In 2018 Wales & Borders franchise was awarded to Keolis Amey Wales consortium, trading as Transport for Wales Rail Services, which will oversee a large investment into local rail services, including 36 CITYLINK UK Tram-Trains and 35 FLIRT trains. Of these ones, 11 will be diesel-operated and the other 24 FLIRT units will be tri-mode, capable of running on diesel, overhead electric wires and battery power.
The 36 CITYLINK UK tram-trains to operate on the Core Valley Line relying on 25 kV as well as battery power will be developed and manufactured by Stadler Valencia. The bidirectional three-car light rail vehicles cover tramway applications and full train regional operations at 100 km/h and have been adapted to the particularities of the network in South Wales Metro. With a length of 40 m and capacity for 257 passengers, the vehicles offer spacious, bright and air-conditioned passenger compartment with 6 multifunctional areas for bicycles or for PRM.
The use of batteries on tram-trains and tri-modes is an innovative and cost-effective way of providing a fully electric, environmentally-friendly service north of Cardiff by enabling ‘smart electrification’ of the infrastructure.