A NEW fleet of express trains to replace First Great Western's 30-year-old InterCity 125 High Speed Trains will be lighter, greener and carry up to 70 per cent more passengers, the Government said.

Laying down specifications for the new trains, which will enter service from 2015, the Department for Transport said the diesel-powered version for FGW routes would need to be up to 35 per cent more energy-efficient and will have to be lighter to reduce wear and tear on the tracks.

Electric-powered variants for other routes will have to be up to 40 per cent more efficient.

The DfT said the new fleet, of between 850 and 1,500 coaches, would also have to be easily adaptable to cover both commuter and long-distance services.

Three consortia will compete to win the contract to develop and build the trains, with bids due in next summer.

The contract will be awarded in the winter of 2008-9, with testing of prototypes due to start in 2012.