Germany is currently testing the world’s first carbon dioxide emission-free train powered by hydrogen. The passenger trains—whose only emissions are steam and condensed water—were revealed last month at the Berlin InnoTrans trade show.

The Coradia iLint, created by French company Alstom, generate energy by combining hydrogen stored in tanks on the train with oxygen in the air. The energy is stored in lithium-ion batteries on board.

There are other benefits, too: The trains have lower noise levels than diesel-powered trains, as the only sound they make are from the wheels on the track and air resistance as they rush along at 140 kilometers per hour.

The train can travel up to 700 kilometers on a single hydrogen load and carry up to 300 passengers, making it the first of its kind to regularly operate long distances.

Alstom is testing the trains throughout the year with plans to begin carrying passengers in Germany in late 2017 or early 2018.

Alstom says the cost of its new trains will be similar to that of the diesel-powered ones, making it an attractive option for railway companies.