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Energy Management in the Railway Industry: A Case Study of Rail Freight Carrier in Poland


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Energy is crucial to economic development, but its production usually has a negative impact on the environment. This ambivalence leads to the need for methods to improve energy efficiency. Transportation is one of the largest global energy consumers. Therefore, improving the energy efficiency of transportation is crucial for sustainable development. The aim of this article is to show the limitations of energy management in railways, resulting from the model of market regulation. The question in this context is whether only technological methods can be used in railways to steer its energy efficiency, as is suggested by the existing research. Critical analysis, desk research and a case study of Polish railway undertaking were used to find an answer to the research question. The discussion of the results shows that the European regulatory system leads to greater complications in the field of energy management than in other global regions, where railways are also important for the economy. Due to these limitations, rail operators use indirect methods to measure energy efficiency. Results indicate that although energy efficiency improvements are being achieved, they are mainly due to organizational measures and not technological ones as could be expected based on previous research.
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Energy Management in the Railway Industry: A Case Study of
Rail Freight Carrier in Poland
Aleksandra Kuzior 1and Marek Staszek 2,
Citation: Kuzior, A.; Staszek, M.
Energy Management in the Railway
Industry: A Case Study of Rail
Freight Carrier in Poland. Energies
2021,14, 6875.
Academic Editors: David Borge-Diez
and Victor Manuel Ferreira Moutinho
Received: 14 July 2021
Accepted: 15 October 2021
Published: 20 October 2021
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1Department of Applied Social Sciences, Faculty of Organization and Management, Silesian University of
Technology, ul. Roosevelta 26, 41-800 Zabrze, Poland;
2DB Cargo Polska S.A., ul. Wolno´sci 337, 41-800 Zabrze, Poland
Energy is crucial to economic development, but its production usually has a negative
impact on the environment. This ambivalence leads to the need for methods to improve energy
efficiency. Transportation is one of the largest global energy consumers. Therefore, improving the
energy efficiency of transportation is crucial for sustainable development. The aim of this article
is to show the limitations of energy management in railways, resulting from the model of market
regulation. The question in this context is whether only technological methods can be used in
railways to steer its energy efficiency, as is suggested by the existing research. Critical analysis, desk
research and a case study of Polish railway undertaking were used to find an answer to the research
question. The discussion of the results shows that the European regulatory system leads to greater
complications in the field of energy management than in other global regions, where railways are
also important for the economy. Due to these limitations, rail operators use indirect methods to
measure energy efficiency. Results indicate that although energy efficiency improvements are being
achieved, they are mainly due to organizational measures and not technological ones as could be
expected based on previous research.
Keywords: energy efficiency; transportation; railway transportation
1. Introduction
Energy is essential for economic and social development, as well as for improving the
quality of life. We could no longer imagine the modern world without access to energy.
Ensuring energy security has become one of the fundamental tasks facing governments of
individual countries. The increasing demand for energy on the one hand and dwindling
resources of non-renewable energy sources on the other results in the need to acquire energy
from alternative sources and to increase efficiency of energy consumption in various areas
of the economy, agriculture and social life as well as appropriate energy management.
Energy efficiency is defined broadly as the ratio between output, services, goods or energy
and energy input (Directive 2006/32/EC) [
]. Energy efficiency should be considered in the
wider context of sustainable development. Global Action Agenda 21 (1992) [
]—the basic
document constituting the concept of sustainable development—defines major courses of
action to improve energy efficiency in business, agriculture, transport and other areas of
human activity.
One of the primary goals identified in Agenda 21 is to reduce the atmospheric impact
of the energy sector by developing environmentally friendly and economically viable
energy systems, based on renewable and clean energy sources, aimed at less pollution and
more efficient generation, transmission and distribution of energy. The changes should be
based on research into innovative green technologies and the transfer of environmentally
friendly energy technologies to developing countries. Agenda 21 also envisages increased
capacity for energy planning and management of an energy efficiency programme. Ground-
breaking in its proposals to double prosperity while halving natural resource consumption
Energies 2021,14, 6875.
