When I bought a train ticket recently from Hamburg, Germany, to Copenhagen, Denmark, little did I know that I was in for a ride on an award-winning hybrid ferry. The high-speed direct train made a stop in Puttgarfen and the conductor asked everyone to prepare to exit the train after it was loaded onto the Scandilines ferry.

Sure enough, the train rolled right onto Deck One of the 465' Prinsesse Benedickte, along with some 300 other cars and trucks. We disembarked the train and watched as the ferry began its 18 km crossing to the Danish port of Rodsby.

The ferry was converted in 2013 by Copenhagen-based Scandlines from diesel electric to hybrid using advanced lithium polymer battery modules from Canada-based Corvus Energy. This is the largest marine battery pack ever attempted. The Prinsesse Benedickte can propel the massive 14,800 lbs. vessel for 30 minutes without using diesel and recharge in 30 minutes from onboard generators.

Scandilines is investing heavily in sustainable technologies, including $31 million on refitting the other vessels on the Puttgarden-Rodsby run. The success of the conversions has garnered lots of attention and awards for the company and Corvus, including the Fathom Ship Efficiency Award in October. Fini A. Hansen, technical superintendent, fleet management, Scandlines Denmark ApS, said that his company's investment in hybridizing its fleet will benefit both the environment and the ferry operator in terms of increased efficiency.

The ferries are said to reduce CO2 emissions by 15%.

Of course, my fellow passengers seemed oblivious to the fact that they were riding on the world's largest hybrid vessel. They were far more focused on getting to the tax-free alcohol shop on the passenger deck and stocking up before entering Danish waters where a beer can easily set you back $15. Salute!

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