High Quality Content by WIKIPEDIA articles! The Volkswagen 1-litre car is a two-person diesel concept car produced by Volkswagen. The 1-litre car was designed to be able to travel 100 km on 1 litre of diesel fuel, (equivalent to 235 miles per U.S. gallon or 282 mpg Imperial), while being both roadworthy and practical. To achieve such economy, it is produced with lightweight materials, a streamlined body and an engine and transmission designed and tuned for economy. This concept car has been modified, first in 2009 as the L1 and in 2011 as the XL1 (see below).