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SRS: Innovative, safe and automatic charging for trams and electric buses


SRS at a glance

  • Compact ground-based charging solution
  • Eliminates masts and overhead wires
  • Compatible with any vehicle dimensions (including double-decker buses)
  • Safe, automatic and rapid charging

Building on 15 years of expertise acquired from the development of APS technology, Alstom extends its feeding systems portfolio with SRS, a conductive ground-based static charging system for trams or electric buses equipped with on-board energy storage.

Clear skies for cities

SRS is a technological breakthrough in electric public transport, enabling city authorities to operate clean, quiet electric fleets without unsightly or obstructive catenary masts and overhead lines. This is an added advantage for cities with exceptional architectural heritage or constraints such as narrow streets or bridges, where overhead infrastructure is unsuitable or unfeasible. The charging system can be used at stops and also at line terminuses, in particular for electric buses which can fully recharge in the space of a few minutes.

Construction of a new tramway line with SRS, Nice ©Alstom / TOMA - David Richard
Construction of a new tramway line with SRS, Nice ©Alstom / TOMA - David Richard

Fast and unobtrusive

Power is supplied through a conductive device (rails or pads) embedded in the road or track surface at the bus or tram stop. When the vehicle is stationary over the device, a current collector shoe lowers automatically and makes contact to charge the battery. In tramway operation, this process takes no longer than 20 seconds – ordinary dwell time -, causing no delays to services. A compact solution, SRS blends invisibly into the cityscape.

km of tramway in Nice to be powered using SRS
years of commercial service with APS