivers the per-formance that we were getting from asix-cylinder engine a couple of yearsback, but its fuel consumption is muchlower.”

Newly developed injection systemThe low fuel consumption – averaging7.3 litres per 100 kilometres in the A3 –is also due in part to the combination ofturbocharging with FSI direct injection.

A watercooled turbocharger forces theair into the combustion chambers, anda newly developed injection system in-jects the fuel at 150 bar. These two tech-nologies are an ideal match, becausethe directly injected petrol cools downthe combustion chambers and allows ahigh compression ratio. Audi has al-ready demonstrated the huge potentialof the TFSI principle with its R8 racingcar on circuits all over the world.

“Yes,” says Hatz, his eyes lighting up,“we have been helping to plan all thesetechnologies right from the outset.” Thebasic concept of the successful prede-cessor generation goes back to 1972. Itwas constantly refined in an effort tokeep abreast of changing requirementsover this period of 35 years. “But weeventually reached a point where it wasbetter to make a clean break with thepast, all things taken into consideration.And that’s precisely what we did withour “Global Engine”. An opportunity likethat doesn’t come along very often, withthe entire business costing several hun-dred million euros.”

The 1.8 TFSI represents a major stra-tegic advance for Audi on the world’smarkets. It will be built in six differentversions, cover an extensive perform-ance range and be available in numer-ous different countries. As well as at

“Modern technology is immensely

enjoyable”, believes Johannes

Köbler (44). The freelance motoring

journalist, who is as much at home

in the print sector as in the world of TV and the

online sector, has been monitoring develop-

ments in the car industry for the past 15 years.

* fuel consumption figures at the end of the Annual Report

Gyor, in Hungary, it will be produced atthe brand-new Volkswagen engineplant in Dalian, China. “We will ramp upproduction to around one million unitsa year relatively quickly,” declares Hatz.“And the engine’s codename 888 is re-garded as a lucky number in China.”

“Really fun to drive”A white S3* is standing outside thebuilding – its TFSI, a two-litre version,developing 195 kW (265 bhp). “This carreally is fun to drive,” exclaims Hatz,climbing into the driver’s seat. “0 to 100in 5.7 seconds! Such compelling per-formance really turns the heat up onquite a few six-cylinder engines. I like itssporty sound, though I think we couldincrease it just a touch – we’ll see.”

We roll back into the yard. Hatz climbsout and enjoys a cigarillo before hurryingoff to his next appointment. All part ofthe business of developing even betterengines for an even stronger future.

Audi has secured a leading place in the automotiveworld through the use of aluminium. But there is stillample scope for new developments in lightweightconstruction. The body of the new Audi TT represents a further step in this direction and demonstrates the potential shape of “intelligent lightweightconstruction”. Text Michael Kirchberger // Photos Jens Neumann

Hybrid construction

Lightweight con-struction as standard

Dr. Klaus Koglin (left) and Frank Dreves with thebodyshell of the new Audi TT Coupé. A veritable

featherweight at just 206 kilograms – around 100 kilograms less than the predecessor model.

PROGRESSIVE PERFORMANCE: BODY MANUFACTURING

Joins made from waxJoining together body components on the TT

by means of rivets, bolts, bonding and weld-

ing is a science in its own right. Because steel

and aluminium have different coefficients of

expansion as they become warmer. And solid

lubricant is needed in aluminium forming, an

ultra-thin wax coating applied at the rate of

only one gram per square metre of material.

This wax coating allows “frictionless” forming

of the aluminium. The chemical properties

of the adhesive applied to the surface mean

that it incorporates the wax coating into its

structure, thus producing a secure bond.

Michael Kirchberger, born 1957,

is a freelance car journalist who

writes regularly on technology and

automotive developments for such

publications as the Frankfurter Allgemeine

Zeitung, AUTO ZEITUNG, other trade journals

and daily newspapers.


