Swiss rolling-stock manufacturer Stadler has won a contract to supply 36 CityLink tram-trains and 35 FLIRT (Fast Light Intercity and Regional Train) multiple-unit trains for the Wales & Borders franchise and the planned South Wales Metro.

The contract was signed with Keolis Amey Wales Cymru, which will take over both franchises for 15 years from 14 October.

The three-section CityLink tram-trains will operate on the lines from Cardiff to Treherbert, Aberdare and Merthyr Tydfil in dual mode, powered by either overhead electrification or batteries — marking the return of trams to the streets of Cardiff for the first time in more than 70 years.

Eleven of the FLIRT trains will be diesel-operated and used on South Wales Metro services to Maesteg, Ebbw Vale and Cheltenham.

The other 24 will be tri-mode, capable of running on diesel, overhead electric wires and battery power; there will be seven three-car trains and 17 four-car trains.

They will be used on routes linking the Vale of Glamorgan and destinations north of Cardiff. They will be powered by electricity to the north of Cardiff and diesel to the south, providing a cross-city connection.

The use of batteries on tram-trains and tri-modes is a cost-effective solution that will provide a fully electric environment-friendly service north of Cardiff, by enabling ‘smart electrification’ of the infrastructure, minimising the need for costly bridge modifications.

Trains will be longer and have more seats, which have been ergonomically designed to maximise passenger comfort. Each seat will be fitted with power sockets, and there will be air-conditioning throughout.

Noise and vibration will be kept to a minimum, with the new trains quieter than the current ones.