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.
Simulation of Electric Vehicle Charging Points Based on Efficient Use of Chargers and Using Recuperated Braking Energy from Trains
Electric vehicles represent an innovation in mobility that can help significantly reduce greenhouse emissions and mitigate climate change. However, replacing internal combustion with electric vehicles is not enough. This replacement needs to be complemented with a change in the energy mix of individual countries towards renewable energy sources and efficient use of electricity generated as a secondary product. Recuperative braking energy from trains can serve as one source of such secondary energy. Following an analysis of recuperative energy generated and analysis of charging requirements of individual electric vehicles, the paper proposes a model of a charging site near train stations. Using this energy to charge electric vehicles helps to reduce energy consumption from the electricity grid and thus reduce carbon emissions. Compared to other articles, the proposed model ensures the efficient use of recuperative braking energy from trains by using the variable charging power function; thereby, the installation of additional battery storage is eliminated. Our model results show that the benefits of a car park with a reservation system near train stations increase the car park efficiency, provide a sufficient number of private charging points, contribute to efficient use of recovered energy, and reduce carbon emissions.
Fast Response Energy Storage Systems
Fast Response Energy Storage describes several technologies characterized by the ability to provide or to absorb a high amount of electrical energy in a short period of time without diminishing the life time of the storage device. Major technologies discussed in this chapter are: Electric Double Layer Capacitors (EDLC) that store energy in the electrical field of a capacitor; Flywheels that do it as kinetic energy and Superconducting Magnets (SME) where energy is kept in the magnetic field of a lossless inductor. All these technologies can develop a wide range of different applications. In this way, they can support an increasing level of renewable energy sources penetration in the conventional grid by providing the necessary features. The most important are: Power quality issues, including grid frequency regulation and grid voltage stability; Smart grids development, including hybrid energy storage systems, like EDLC plus batteries, that support short-term and long-term necessities of the grid and electrical and hybrid vehicles as distributed energy storage systems. In this chapter, the basics for these technologies are presented, addressing information about the power converters needed to manage the energy of these devices. Besides, the most important applications regarding renewable energy integration are described, providing information about implemented real systems.