想象一下，一辆火车消无声息地沿着铁轨运行，排放物中的有毒物质不过是水。

　　That train is a reality.

　　这种火车是真实存在的。

　　In March, Germany conducted successful tests of the world's first "Hydrail" - a hydrogen powered, zero-emission train.

　　3月份，德国成功测试了世界上第一辆“氢铁”，这是一种零排放的氢气动力火车。

　　"The new train is 60% less noisy than a traditional diesel train, completely emission free," said Jens Sprotte of Alstom, the French producer of the train. "Its speed and the possibility to transport passengers match the performance of a diesel train."

　　来自氢铁制造商法国阿尔斯通公司的詹斯?施普罗特称：“与传统柴油火车相比，氢铁的噪音降低了60%，完全是零排放。其运行速度和载客能力与柴油火车不相上下。”

　　"The only sound it gives off comes from the wheels and air resistance," Sprotte added.

　　施普罗特表示：“氢铁唯一发出的声音来自车轮和空气阻力。”

　　Here's how the new technology works:

　　下面是这项新技术的原理：

　　The Hydrail uses the same equipment as a diesel train but substitutes hydrogen as its fuel source. Large fuel cells sitting on top of the train combine hydrogen and oxygen to generate electricity, which is then transferred to lithium ion batteries.

　　氢铁使用的设备与柴油火车相同，但以氢气取代柴油作为其燃料来源。火车顶部安装的大型燃料电池将氢气与氧气结合产生电能，随后电能被转移到锂离子电池中。

　　Energy that is not immediately used can be stored for later use, increasing fuel efficiency. The train's only emissions are steam and water, resulting in minimal impact to the environment.

　　没有立即使用的能量将被储存起来，以备后续使用，这提高了能源效率。氢铁的唯一排放物是水蒸汽和水，对环境造成的影响极小。

　　"It's so clean you can breathe it in," said Stefan Schrank, the train's project manager at Alstom.

　　阿尔斯通公司氢铁项目经理斯蒂芬?施兰克表示：“氢铁排放的废气干净到可以呼吸。”

　　Five federal states in Germany have signed a letter of intent to purchase a total of 60 trains from the French firm.

　　德国有5个联邦州已经签署了购买意向书，从阿尔斯通共计购买60列氢铁。

　　Each two-car train set requires a fuel cell and a 207 pound tank of hydrogen to supply it. The oxygen is supplied from the air around the train.

　　每个两节车厢的列车组需要一个燃料电池以及一个207磅（约为94公斤）的氢气罐提供动力。氧气可从火车周围的空气中获得。

　　The train can travel up to 500 miles per day on a single tank of hydrogen, carrying 300 passengers at a time.

　　氢铁消耗一罐氢气平均每天最多可行驶500英里（约为800公里），一次可搭载300名乘客。

　　The first operational trains will roll out by the beginning of 2018, providing a green alternative to the 4,000 diesel trains currently operating in Germany. According to the EU, about 20% of Europe's current rail traffic runs on diesel.

　　第一批运营列车将于2018年初面世，为德国现在运行的4000辆柴油火车提供环保的替代选择。据欧盟统计，目前欧洲20%的铁路线路上运行的是柴油车。

　　The new train is ideally suited for short stretches of the European network that have not been converted to electric rails.

　　这种新型火车非常适合欧洲铁路网中没有转换成电力轨道的短程线路。

　　Alstom are hoping the train will turn a profit within its first couple years of operation. They hope the model will replace Germany's fleet of diesel trains in five to 20 years.

　　阿尔斯通期望在氢铁开始运营的最初几年内就能盈利，也希望氢铁能在5-20年内取代德国的柴油列车。

　　The Netherlands, Denmark, Norway and the UK have also expressed interest in the train.

　　荷兰、丹麦、挪威和英国也对氢铁表现出兴趣。