In just about a month, Green Car Journal, at the 2014 Washington Auto Show, will present the winner of the 2014 Green Car Technology of the Year Award to one of ten nominees.
What makes a green car green but the technology that powers it? The first nominee we considered, the Acura RLX SH-AWD’s powertrain offers the performance of a standard V6 engine, but the fuel economy of an i4. The technology is only slightly more expensive, yet accessible to the public, albeit only to the >$60,000 crowd. Today, we consider the Audi 3.0ℓ TDI Diesel Engine, which can be found in the Audi A6, Q5, and A8 L, among others.
The new 3.0ℓ diesel engine, of turbocharged direct-injection (TDI) design, is already more fuel-efficient than gasoline engines, but incorporates a couple of technologies that make it more fuel-efficient than comparable diesel engines. Audi estimates that the 3.0ℓ TDI will be over 30% more fuel-efficient than it’s own 3.0ℓ TFSI (Turbocharged Fuel Sequential Injection?), which translates to roughly 30% fewer carbon dioxide (CO2)emissions. The high compression-ratio results in a more complete burn, generating fewer unburned hydrocarbons (HC). The variable vane turbocharger also makes for good performance across most of the engine’s operating range.
What makes an Audi, powered by the new TDI Diesel Engine, a green car? First, consider that diesel fuel is almost universally available, and diesel-powered vehicles are already inherently more fuel-efficient. An improved catalytic converter reduces CO2 emissions, by an additional 12%, and nitrogen oxide (NOx) emissions by 95%. Second, the new Audi 3.0ℓ TDI engine is also available with a start-stop system, further reducing fuel consumption. Finally, the engine delivers the performance that will actually make people want to drive it. The only drawback is the price of these vehicles which, being of the luxury class, start at $46,500.
Image © Audi of America