In addition, the technology for low-polluting, energy-efficient means of transportation, such as new diesel-fueled vehicles, and the technology for using alternative power sources such as fuel cells and biofuels in motor vehicles has seen considerable progress over the past few years. However, the associated costs remain high.
此外，低污染、低耗能的運輸工具如新柴油車，以燃料電池、生質燃料等替代能源運用在車輛的技術，近年已有長足進步，但是成本仍然很高。