Energies 2021,14, 6875 2 of 21
was the report “Factor Four”, prepared for the Club of Rome [
]. The authors of the
report argued that the Factor Four revolution is necessary and technologically viable [
Nowadays, many of the solutions described in the report have already been implemented,
although we still have not achieved satisfactory results.
Another report prepared for the Club of Rome, entitled “Factor Five. Transforming
the Global Economy through 80% Improvements in Resource Productivity”, was also
developed by a team of specialists led by E. U. von Weizsäcker and published in London
in 2009 [
]. “Factor Five” is a certain complement and extension of “Factor Four ”. Based
on the assumptions of “Factor Four”, the authors show that there is a real possibility to
achieve a five-fold improvement in resource productivity in key sectors of the economy,
i.e., construction, transport, industry and agriculture.
The first decade of the new millennium brought various technological solutions that
enabled the implementation of energy-efficient solutions. The awareness and approach
of entrepreneurs to environmental protection issues has also changed. As indicated by
the report entitled “The Business Case for the Green Economy. Sustainable Return on
Investment” [
], the development of green economy sectors (renewable energy, increased
energy efficiency, rational waste management, reforestation, development of integrated
water management, reclamation of dry areas and sustainable agricultural development)
has taken place. The report’s conclusion is that the green economy represents a business
opportunity, and green investments not only pay for themselves but also enable them to
succeed in the market. The report provides examples of positive rates of return on green
economy investments and shows that green investments are not only financially profitable,
but they also strengthen brand value and build a positive reputation of the company, which
in turn translates into financial profits [
]. The issue of energy efficiency is present in
almost all documents constituting the concept of sustainable development and programme
documents of the European Union. Attention is drawn to the issue of scientific advice to
decision makers in the area of sustainable development management and implementation
of energy-efficient technologies [
]. Energy efficiency has also been the subject of research
and scientific consideration for many years.
In the context of energy efficiency, numerous topics are addressed in the literature,
such as: issues related to green energy [
], and renewable energy sources [
] (including
photovoltaics [
] or the use of biofuels [
]), clean technologies for obtaining energy
from coal [
], optimization processes for obtaining energy from natural gas [
], a variety
of chemical reactions in the combustion of heavy fuel oils [
], as well as processes for
reducing CO2 and other greenhouse gases [19,20].
Compared to the previous research, in this article, we take a broader perspective and
include the influence of regulatory framework of railways as well as organizational mea-
sures that can be implemented in railway undertakings in order to steer energy efficiency
in this industry. The expected conclusion may be valuable for business as well as policy
makers. The legislative perspective gains a special meaning nowadays, as the United
Kingdom after having left the European Union is announcing revision of their regulatory
framework and renationalization of railways.
There is also a growing number of articles that discuss the use of mathematical
tools, numerical tools, artificial intelligence, and cognitive technologies to support energy
efficiency improvement [
], energy management processes [
] as well as the
role of managers in the management of energy supply companies [
]. Studies on energy
management are quite numerous.
Railway companies are usually described in scientific literature from the perspective of
economic efficiency [
], environmental efficiency [
], digital transformation of transport
processes [
] or railway transport safety [
]. It is certainly a worthwhile idea to adopt
solutions based on cognitive technologies and artificial intelligence [
] in the management
processes of railway enterprises and use them for energy efficiency programming.
There are only a few studies on energy efficient railway companies per se; nevertheless,
the authors emphasize the need to use innovative solutions to increase energy efficiency.
Energies 2021,14, 6875 3 of 21
They point out, for example, the need to add the topology of the electric system to the
data considered when designing the train trajectory [
], to use more efficient thyristor
control algorithms [
], to improve the performance of the train control system using
artificial intelligence technologies, deep reinforcement learning and imitation learning [
to identify the value of features that reduce energy consumption using Artificial Intelligence
tools [46].
