Developing nuclear power stations must be considered if rail is to have a low carbon electricity supply, Association of Train Operating Companies boss George Muir has claimed.
Mr Muir said his personal view was that nuclear power would be needed because conventional electricity generation was not green enough, and renewable sources would not be able to produce sufficient power.
He was speaking at a Railway Forum conference on sustainable development, which heard how train operators were cutting their carbon emissions by reducing electricity use and using regenerative braking.
Mr Muir said c2c had experienced a dramatic drop in energy use since it switched to regenerative braking, which returns power to the network. c2c said later its electricity bill had fallen by about 16 per cent since regenerative braking was introduced in March.
The company is due to formally announce that its entire fleet is regenerative later this month, and in June, one of its Electrostars will be exhibited in London on World Environment Day.
Mr Muir told the conference the industry also had to pay attention to how its electricity was generated.
"Achieving a low carbon supply is crucial and if it is not achieved it is disastrous for rail," he said.
Mr Muir also said all money raised from the 'green taxes' being proposed by both parties should be used for environmental purposes.
"All the money raised should be spent on promoting green issues. It is a bizarre argument that green taxes have merit even if they are not spent on improving the environment."
Nick Coed, head of environmental strategy for National Express Group, which runs c2c, told the conference the group achieved a 17 per cent improvement in energy use in its depots last year. It estimated that the net savings in energy from customers choosing to use its services instead of car or air was enough to power 100,000 homes, or a city the size of Worcester.
Chief executive Richard Bowker had proposed a 'Carbon Club' loyalty scheme where customers would be rewarded with credits equivalent to the energy they saved by taking public transport instead of the car.
The club could offer credits in the form of upgrades or free coffee. Conservative shadow rail minister Stephen Hammond told the conference that his party's strategy would include some electricity generation from nuclear sources.