Monday, November 19, 2007

Hybrid Audi.


Audi {link}, along with every other major German manufacturer (including Porsche), are working industriously on hybrid technology for their model range. Their current philosophy is to use Lithium Ion batteries in conjunction with some form of internal combustion engine. Only when the batteries are capable of being mass-produced will there be a wide range of hybrid Audis available. Whilst this sounds like a long wait the new incarnation of the Audi A4 is expected to be available as a hybrid in the not too distant future.
The Audi Metroproject Quattro concept, which had its debut at the recent Tokyo Motorshow, gave clear indications as to how close to production the new Audi hybrid system is. It also gave an interesting glimpse into possible transmission configurations; the Metroproject is four wheel drive but the front wheels are drive by an internal combustion engine whilst the rear are powered by an electric motor. Ironically this allows the Audi Metroproject to be front wheel drive, rear wheel drive or four-wheel drive!
The Audi Q7 will be available as of next year with hybrid technology, using a 36-kilowatt electric motor positioned between the normal V6 and the automatic gearbox. This will allow better performance whilst reducing fuel consumption and emissions. The Q7 isn’t available with the new lithium ion batteries, it will nickel hybrid batteries.
Audi have also developed a hybrid A5 although this uses natural gas in conjunction with petrol to power its 163PS turbo engine. The A5 T-CNG as it is known is aimed squarely at reducing CO2 emissions hence the use of natural gas. Natural gas (from the earth’s reserves) emits approx 20% CO2 compared to petrol so is the obvious choice for a quick and easy way to reduce a car’s CO2 emissions. By using commercially grown and produced natural gas the figure can be reduced even more as this gas only produces the amount of CO2 the plants absorbed during their growing period.
Combining a mixture of ethanol and petrol (an 85/15 split is ideal) Audi have also been able to produce a vehicle with substantially lower CO2 emissions than a standard petrol powered car. Ethanol requires extensive modifications to the fuel tank and pipes but, unlike natural gas, requires no extra fuel tanks. This ensures that an Ethanol powered Quattro remains a possibility; a natural gas powered Quattro is currently impossible because the extra fuel tanks are positioned over and around the rear axle. Another advantage of ethanol is its lower price compared to petrol and natural gas, although this is somewhat negated by the fact that current ethanol technologies have been unable to produce fuel consumption as low as petrol power.