On Dec. 13, 2001, DaimlerChrysler demonstrated fuel cell vehicles powered by four different fuels. The vehicles were gathered together for the first time at DaimlerChrysler’s facility at the California Fuel Cell Partnership, a collaboration of automotive and energy companies and government agencies that is demonstrating and testing fuel cell-vehicle technologies.Fuel cells combine oxygen from the air and hydrogen from a fuel source to produce electricity, which can be used to power electric motors and drive automobiles. DaimlerChrysler and other automakers are exploring a variety of fuels that can produce hydrogen onboard vehicles.The vehicles shown were:-- Chrysler Town & Country Natrium, which is fueled with sodium boro-hydride, a compound related to borax. The Natrium was introduced Dec. 12 at the Electric Transportation Industry Conference in Sacramento.-- NECAR 4, which operates on liquid hydrogen.-- NECAR 4a, fueled by compressed gaseous hydrogen.-- NECAR 5, which operates on methanol. NECAR 5 is being shown for the first time in North America.The three NECAR vehicles are based on the Mercedes A-class passenger car.In 1999, DaimlerChrysler also unveiled a luxury sport/utility concept vehicle called Jeep Com-mander, demonstrating gasoline-fueled fuel cell-engine technology.DaimlerChrysler will market the first fuel cell city buses in 2002 and fuel cell-powered passenger cars in 2004. To meet those goals, DaimlerChrysler is investing more than $1.4 billion in fuel cell technology research and development during the period 2001-2004.