Rail is considered as a low-carbon transportation mode. Besides the high level of
electrification, energy efficiency in rail transport is one of the main reasons for the low
carbon footprint of rail [
]. Railway infrastructure is perceived as a system good, con-
stituting a natural monopoly. Therefore, to ensure market conditions for the use of this
infrastructure, it is necessary to use at least partial mechanisms of regulation. Models of
regulation, introduced in different countries, influence energy management in railway
undertakings. The aim of this article is to show the limitations of energy management in
railway companies, resulting from the adopted model of market regulation and to indicate
the practical methods used by the participants in this market to improve their energy
efficiency and to obtain a positive environmental effect.
The deregulation of railways in Europe was intended to eliminate monopoly and
introduce market mechanisms. One of the main mechanisms of this deregulation, vertical
separation, is the separation of infrastructure managers from carriers. In conjunction with
the fragmentation of the railway system in Europe, it caused considerable complications in
the accounting of traction energy supplied to individual operators in individual European
Union countries. This hindered action aimed at improving the energy efficiency of railways
and individual railway companies operating in the deregulated market. It also caused
complications in the creation of a common European railway area, postulated by the
European Union. Previous research in the field of railway energy efficiency has focused on
technical aspects. The importance of activities related to the organization of the transport
process and the rolling stock maintenance system was not revealed. We believe that such
activities have a significant impact on improving the energy efficiency of the railway
operator. The effects of the railway regulatory model and its implementation in the
European Union countries on the energy efficiency of the railway system, as well as
practical problems arising during the construction of a single European railway area,
were also not revealed. This article, using the case study presented by DB Cargo Polska,
contributes towards closing the research gap in this regard.
2. Materials and Methods
The issue of energy management in rail transport is presented using a case study due
to its complexity and heterogeneity.
A case study is an empirical inference about a contemporary phenomenon in its natural
context. The method allows answers to the research questions “how?” (e.g., how something
is organized) and “why?” (e.g., why certain actions are taken). In-depth analyses also allow
for a thorough understanding of the described phenomenon [
]. A comprehensive ap-
proach was adopted, based on observation, analyses of internal documentation, statistical
data and other available source materials. Desk research analyses were also conducted,
referring to public statistics documents, reports, qualitative analyses and publications.
The case study is preceded by the analysis of the situation of the railway industry in
the world, Europe and Poland, where the company being the object of this study operates.
This analysis contains elements of comparison of conditions and the way the railway
industry is organized in particular geographical regions. These factors are important for
the differentiation of energy efficiency between particular regions. The taxonomy used
by the UIC—International Union of Railways—is adopted. The UIC is an international
professional association of railway companies, and its statistics enable comparison of data
concerning railways in different regions of the world, where rail plays an important role in
the economy.
Energies 2021,14, 6875 4 of 21
The choice of UIC statistics provides an appropriate context for railway performance
in Europe, which is a region where railways have their historical roots and have developed
intensively since the beginning of the 19th century [
]. The UIC data were obtained from
UIC reports and studies available online. They mainly relate to operational parameters.
UIC statistics are a valuable source of information due to the systematic presentation
related to the importance of railways for the economy. For infrastructure data, publicly
available data from Worldstat and Eurostat were used to show the level of development of
the railway network. They better reflect the global diversity of the railway network.
Our analysis also includes a comparison of energy efficiency aspects of rail transport
globally with its main competitor, road transport. UIC data were used in this regard, due
to the operational nature of these data.
With respect to railways in Poland, the analysis presents the development path of the
railway industry after the liberalization of the market in this country and the operating
conditions of companies, which, like the case study subject, are engaged in rail freight
transport. To conduct these analyses, a literature review was used.
3. Results
As we show in the analyses conducted in this chapter, rail is a mode of transportation
whose global environmental impact is relatively small. The diversity of the rail network
in global regions, the level of technological development, and specific market regula-
tions result in significant variation in energy efficiency and energy management methods
across regions.
