COMPRESSED NATURAL-GAS AND LIQUEFIED PETROLEUM GAS AS ALTERNATIVE FUELS

The use of alternative fuels in the transportation industry has gained a strong support in recent years. In this paper an attempt was made t o evaluate the use of liquefied petroleum gas (LPG) and compressed nat ural gas (NG) by 25 LPG-bifuel and 14 NG-bifuel vehicles that are oper ated by 33 transit systems throughout Nebraska. A set of performance m easures such as average fuel efficiency in kilometers per liter, avera ge fuel cost per kilometer, average oil consumption, and average opera tion and maintenance cost for alternatively fueled vehicles were calcu lated and compared with similar performance measures of gasoline power ed vehicles. The results of the study showed that the average fuel eff iciency of gasoline is greater than those of LPG and NG, and the avera ge fuel costs (dollars per kilometer) for LPG and NG are smaller than those for gasoline for most of the vehicles under this study.