scholarly journals An (slightly) innovative vehicle for urban ground transport

2020 ◽  
Vol 2020 (1) ◽  
pp. 1-13
Author(s):  
Maciej Kruszyna

The article presents a proposal for constructing a vehicle for urban ground transport using a tram system (current consumption from the catenary, separate tracks), but with the option of leaving the track and using batteries or charging stations. This will allow for temporary or target extension of existing routes and for bringing large-scale rolling stock to densely built-up housing estates. Based on the review of modern solutions, the thesis was formulated that the development of an (slightly) innovative vehicle is "at your fingertips." The possibilities of introducing new rolling stock were shown on the example of Wroclaw. Nevertheless, the proposed solution may also be attractive to other, at least Polish cities. Keywords: Tram; Trolleybus; Electric bus, Innovation

2020 ◽  
Vol 18 (1) ◽  
pp. 196-211
Author(s):  
M. A. Kudryashov ◽  
A. V. Prokopenkov ◽  
R. S. Ayriev

The article provides the results of an intermediate stage of research on development of a project to create infrastructure for operation of highly environmentally friendly electric vehicles. The transition to electric transport is one of the promising methods to solve the problem of emissions and achieve environmental goals. An electric bus is a relatively new type of rolling stock, requiring a balanced and objective justification for selection of certain possible options for technical, technological, economic and other aspects of organisation of its operation. To achieve the goal of developing a project to create infrastructure for operation of environmentally friendly electric vehicles, an initial analysis of legal acts, technical characteristics of electric buses and the parking and on route infrastructure approaches to organizing transportation by electric buses with various charging concepts was performed. The analysis of the concepts of charging electric bus batteries allowed to divide them into 5 classes and group into 3 groups according to charging speed. An analysis of the required infrastructure for operation of electric buses showed that conceptually there are 2 types of charging stations. The calculations and evaluation of various options for organizing operation of electric buses on a fixed route with various concepts of charging were performed. A necessary direction for further research is economic assessment of operation of electric buses with various charging concepts and the necessary transport infrastructure. The methods used include analysis, evaluation of previously performed analytical studies, legal acts and a synthesis of domestic and foreign experience.


Author(s):  
Slobodan Mitric

A recent study requested by a group of mayors representing the largest Polish cities is summarized. The study was to be used as input into local and national debates about future directions of urban transport development in the country. The wider context is that of a major political and economic reform, begun in the late 1980s, involving no less than a rapidpaced transition from socialism to capitalism, featuring large-scale downsizing of the public sector, privatization, and a redistribution of political and resource powers from the state to local governments. Among the downstream effects of these changes has been an increase in private car ownership and use and a reduction in the market share of urban mass transit modes from between 80 and 90 percent of nonwalk daily trips to 70 percent or less. For transit operators, now owned by local governments, this has meant an added financial pressure coming after a decade of underinvestment in infrastructure, rolling stock, and other equipment. Large numbers of unemployed, retired, or otherwise low-income travelers, another consequence of restructuring the economy, have made it difficult to improve cost recovery by increasing fares. Traffic growth has generated congestion, since the structure and size of urban road networks were predicated on low car use. An urban transport strategy is proposed to respond to these problems. Its main short-term objective is to have an affordable and socially and environmentally acceptable modal split. In the longer term, the objective is to use the demand response to a much-reformed price system as the principal guide to how infrastructure and services should evolve. The key features of the strategy are as follows: ( a) evolution toward market-supplied services by a mixed-ownership mass transport industry; ( b) treatment of urban road networks as public utilities, focusing on cost recovery through pricing; ( c) linkage of pricing policies for mass transport and individual transport modes, in line with second-best thinking, aiming to reduce and even eliminate subsidies for both modes; and ( d) reliance on internally generated revenue leveraged by long-term borrowing to finance sectoral investments. It is therefore a counterpoint to a strategy wherein mass transport is a state-owned monopoly, the use of urban roads is subsidized as is mass transport, infrastructure investment is the instrument of preference as opposed to pricing, and sectoral investments and operating subsidies are financed from tax-generated budgets.


Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6610
Author(s):  
Raka Jovanovic ◽  
Islam Safak Bayram ◽  
Sertac Bayhan ◽  
Stefan Voß

Electrifying public bus transportation is a critical step in reaching net-zero goals. In this paper, the focus is on the problem of optimal scheduling of an electric bus (EB) fleet to cover a public transport timetable. The problem is modelled using a mixed integer program (MIP) in which the charging time of an EB is pertinent to the battery’s state-of-charge level. To be able to solve large problem instances corresponding to real-world applications of the model, a metaheuristic approach is investigated. To be more precise, a greedy randomized adaptive search procedure (GRASP) algorithm is developed and its performance is evaluated against optimal solutions acquired using the MIP. The GRASP algorithm is used for case studies on several public transport systems having various properties and sizes. The analysis focuses on the relation between EB ranges (battery capacity) and required charging rates (in kW) on the size of the fleet needed to cover a public transport timetable. The results of the conducted computational experiments indicate that an increase in infrastructure investment through high speed chargers can significantly decrease the size of the necessary fleets. The results also show that high speed chargers have a more significant impact than an increase in battery sizes of the EBs.


Author(s):  
Beate Störtkuhl

Architecture and urban planning were facing great challenges during the Weimar Republic, given the difficult economic context of the time. The housing conditions in Germany had already been problematic prior to the First World War. In the Weimar Republic, their improvement was defined as a communal, not-for-profit task. New urban quarters emerged and a new urban infrastructure had to be created, while many historic urban cores changed into a ‘city centre’ dominated by business and consumerism. In the optimistic, euphoric situation of societal renewal after the war, many architects produced visionary projects. Yet at the same time, they had to develop pragmatic approaches for a cost-saving, industrialized type of housing construction. Large settlements in Berlin and in Frankfurt, or the experimental Weißenhof settlement in Stuttgart as well as the Bauhaus represented the ideas of an architectural avant-garde that was internationally connected. The protagonists of modernism, the so-called Neues Bauen, dominated contemporary coverage and contributed, once they had been forced into exile in 1933, to the global reach of this current. Yet in reality, architecture and housing construction in the Weimar Republic were not dominated by the Neues Bauen. They can rather be described as multiple modernity, which showed fluid boundaries and permeability between radical modernist forms and traditionalist elements.


2019 ◽  
Vol 9 (9) ◽  
pp. 1748 ◽  
Author(s):  
Amra Jahic ◽  
Mina Eskander ◽  
Detlef Schulz

The city of Hamburg has decided to electrify its bus fleets. The two public transportation companies in this city expect to operate up to 1500 buses by 2030. In order to accomplish this ambitious goal, both companies need to build an appropriate charging infrastructure. They have both decided to implement the centralized depot charging concept. Buses can therefore charge only at the depot and do not have the possibility for opportunity charging at intermediate stations. The load profile of such a bus depot is highly dependent on the charging schedule of buses. Without an intelligent scheduling system, the buses charge on demand as soon as they arrive to the depot. This can lead to an unevenly distributed load profile with high load peaks, which is problematic for the local grid as well as for the equipment dimensioning at the depot. Charging scheduling on large-scale bus depots is a relatively new and poorly researched topic. This paper addresses the issue and proposes two algorithms for charging scheduling on large-scale bus depots with the goal to minimize the peak load. The schedules created with the proposed algorithms were both tested and validated in the Bus Depot Simulator, a cosimulation platform used for bus depot simulations.


2013 ◽  
Vol 443 ◽  
pp. 273-278 ◽  
Author(s):  
Ceng Ceng Hao ◽  
Yue Jin Tang ◽  
Jing Shi

Large scale electric vehicles integration into power grid, as nonlinear loads, will pose inevitable impacts on the operation of power system, one of which the harmonic problem will affect the power quality greatly. Firstly, the article analyzes the characteristics of harmonic caused by electric vehicle charging. And then, the harmonic flow distribution is analyzed based on the IEEE standard node systems. During transient analyses, the electric vehicle charging stations connected to electric grid are represented as harmonic sources. Results show that structure and voltage grade of electric grid, capacity and access points of electric vehicle charging load will have different effects on harmonic problem. At last, a few conclusions are given for connecting electric vehicles to electric grid.


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