3.1. Railways in Europe Compared to Other Regions
According to data published by the International Union of Railways (UIC) [
], rail
transport globally accounts for less than 2% of transport energy consumption, which is
about 0.5% of the total global energy consumption, with rail’s modal share being about
7%. Rail is in a much better position in terms of energy efficiency than road transport,
which is its main competitor in land transport. Road transport accounts for more than
75% of the total energy used in transport and its modal share is only 35%. If we assume
that the share of energy consumption represents the input and the modal share represents
the output of the system, then the global energy efficiency of rail can be evaluated in this
perspective as almost eight times higher than the efficiency of road transport. It should
also be noted that rail transport has significantly improved its energy efficiency in recent
decades, as indicated by data published by the UIC on decreasing unit energy consumption
on rail [
]. The density of the railway network in Europe is relatively high [
], as shown
in Figure 1. This has several structural effects that affect how railways in Europe operate
and how efficient they are. High network density results in numerous nodes and short
line lengths [
]. On the other hand, high network density favors the development of
intermodal transport, in which rail can play an important role by offering easy access to
transshipment terminals [52].
In addition, the European railway area is divided by numerous national borders,
which, given the diversity of infrastructure in terms of power supply to the catenary
network as well as signaling and safety systems, and in some cases the rail gauge, generates
additional constraints on railway traffic in Europe [
]. Comparing Europe, based on
data published by UIC, to other regions where rail plays a significant role in the transport
system [
], some interesting conclusions can be drawn. The modal share of rail is relatively
small in Europe. It amounts to 8% for passenger transport and 12% for freight transport.
As can be seen in Figure 2, the modal share of freight rail transport in the Russian Federation
is as high as 88%, and the modal share of passenger transport in Japan is 30%. On the other
hand, in the USA, the modal share of railway for passenger transport is less than 1%.
Energies 2021,14, 6875 5 of 21
Figure 1.
Density of railway network in km of railway lines per 1000 km
. Own study based on data
from [50].
An important distinguishing feature for railways in Europe is the share of renewable
energy in its energy mix. Europe compares best with other regions in this regard. However,
Figure 3shows that the total share of electricity in the rail energy mix is the highest in Japan.
In 2011, the European Commission published a White Paper entitled "Roadmap to a
Single European Transport Area" towards a competitive and resource-efficient transport
system. The paper calls for the creation of a transport system that will enable a 60%
reduction in greenhouse gas emissions by 2050 [
]. According to the report "Electrification
of the Transport System" published by the European Commission, one of the important
factors enabling the achievement of environmental goals set by the White Paper is the
reduction of unit energy consumption by rail transport by 30% by 2035 [55].
Commonly used measures of operational performance in rail transport are tonne-
kilometers, abbreviated as tkm and calculated as the product of weight and distance of
goods transport, and passenger-kilometers abbreviated as pkm and calculated analogously
as the product of the number of passengers and transport distance. In relation to these
performance units, expressing the output of rail transport, energy efficiency is calculated as
the ratio of energy consumption in a given period to operational performance achieved in
this period, expressed in tkm for freight transport, and for passenger transport, expressed in
pkm. The summary below in Figure 4shows how Europe is doing with its energy-efficient
rail targets compared to the achievements of other regions.
Energies 2021,14, 6875 6 of 21
Figure 2. Modal share of rail in selected regions in 2015. Own study based on data from [47].
Figure 3.
Share of energy sources in the energy mix of selected regions in 2015. Own study based on
data from [47].
Energies 2021,14, 6875 7 of 21
Figure 4.
Change of unit energy consumption in the rail industry in selected regions in 2015 vs. 2005.
Own study based on data from [47].
The progress in railway energy efficiency achieved by Europe was on a par with the
progress in the USA and Japan. A significant increase in specific energy consumption in rail
passenger transport in China can be explained by the dynamic development of high-speed
rail in that country.