W hen the first generation ofthe Audi A8 made its debutin 1994, its lightweight de-

sign concept based on an aluminiumframe structure that was referred to asthe Audi Space Frame (ASF) and cladwith aluminium panels caused a realstir. At the “EuroCarBody” congress, theknowledge exchange forum for bodydevelopers, planners and manufactur-ers, this ground-breaking technologyscooped first prize. There then followedthe Audi A2, which proved that alumin-ium can also lend itself to use in volumeproduction. The brand with the fourrings repeated this success with thecurrent Audi A8, once more capturingthe EuroCarBody Award. Aluminiumpanels have now been integrated for thefirst time into a steel body on the cur-rent Audi A6. Finally, in 2006 the newAudi TT made its debut initially as theCoupé, then as the Roadster. It shouldcome as no surprise to learn that Audireceived the 2006 award for the pioneer-ing construction of the TT’s body.

“A hybrid construction approachproved to be ideal for this vehicle con-cept,” explains Dr. Klaus Koglin, Head ofTechnology Development at Audi. Thecombination of the materials alumin-ium and steel has meant that the TTweighs more precisely at the pointswhere this is necessary. Above all theuse of steel at the car’s rear has pro-duced an improved axle load distribu-tion – with the welcome effect that thesporty 2+2-seater exhibits a finely bal-anced weight distribution between thefront and rear axles, unquestionablyenhancing its agility. “The bodyshell ofthe new TT Coupé weighs 206 kilo-grams; that’s about 100 kilograms lessthan its predecessor, despite the body’slarger dimensions,” calculates Koglinout loud.

This result provides an ideal basis forthe developers. A low centre of gravityand an improved axle load distribution,in conjunction with high rigidity, makefor sporty handling. The body’s rigidityis 49 percent higher than that of thefirst-generation TT. Even the Roadster’storsional rigidity has improved substan-tially, despite there being no reinforcingeffect of a sheet metal roof. Its rigidity

has actually increased by over 100 per-cent compared with the previous ver-sion. It is furthermore possible to buildboth model versions on the same pro-duction line. This introduces a high de-gree of variability into the productionprocess, thus cutting costs.

Special production techniqueThe production of the TT is in any caseboth a fascinatingly complex and sur-prisingly illuminating example of howdeeply intertwined production technol-ogy and know-how have become overthe years since Audi embarked on alu-minium construction. Frank Dreves,AUDI AG Board Member for Productionsince February 1, 2007, describes theprocess as modular production islandsthat come together on the line, ratherthan as a conventional form of conveyor-line assembly. “Only this method enablesa smooth combination of modern alu-minium with traditional body-gradesteel,” explains Dreves.

These two materials are fundamen-tally incompatible. Iron and aluminiumare elements with different values in the

electrochemical series. As soon as anelectrolyte such as rainwater comes in-to contact with both of them, corrosionoccurs. ”The aluminium corrodes in theprocess,” continues Koglin. They con-sequently need to be isolated. Audiachieves this by using adhesives that onthe one hand act as insulators and onthe other hand increase the rigidity ofthe join. Fine-seam trims made fromPVC reliably seal off cut edges.

The TT’s production techniques havelargely been adopted from the A2. Theproduction facilities were moved fromNeckarsulm to Ingolstadt for this pur-pose, securing what Dreves terms “asignificant reduction in the costs of TTproduction”. But the finer points of alu-minium expertise go much further thanthis. In arc welding, for instance, it isimportant to perform welding in the so-called flat position if a high-quality weldseam is to be achieved. That is why Audiuses robots operating as an ensemblein the 98 percent automated productionprocess. While one of the two robots isperforming the welding work, the otherbrings the weld point into the ideal flatposition.

A glance at the finished body bearstestimony to the quality standardswhich Dreves sets. The lines along thesheet metal surface of the TT, an unerr-ing measure of an outstanding body fit,resemble the work of a car-obsessedartist-cum-aesthete.

According to Koglin and Dreves, Audiwill be steadily developing applicationsof aluminium over the next few yearsbecause this material will continue toplay an instrumental role in determin-ing innovative body concepts.

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