Batteries will play a vital role at the heart of the Siemens Sitras HES (hybrid energy storage) system, which will provide fully autonomous operation in trams, without the use of overhead lines.
Siemens' Rail Systems business unit is building this new tram system as a turnkey project, comprising 19 double-articulated tram units running over 11.5 km of track and serving 25 stations and stops in Doha University City. The system operates without the need for a pantograph and overhead lines, utilizing efficient regenerative braking and rapid charging at each stop. This will make Doha's system the most modern tramway in the world and establish the "Avenio concept" as a model for sustainable development of rail mass transit that reduces both visual impact and CO2 emissions.
The Sitras HES system for Doha's trams will combine Saft Ion-OnBoard®'s latest-generation regenerative traction lithium-ion batteries with a dual-layer capacitor system that ensures optimal energy balance. This approach provides rapid charging during the short stay at each tram stop, along with efficient regenerative braking that reduces energy consumption by 30%, allowing the trams to operate continuously throughout their daily service.
Doha's tram system will begin service in the fall of 2016.
Ion-OnBoard® Regen batteries are designed to meet the needs of railway equipment manufacturers and operators for both high power and energy density, combined with high charge and discharge rates. Furthermore, the use of maintenance-free lithium-ion cells, along with an advanced Battery Monitoring System and Management Software (BTMS), gives the operator complete visibility into the battery's status. This minimizes maintenance and contributes to an overall battery system that ensures maximum availability. Saft is the official supplier of the regenerative traction battery for the Doha project, providing a pre-assembled solution ready for installation on the tram roof.
