Germany on Monday rolled out the world’s first hydrogen-powered train, signalling the start of a push to challenge the might of polluting diesel trains with costlier but more eco-friendly technology.

S Germany
V [rolled out]
O (the world’s first) hydrogen-powered train 水素で動く電車
,
補足
V [signalling]
the start どんな→ [of] a push プッシュのスタート
どんな→
[to challenge] チャレンジすること
O the might どんな→ [of] (polluting) diesel trains 汚染するディーゼル電車
[with] costlier

[but]
more eco-friendly technology 環境に良いテクノロジー