Assessment and Recommendations for a Fossil Free Future for Track Work Machinery

Current railway track work machinery is mainly operated with diesel fuel. As a result, track maintenance of Austrian Federal Railways (OeBB) amounts to nearly 9000 t CO2 equivalent per year according to calculations from Graz University of Technology. OeBB’s total length of railway lines only accounts for 0.56% of the world’s length of lines. This indicates huge potential for mitigating greenhouse gas emissions considering the need for track maintenance worldwide. Environmental concerns have led to the introduction of alternative drives in the transport sector. Until now, R&D (Research & Development) of alternative propulsion technologies for track work machinery has been widely neglected. This paper examines the possibility of achieving zero direct emissions during maintenance and construction work in railways by switching to alternative drives. The goal is to analyze alternative propulsion solutions arising from the transport sector and to assess their applicability to track work machinery. Research results, together with a calculation tool, show that available battery technology is recommendable for energy demands lower than 300 kWh per construction shift. Hydrogen fuel cell technology is an alternative for energy demands higher than 800 kWh. For machinery with energy requirements in between, enhancements in battery technology are necessary and desirable for the coming years.

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Comparative TCO Analysis of Battery Electric and Hydrogen Fuel Cell Buses for Public Transport System in Small to Midsize Cities

Energies ◽

10.3390/en14144384 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4384

Author(s):

Hanhee Kim ◽

Niklas Hartmann ◽

Maxime Zeller ◽

Renato Luise ◽

Tamer Soylu

Keyword(s):

Fuel Cell ◽

Transport System ◽

Public Transport ◽

Transport Sector ◽

Hydrogen Fuel Cell ◽

Hydrogen Fuel ◽

Fuel Cost ◽

The Public ◽

Public Transport System ◽

Bus Body

This paper shows the results of an in-depth techno-economic analysis of the public transport sector in a small to midsize city and its surrounding area. Public battery-electric and hydrogen fuel cell buses are comparatively evaluated by means of a total cost of ownership (TCO) model building on historical data and a projection of market prices. Additionally, a structural analysis of the public transport system of a specific city is performed, assessing best fitting bus lines for the use of electric or hydrogen busses, which is supported by a brief acceptance evaluation of the local citizens. The TCO results for electric buses show a strong cost decrease until the year 2030, reaching 23.5% lower TCOs compared to the conventional diesel bus. The optimal electric bus charging system will be the opportunity (pantograph) charging infrastructure. However, the opportunity charging method is applicable under the assumption that several buses share the same station and there is a “hotspot” where as many as possible bus lines converge. In the case of electric buses for the year 2020, the parameter which influenced the most on the TCO was the battery cost, opposite to the year 2030 in where the bus body cost and fuel cost parameters are the ones that dominate the TCO, due to the learning rate of the batteries. For H2 buses, finding a hotspot is not crucial because they have a similar range to the diesel ones as well as a similar refueling time. H2 buses until 2030 still have 15.4% higher TCO than the diesel bus system. Considering the benefits of a hypothetical scaling-up effect of hydrogen infrastructures in the region, the hydrogen cost could drop to 5 €/kg. In this case, the overall TCO of the hydrogen solution would drop to a slightly lower TCO than the diesel solution in 2030. Therefore, hydrogen buses can be competitive in small to midsize cities, even with limited routes. For hydrogen buses, the bus body and fuel cost make up a large part of the TCO. Reducing the fuel cost will be an important aspect to reduce the total TCO of the hydrogen bus.

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Model of a prototype vehicle powered by a hybrid hydrogen system

Journal of Physics Conference Series ◽

10.1088/1742-6596/2130/1/012002 ◽

2021 ◽

Vol 2130 (1) ◽

pp. 012002

Author(s):

M Gilewski ◽

J Czarnigowski ◽

J Hunicz ◽

K Dubeński ◽

M Szafran ◽

...

Keyword(s):

Fuel Cell ◽

Energy Flow ◽

Control Strategies ◽

Model Identification ◽

Electrical Energy ◽

Hydrogen Fuel Cell ◽

Hydrogen Fuel ◽

High Agreement ◽

Electric Drive System ◽

University Of Technology

Abstract The paper presents a physical mathematical model of the movement of a prototype vehicle equipped with an electric drive system powered by two sources of hydrogen fuel cell and supercapacitors. The model is based on the analysis of the forces acting on the vehicle during motion, taking into account both resistance to motion and propulsion. The model also considers the flow of electrical energy from two sources: a hydrogen fuel cell and supercapacitors, taking into account energy buffering. The aim of the model was to develop a tool to analyse fuel consumption at different control strategies of energy flow in a vehicle. The paper also presents the results of model identification for the Hydros prototype vehicle developed at Lublin University of Technology for the Shell Eco Marathon competition. Model validation was performed for a selected run during the 2019 London competition. High agreement of the model with the results of the actual vehicle was obtained.

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