The following factors can be a source of energy efficiency improvement on the railways
within the existing network [5658]:
reduction of the specific energy consumption of the traction vehicle while driving;
reduction of the energy consumption of the traction vehicle during standstill;
improvement of train driving technique by staff;
optimization of the timetable on the electrified network in order to balance the network load;
optimization of the rolling stock maintenance system, resulting in a reduction in
energy consumption;
reduction of energy used for the maintenance of the railway network and railway
power network.
Improving energy efficiency in individual regions can be achieved with very different
methods, due to the different energy sources used in these regions, which is shown in
Figure 3. In the USA, diesel traction is dominant. Actions aimed at improving energy
efficiency may include the technical development of the existing internal combustion en-
gines and the improvement of the technique of driving a combustion traction vehicle [
The importance of such activities for railways in Japan is marginal due to the dominant
electric traction there [
]. In turn, factors such as reducing energy consumption through
regeneration or optimization of timetables aimed at equalizing power consumption will
be of great importance in Japan [
]. In this context, the railway in Japan is similar to the
underground railway, which, operating in a closed system, allows the use of mathematical
algorithms for optimizing the timetable to improve energy efficiency [
]. The European
rail network lacks the advantages of both American and Japanese railways. There is a
large diversification in the field of energy sources, which means that sources of improving
the energy efficiency of traction vehicles should be sought in the development of electric
machines and internal combustion engines. Due to the high fragmentation of the infras-
tructure and the diversification of the power grid, optimization in terms of timetables is
currently not a practical possibility.
Energies 2021,14, 6875 8 of 21
The railway market in the European Union countries has been undergoing a process
of deregulation since the 1990s. Previously, railway in individual European countries were
organized as single monopolistic companies, controlling both infrastructure and railway
transport. However, the deteriorating position of railway in inter-modal competition with
road transport and the worsening financial condition of railway companies have led the
European Commission to take action aimed at revitalizing the railway and to search for
solutions introducing intra-modal competition in order to optimize use of the railway
infrastructure in Europe [
]. Elimination of the monopoly in railway transport turned out
to be a challenging task. The applied solution assumes the existence of system goods, which
are the subject of a natural monopoly [
]. In the case of the railway, the infrastructure is
considered to be such a goods system [
]. European deregulation of the railway market is
based on vertical separation, i.e., separation of operators (i.e., companies which operate
railway transportation) from railway infrastructure managers and establishment of rules of
free access of operators to infrastructure (still managed as a natural monopoly). In addition
to vertical separation, the deregulation of the European rail market has resulted in a
horizontal separation, which is based on separation of freight and passenger operators,
for which the regulations that are introduced assume separate licensing of operations.
The separation of infrastructure within the framework of vertical separation referred to
track infrastructure, along with related signaling, command, control and safety systems. It
also referred to the railway electrification system and its power supply system.
The Directive on Railway Vertical Separation was issued in 1991 [
]. The first rail-
way package, announced in 2001, gave guidelines for the allocation of railway network
capacity and charges for access [
]. Since then, rail market reforms have been successively
implemented in the member states, and successive packages have introduced detailed
regulations for rail transport in Europe, as shown in Figure 5below [68,69].
Figure 5.
European legal acts on the deregulation of the railway market. Own study based on [
By way of comparison, it should be added that the model of railway market deregula-
tion adopted for restructuring in the U.S. does not include the vertical separation, which
is the basic principle of European deregulation. The American model is based on geo-
graphical separation, separating individual segments of the railway network in such a way
that they are operated essentially by one operator. This model assumes that a particular
network is operated by a single operator and that competition occurs between alternative
networks offering connections between different regions of the country [
]. This choice
was influenced by several factors that differentiate the American rail system from the
European one. The lower network density, dominant private ownership of infrastructure,
Energies 2021,14, 6875 9 of 21
lack of the technical differentiation characteristics as well as the liberal approach of the
governments in Europe resulted in the fact that rail regulation, introduced by the Railway
Revitalization and Regulatory Reform Act of 1976 and the Staggers Rail Act of 1980, only
concerns the obligation imposed on railway operators to treat shippers using their rail
transport services in a non-discriminatory manner.
