He estimates the hydraulic hybrid bus would offer a 20 percent cost savings over a conventional diesel during a 12-year lifespan and a 30 percent cost savings over a diesel-electric hybrid.

他估计，在一辆公交车12年的寿命期间，液压混合动力公交车将比常规的柴油车节省20%的成本以及比一辆柴油-电力混合动力车节省30%的成本。

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One specific barrier to wider adoption of the electric bus must be the external demand of operators for "unlimited" mileage - that is, for vehicles (i. e. diesel engines) with total flexibility.

一个具体障碍，更广泛地采用电动客车的经营者必须为“无限”里程外部需求-这是总的灵活性车辆(即柴油发动机)。

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