Volkswagen XL 1 Spotted Testing Share Comments Our spy photographers have spotted Volkswagen out testing their super-lightweight plug-in hybrid XL 1 which is headed for limited production in the next year. Powered by a hybrid two-cylinder TDI and an electric motor, the XL 1 is designed to be an ultra high efficiency low-emissions vehicle. The carbon fiber monocoque chassis weighs less than 525 lbs. and the streamlined shaped is designed to minimize drag as much as possible. Prototypes reportedly average more than 250 mpg combined cycle. We don’t expect the XL 1 to go on sale here in the State, but stranger things have happened. Click the photos below for larger views.