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This article investigates the feasibility of using regenerative energy from braking trains to charge electric buses in the context of New York City’s (NYC) subway and electric bus networks. A case study centered around NYC’s system has been performed to evaluate the benefits and challenges pertaining to the use of the preexisting subway network as a power supply for its new all-electric buses. The analysis shows that charging electric buses via the subway system during subway off-peak periods does not hinder regular train operation. In addition, having the charging electric buses connected to the third rail allows for more regenerative braking energy (RBE) to be recuperated, decreasing the energy wasted throughout the system. It was also found that including a wayside energy storage system (WESS) reduces the overall substation peak power consumption.
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Integration of solar technology into the electric railway system in dense urban regions
Abstract This paper investigates the deployment of solar technology throughout an electric railway system to accommodate tractive power needs. The approach is evaluated from both a technical and financial standpoint to better understand its overall feasibility. A case study is presented using New York City's subway system as the centre of deployment. As a means to both prevent excess voltages, as well as contribute to the city's shift to zero emission, parallel electric bus charging is also studied. It has been demonstrated that the proposed integration allows the subway system to still function without any hindrance to rail operation. The system is able to provide charging power for three to six electric buses per passenger station. In addition, the approach shows long‐term financial growth with average annual electric bill savings of approximately $50,000 per passenger station, each with a relatively short payback period of approximately 4 years.
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- Award ID(s):
- 1846940
- PAR ID:
- 10542461
- Publisher / Repository:
- DOI PREFIX: 10.1049
- Date Published:
- Journal Name:
- IET Smart Grid
- Volume:
- 7
- Issue:
- 6
- ISSN:
- 2515-2947
- Format(s):
- Medium: X Size: p. 904-916
- Size(s):
- p. 904-916
- Sponsoring Org:
- National Science Foundation
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