Taking into account the vertical and horizontal separation of the railways in Europe,
the effects of which were deepened by the emergence of numerous new players on the
railway market as well as the diversity of the systems of power supply to the railway
network among the individual countries of the European Union and often also within
those countries, the problem of accounting for the consumption of electric power supplying
the railway network is not a trivial one. On the one hand, in a locomotive connected to a
train, which travels between different power supply areas, the propulsion system must be
switched. Thus, the locomotive sequentially receives power from different networks during
a single journey. On the other hand, multiple locomotives belonging to different operators
operate simultaneously in a homogeneous network area. The power consumption of the
network has to be accounted for by multiple consumers. Furthermore, the decisions regard-
ing the timetables are taken by the infrastructure manager, which limits the possibilities
of the electric network manager to optimize energy consumption by balancing the power
demand over time.
Before the deregulation of railways in Europe, this problem did not occur on such a
large scale because monopolistic state-owned companies managed both the infrastructure
(including the track system and the power supply network for trains) and operations on this
network. Thus, there was no need to account for energy between sub-entities. Deregulation
conducted according to the U.S. model avoids the problem of complex energy billing
because the model still has only one operator on a segment of the network. Locomotives
manufactured before the deregulation of railways in Europe were generally not designed
for direct energy metering. Taking into account the life cycle of these vehicles, which is
often 40 to 50 years, for the next few decades we can expect to see locomotives equipped
both with and without metering devices on the European rail network. The issue of
standardization of on-board devices, measuring the energy consumption on the locomotive
and recognition of their measurements by individual managers of the railway power
network, still remains the subject of efforts of both the European Railway Agency (ERA)
and organizations associating managers of railway infrastructure [7173].
3.2. Railways in Poland Compared to Other European Countries
The railway network in Poland, according to the Office of Railway Transport (UTK),
which acts as the regulator in the country, had a length of 18,934 km in 2019, 61% of which
are electrified lines [
]. After Germany and France, Poland thus has the third largest rail
network in Europe. The network density in Poland according to UTK data reaches the
value of 62 km per thousand square kilometers. According to Eurostat data, the modal
share of rail in Poland for passenger transport in 2017 was 7.7%. As Figure 6below shows,
this share places the Polish railway at a level close to the European average, which for the
EU28 countries was 8% [75].
The modal share of rail in Poland for freight transport in 2017 was 26.8%. As Figure 7
below shows, this gives the railway in Poland a position well above the average for EU28
countries in this respect [76].
Energies 2021,14, 6875 10 of 21
Figure 6.
Modal share of railway transportation in passenger transport for selected European
countries in 2017. Own study based on data from [75].
Figure 7.
Modal share of railway transportation in freight transport for selected European countries
in 2017. Own study based on data from [76].
Such a high modal share of rail transport in freight transport in Poland, compared to
other EU28 countries, is mainly due to bulk coal transport in the country, which reflects the
role of this raw material in the Polish energy mix. Given the scale of coal haulage in Poland,
competition from road transport is limited in this respect. The negative dynamics of the
modal share of rail in the freight market shown in Figure 8below indicates that rail is not
benefiting adequately from the economic development of the country. The effects of this
development, in the form of an increase in freight transport, are consumed by other modes
of transport, mainly road transport. The modal share of railway in passenger transport has
remained constant during this period [75,76].
Energies 2021,14, 6875 11 of 21
Figure 8.
Dynamics of modal share of railway transportation in Poland. Own study based on data
from [75,76].
