Efficiency and driving fun
High-tech, lightweight construction, perfect aerodynamics and the plug-in hybrid system consisting of a two-cylinder TDI engine (48 hp), E-motor (27 hp), 7-speed dual clutch gearbox (DSG) and lithium-ion battery (capacity: 5.5 kWh) enable the new Volkswagen XL1 to emit a mere 21 g/km CO2. If needed, the XL1, which reaches (electronically limited) 160 km/h, accelerates from 0 to 100 km/h in just 12.7 seconds.
Third evolutionary stage of a vision
Conceptually, the XL1 represents the third evolutionary stage of Volkswagen's 1 liter car strategy. When the new millennium was ushered in, Prof. Dr. Ferdinand Piëch, who is today chairman of the Supervisory Board of Volkswagen AG, formulated the visionary goal of bringing to market a production car that was practical in everyday use with fuel consumption of one liter per 100 km. In the two-seat XL1, this vision has become reality. Despite the very high levels of efficiency of the XL, developers were able to design a body layout that offers greater everyday practicality than in the two previous prototypes: while the driver and passenger sat in a tandem arrangement for optimal aero-dynamics in the L1 (the 1 liter car presented in 2002 and in 2009), in the new XL1, two occupants sit side by side, slightly staggered but almost like normal.
Shorter than a Polo, lower than a Porsche Boxster
The XL1 is 3,888 mm long, 1,665 mm wide and just 1,153 mm tall. These are pretty extreme measurements if you go by familiar passenger car standards. By way of comparison, the Polo has a similar length (3,970 mm) and width (1,682 m) but is significantly taller (1,462 mm). Even a full-blooded sports car like the latest Porsche Boxster is still 129 mm taller (1,282 mm). The presence of the XL1 is correspondingly spectacular - a car of the future, built in the present day.
CFRP and aluminum dominate
Not only are the XL1's technologies pioneering but also Volkswagen is producing large parts of the XL1 in lightweight and strong carbon fiber reinforced polymer (CFRP). The monocoque with its slightly offset seats for driver and front passenger, all exterior body parts as well as functional elements such as the anti-roll bars are all made of CFRP. The preferred CFRP components at Volkswagen are those produced in the RTM process (Resin Transfer Molding). The density of this material or its specific gravity is merely around 20 percent that of a comparable steel exterior skin. The CFRP parts exhibit a level of stiffness and strength that is by no means inferior to that of comparable steel or aluminum parts, yet the exterior skin of the XL1 is merely 1.2 mm thick.
The Volkswagen weighs just 795 kg. Of this figure, 227 kg represents the entire drive unit, 153 kg the running gear, 80 kg the equipment (including the two bucket seats) and 105 kg the electrical system. That leaves 230 kg, which is precisely the weight of the body - produced largely of CFRP - including wing doors, front windscreen with laminated glass technology and the ultra-safe monocoque. A total of 21.3 percent of the new XL1, or 169 kg, consists of CFRP. In addition, Volkswagen uses lightweight metals for 22.5 percent of all parts (179 kg). Only 23.2 percent (184 kg) of the new XL1 is constructed from steel and iron. The rest of its weight is distributed among various other polymers (e.g. polycarbonate side windows), metals, natural fibers, process materials and electronics.
Thanks to CFRP, the XL1 is not only light in weight but very safe as well. This is due in part to the high-strength and yet lightweight CFRP monocoque. In an emergency, it provides driver and passenger with the necessary survival space. The intelligent design of the load paths, including the use of sandwich structures in the monocoque, is responsible for this. In addition, the aluminum structures of the front and rear sections absorb the majority of the impact energy. These principles were likewise implemented in the design of the CFRP doors, where an aluminum absorbing beam is responsible for the absorption of the energy; moreover, a stiff CFRP door frame minimizes the intrusions into the CFRP safety cell. The rescue of the passengers was also given a great deal of attention. In case the XL1 overturns and comes to a rest on the roof, pyrotechnical separating screws facilitate the opening of the doors (swing doors).
XL1 embodies what is feasible today. The new XL1 is currently the most fuel efficient and eco-friendly automobile in the world. The only reason that this vehicle could be built is because the limits of what is feasible both in terms of the technologies utilized and the manufacturing method were redefined. Consider XL1 technologies: Volkswagen is implementing the most innovative systems and materials that offer the highest efficiency possible today. Consider XL1 manufacturing: in Northern Germany, Europe's largest carmaker has set up a completely new handcrafting-like production for the XL1, which consists largely of CFRP.
Manufacturing in Osnabruck
The XL1 is manufactured by Volkswagen Osnabruck GmbH. In the former Karmann plants there, around 1,800 employees produce such cars as the Golf Cabriolet and the new Porsche Boxster. However, in the small production series for the XL1, the specialists from Osnabruck are not pursuing the classic path of large-scale production; instead, they are practicing automotive handcrafting. As is usual in the framework of mass-produced vehicles like the Golf Cabriolet, many components such as the monocoque, engine, motor, suspensions and battery are supplied by other plants and external suppliers. Nonetheless, the XL1 production processes implemented in Osnabruck are highly innovative and unique worldwide. There are no previous examples of the individual production steps anywhere in the world, because no other car has been produced so thoroughly in a similar composite material. On a long-term basis, other Group brands will also benefit from the numerous innovations implemented in the XL1.