Up to 30 percent of trains in the northwestern state could be cancelled in very cold weather over the next few months, Deutsche Bahn (DB) chairman Rüdiger Grube told the Westdeutsche Allgemeine Zeitung newspaper on Thursday.
Currently the Datteln coal plant - scheduled to be decommissioned at the end of December - delivers three quarters of the electricity used DB trains in the state.
Electricity from the old coal plant guaranteed the smooth running of the rail network, especially on cold days, when its electricity demand skyrockets, said Grube.
"If decommissioning goes ahead and nothing happens, there's a big danger that the rail [network] could have bottlenecks in supply on very cold winter days in the morning," he warned.
"In such cases we have to take trains out [of service] to avoid the network collapsing. We discussed it with the board: it could be up to 30 percent of the train operation in NRW," he said.
The connection of Datteln IV, a replacement power plant, to the grid has been delayed by planning problems and has become stuck in a legal battle.
Meanwhile, Grube said DB was working on building converters to smooth out electricity supply from other sources for use by trains - which require a different frequency than households and industry.
But they would not be ready before until early 2014 and Grube has demanded plant operator E.ON be given an exceptional permit to continue running the older coal plant beyond the end of the year.