The keys to the incredible mileage in the Volkswagen XL1 were reducing the weight of the vehicle and eliminating wind resistance. The XL1 only weighs 1,753 pounds — that's more than a thousand pounds lighter than the Toyota Prius, which weighs in at 2,921 pounds. The wheels on the Volkswagen XL1 are as thin as road bike’s and wrapped in custom Michelin rubber. The XL1 chassis is a single piece of molded carbon-fiber, and has a drag coefficient of only 0.189 – similar to a bumblebee."
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