The demonopolization of the rail market was introduced in Poland in 2003. The law
governing the railway market was preceded by the Act on the Commercialization, Restruc-
turing and Privatisation of the State Enterprise Polskie Koleje Pa´nstwowe (Polish National
Railways—PKP), passed in 2000. On this basis, the former monopolist was restructured and
adapted to the requirements of the European directives contained in the first railway pack-
age. In Poland, a holding model has been adopted, in which the infrastructure manager and
the operators that formerly constituted the state monopoly are transformed into capitalized
companies but remain integrated within the holding company, which exercises ownership
functions over those companies. A similar model, but with varying levels of coordination
within the holding company, was used in the deregulation of railways in Austria, France,
Germany, Italy, Belgium, Slovenia and Latvia [
]. In 2015, a decision was made to sell
PKP Energetyka, a company belonging to the PKP holding, to the American fund CVC
Capital Partners. After the approval of the European Commission, the transaction was
finalized [
], and thus, the management of the power grid, supplying the railways in
Poland, was entrusted to a private company. Competition on the Polish railways appeared
as early as 2003. Even before deregulation, there were companies that operated railway
transport on separate lines, not belonging to PKP. These companies, having obtained li-
cences for railway transport, became fully-fledged market players [
]. In subsequent years,
new entrepreneurs appeared, obtained licences and started their transport activities. There
were also companies, controlled by national carriers from other European countries, which
started their business activity in Poland. According to the data of UTK, in 2020, 110 carriers
in Poland were licensed to carry out railway freight transport [
]. The emergence of new
players in the rail freight market results in a loss of market share by the national carrier.
However, intra-modal competition has not protected the freight railway in Poland from
the progressive loss of rail market share in inter-modal competition with road transport.
3.3. Energy Management in DB Cargo Polska
DB Cargo Polska has been present on the Polish market under the DB brand for more
than ten years and is one of the leading players in the rail freight market, but its roots go
back to the 1950s. It was then that the mining industry in Upper Silesia decided to set
up companies specializing in the rail transport of coal between mines, power plants and
coking plants located in the Upper Silesian industrial region, as well as in the haulage
of sand, which at that time was used to fill up depleted mine excavations. A separate
railway infrastructure network, belonging to the mining industry at that time, covering
the entire area of the Upper Silesian industrial region, was used for these transports.
Energies 2021,14, 6875 12 of 21
After the market liberalization in Poland in the 1990s, these companies were privatized
through employee share ownership or investment funds. The development impulse for
these companies was the deregulation of the railway market in Poland, which enabled
them to obtain rail transport licences and freely develop their business using the national
infrastructure, opened by the deregulation of the market also for alternative operators.
These companies have grown organically and through acquisitions, expanding nationwide
and building capital groups. Over time, these companies have also developed their
management systems, using the experience and drawing on models from the industry of
developed Western European economies [
]. Building increasingly complex corporate
structures, these companies also took steps to establish corporate governance tailored to
the scale of their operations [
]. At the beginning of the 21st century, attempts were made
to consolidate these companies—initially internally and later with the help of external
investors. Finally, at the end of 2009, they were purchased by Deutsche Bahn. At that
time, a group of 31 companies was bought and consolidated through a series of mergers.
Currently, DB Cargo Polska is part of the DB Cargo Group, which is a segment of Deutsche
Bahn responsible for the development of the rail freight business in Europe.
After the political reform and market liberalization in Poland in the 1990s, interest in
the concept of sustainable development and related corporate social responsibility emerged
among Polish enterprises [
]. DB Cargo Polska is a company which declares its orientation
towards sustainable development. Therefore, the optimization of energy consumption
fits well with the company’s strategy to ensure the achievement of both economic and
environmental objectives. The area of the railway company’s activity in which energy
consumption is the highest is, of course, transport operation. The company uses both
electric and diesel locomotives for this purpose for transport on non-electrified railway
lines. Diesel shunting locomotives are used for first-mile and last-mile operations associated
with sidings and terminals. Another area where the company consumes a relatively large
amount of energy is rolling stock maintenance. For this purpose, the company uses repair
facilities, which consume thermal and electrical energy. The remaining marginal part of
energy consumed by the company is related to its administrative activities.
