Charging Electric Vehicles Using Regenerated Energy from Urban Railways
Nowadays transport system is one of the most important producers of air pollution in cities. Urban railways and electric vehicle will play a fundamental role to accomplish the sustainability of cities. Urban railways are right now an efficient mode of transport. However it is necessary to continue improving its energy efficiency in view of the demand growth. On the other hand, electric vehicles need a charging infrastructure to support their market penetration. In this context, the use of the railway electrical infrastructure to charge electric vehicles could bring several benefits. First of all, there is a cost reduction effect because of the use of an existing installation. Besides, part of the regenerated energy that cannot be accepted by other trains can be used to charge electric vehicles, improving the efficiency of the global system. In this paper, a new system for the global energy management between the railway infrastructure and the electric vehicles is proposed. Besides, the global energy savings that can be obtained using railway electrical infrastructure to charge electric vehicles has been assessed.
Fixed energy storage technology applied for DC electrified railway (traction power substation)
The fixed energy storage system solves the problem of rising energy costs by reducing primary energy consumption. Without a fixed energy storage system, the energy generated by a breaking vehicle would be simply converted into waste heat by its breaking resistors if no other vehicles are powered simultaneously. Because, as a rule, such synchronization of breaking and powering cannot be coordinated, the energy storage system stores the energy generated during braking and discharges it again when a vehicle is powered. This greatly reduces primary energy demand in traction power substation. However, in addition to this energy saving, the energy storage system contributes to the reduction of CO2 emissions. The energy storage system also stabilizes the system voltage. This study introduces technologies of fixed energy storage system applicable for DC electrified railway in Japan, and describes new control method for energy storage system.
Trends in kiln drives
The heart of the cement plant is the rotary kiln, and continuous quality production of cement clinker depends on the continuous accurate performance of the rotary kiln drive.