Ground-level Power Supply: New Innovation in Light Rail Technology

groundlevelpowersupplyA new cutting-edge technology is emerging in the world of light rail travel, ground-level power supply or APS. APS is a way to power light rail trams without the use of catenary or overhead power lines. The new technology utilizes a third rail line, placed in the ground between the running rails, to power the trams.
Each tram has power collection boxes with antennas that send radio signals to power the rail segments as the tram passes over them. When the approaching tram is detected, the segment below the tram is automatically energized. Conversely, when the tram leaves that section, the segment is de-energized and it is safe again for cars, pedestrians and bikes to cross the tram rails.

The technology was first introduced in Bordeaux, France with the opening of their Tramway de Bordeaux in 2003. Until 2011, Bordeaux was the only place this ground-level power supply was being utilized. The technology can now be found powering light rail systems in Reims, Orleans and Angers, France and Dubai.

Light rail trams typically run on catenary lines which transmit electrical power via the overhead lines to the trams. APS allows power to be transmitted via segmented street-level rail embedded between the running rails on the axis of the track.
Utilizing APS rather than overhead power lines, enables cities to preserve the aesthetics of the city, reduces the rail system’s footprint by eliminating poles, and optimizes safety and operational reliability. Other benefits to utilizing APS include:
• Preservation of historic sites, trees along the track and the overall urban environment
• Unlimited power supply (as opposed to power storage systems)
• Compatibility with all types of road surfaces
• Easy extension of the system if the line is extended
• High availability for optimum operational performance due to the simplicity of the concept, inspired by power supply rails used in metros
• Proven resilience, both in degraded mode and disrupted conditions of service (traffic jam at intersection for instance)
• Total safety for passengers, pedestrians and road traffic