With Volkswagen having just debuted the Jetta TDI in the U.S. market, the question is what comes next? Volkswagen and Audi have already announced plans to launch diesel versions of the Touareg and Q7 early in 2009 with a 3.0L V6. The compact Audi A3 shares a platform with the Volkswagen Rabbit/Golf and Jetta and in Europe it's available with the same 2.0L diesel that's in the Jetta. Fourtitude reports that Audi North America is considering adding the TDI powerplant to the A3. The European A3 offers the 170 hp version of the 2.0L but if it does get offered here it would likely be only with the same 140 hp unit offered in the Jetta. This way Audi would not have to certify another engine. Audi officials, of course, will not comment on such speculation, but if it does happen it likely wouldn't be before 2010. Most likely, Audi will be watching how the already-announced diesels fare in the U.S. market before making a final decision.

[Source: Fourtitude]

While Audi's exhaustive press release accompanying the launch of the newly-revised-for-2009 A3 mentioned both the availability of new diesel engines along with a seven-speed version of the dual-clutch S tronic transmission, Audi's arm in the UK has decided it's worth mentioning them again. This time, though, statistics regarding the reduction of carbon emissions are given, so decided we'd share them too. For instance, the revised '09 2.0 TDI with 140 horsepower, which was rated at 52.3mpg (US) last year, jumps to 55.4mpg, while reducing CO₂ output from 143g/km to 134g/km. Audi also points out that the new 105 horse 1.9 TDI e offers a low CO₂ output of 119g/km while gaining standard manual air conditioning. The e series from Audi, like the Bluemotion models from VW, are designed specifically with low carbon emissions in mind. Too bad the 1.9 TDI e engine comes paired with a five-speed manual only, as the mileage would likely increase with the addition of the seven-speed S tronic. See all of the available powertrain combinations in the press release after the break.

We'll relay the information in this article on Auto 123 in the ever-popular backwards-first method of news reporting. That article ends this way: "Further down the road, as oil reserves become exhausted, bigger and better solutions will be needed." While that may seem obvious, another point worth pondering is this: why wait until then?

In an effort to stave off the impending exhaustion of our oil reserves, Audi is testing and marketing a few alternatives to the gasoline engine. While still relying on some fossil fuels for power, the E85-capable A5 coupe (the red one above) uses far less crude oil than the standard 2.0 four-cylinder would. Of course, ethanol raises other environmental issues which we'll save for other posts. Audi also has A5 models powered by CNG. Then there are the obligatory hybrid models that will be made available by Audi shortly in the form of the Q7 and its 3.6-liter V6 coupled to an electric motor. Of course, Audi is rightly proud of their class and Le Mans leading diesel technology. Although dealyed, these vehicles are likely to be sold in the U.S. in addition to Europe.

Lastly, in the "one of these things is not like the other" category, Audi is showing off some alternatives to the... uh, alternatives mentioned above: monitoring driving habits. The writers at Auto 123 were not so sure that this technology would be accepted in the marketplace, and they may be right. But, we are sure that there are a certain number of drivers who would welcome a little training on how to eke the most miles from a gallon of fuel as possible. Bring it on, Audi!

[Source: Auto 123]

I suppose you could argue that any car that will be exempt from the recently proposed London congestion charge has, for people who drive regularly in the city, a big minus sign under the price tag. The number following that minus sign differs depending on the way the car will be used, but that there is an effective discount for these cars is not escaping automakers. The latest example comes from Audi, which is making it clear that the new A3 will be exempt from the updated congestion charges should they go into effect. The exempt, green version of the A3 emits 119g/km of CO2 from a 1.9 TDI and gets 62.7mpg (combined). Not bad for a large hatchback, don't you think?

This A3 was designed specifically to break through the 120 g/km of CO2 limit in the proposed changes and is more economical than the 1.4L TFSI A3 that was introduced earlier this year (proof that greener legislation works). Audi engineers used reduced rolling resistance tires and a modified 105PS diesel with friction-minimizing components and a manual gearbox that offers the driver a dashboard indicator about when to make the most economical gear shifts. Audi says these changes will drift into future models.

Starting in October, Audi will offer three- and five-door versions of the A3, starting at £16,660 OTR. Read more after the jump. If you're in London, check with the dealer to gauge what your personal minus sign might be.

Related:

• Audi adds the 1.4L TFSI engine to the A3 lineup
• Audi offers economical new A3 and A4 models

[Source: Audi]