And the auto lobby whines about how much it will cost them...Bullshit, the rest of the world is doing it.
Info from Wiki here:
http://en.wikipedia.org/wiki/Mileagesnip
The average fuel efficiency of European cars is over 40 mpg (5.9 L/100 km), Japanese cars 45 mpg (5.2 L/100 km), and North American cars 20.4 mpg (11.5 L/100 km).<1>
An interesting example of fuel economy is the popular microcar Smart ForTwo, which can achieve up to 3.4 L/100 km (69.2 mpg) using a turbocharged three-cylinder Diesel-engine. The Smart is produced by DaimlerChrysler and is currently only sold by one company in the United States (see external link ZAP). The current record in fuel economy of production cars is held by Volkswagen, with a special production model of the Volkswagen Lupo (the Lupo 3L) and the Audi A2 that can consume as little as 3 litres per 100 kilometres (78 miles per US gallon or 94 miles per Imperial gallon). The production lines for the Audi A2 und Volkwagen Lupo closed in June 2005.
Diesel engines often achieve greater fuel efficiency than petrol (gasoline) engines. Diesel engines have maximum energy efficiency of 45% and Petrol engines of 30% <2>. That's one of the reasons why Diesels have better fuel economy that equivalent petrol cars. A common margin is 40% more miles per gallon for an efficient turbodiesel. For example, the current model Skoda Octavia, using Volkswagen engines, has a combined Euro mpg of 38.2 mpg for the 102 bhp petrol engine and 53.3 mpg for the 105 bhp — and heavier — diesel engine. The higher compression ratio is helpful in raising efficiency, but diesel fuel also contains approximately 11% more energy per unit volume than gasoline.<3> Diesels consume less fuel also when operating at low power output or at idle, because they can run with leaner mixtures than can spark ignition engines. On the other hand the weight difference is significant for powerful cars.
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