Electricity used to power the locomotives is purchased from the network manager,
which in Poland is PKP Energetyka. This energy is a variable cost to the company, so its
consumption is proportional to the transport performance of the company. Due to the
problems with the direct accounting of electric energy consumed in the railway network
(described in previous chapters), the statistical method is used for settlements with PKP
Energetyka, which is based on the calculation of the company’s share in the total transport
performance of all carriers using the network in the settlement period. This method cannot
be completely avoided until all vehicles running on the network and using electricity are
equipped with on-board energy consumption meters approved by the power grid manager.
Statistical billing of electricity consumption, when operating, makes it impossible to calcu-
late the energy efficiency of a particular operator or a particular locomotive, since operators
are charged for electricity consumption derived from the average energy efficiency of
all operators that have used the network. The efficiency of the network itself (expressed
in the ratio of energy consumed by operators to energy purchased by the network man-
age) is also of relevance here. Finally, the grid itself generates energy losses connected
with its transmission as well as with the maintenance of transformer stations and other
power equipment.
Taking into account this limitation with regard to the accuracy of accounting for
traction energy consumption, DB Cargo Polska focuses on managing the overall energy ef-
ficiency of the company, understood as the relationship between the transport performance
and energy consumed by the company. Although transport performance is equivalent
to the company’s main product, the energy consumed by the company is also used for
additional services offered to customers as part of logistics or railway technology packages,
such as loading or unloading goods, servicing customer rolling stock or servicing the
railway infrastructure at a customer’s siding. Thus, the energy included in the company’s
Energies 2021,14, 6875 13 of 21
statistics contributes to the generation of additional output, which makes the actual energy
efficiency of the company higher than the results from the calculation based only on the
transport performance.
Therefore, the total energy consumption of the company consists of: (1) electric
energy consumed by locomotives while operating transport, which is charged by the
network manager based on the statistical method; (2) energy produced by generators of
diesel locomotives used by the company to operate transport and shunting at customer’s
sidings and terminals; (3) energy produced by fuel engines of other vehicles used by the
company; (4) electricity used to power machines in rolling stock repair plants and to light
the company’s property; (5) heat energy used to heat the company’s property. The graph
below shows the shares of the mentioned energy consumption components in total energy
consumption of the company in 2020.
As can be seen from the diagram in Figure 9, the largest share of energy consumption
in the company is that produced by diesel locomotive generators, and the total share of
energy consumed by electric and diesel locomotives reaches 87%. The larger share of energy
consumed by diesel locomotives than the electric locomotives (despite the electrification
of railways lines in Poland amounting to 61%) is explained by the inclusion of the work
of diesel shunting locomotives, used to perform the first and last mile transports as well
as shunting at sidings and customer terminals, where the amount of performed tonne-
kilometers is small in relation to the working time of the locomotive engine used to perform
them. The company has achieved a positive trend in the dynamics of performed tonne-
kilometers between 2012 and 2020. The graph below shows the dynamics of the transport
work in comparison with the dynamics of the total energy consumption in these years.
These two parameters allow to calculate the dynamics of the company’s energy efficiency.
Figure 9. Structure of energy use in DB Cargo Polska in 2020. Own study based on company data.
The break in the positive trend in 2020, shown in Figure 10, is due to the economic
collapse caused by the COVID-19 pandemic. The company improved its energy efficiency,
measured as the ratio of transport work to the total energy consumption of the company,
by more than 20% between 2012 and 2020. The additional output produced by using this
energy is not easy to operationalize, due to the variety of ancillary services sold. However,
it has been assumed that the measure of this output will be the value of revenues generated
by the company from services that do not constitute rail transport. The graph below shows
the dynamics of the company’s revenue from services that do not generate freight work.
Energies 2021,14, 6875 14 of 21
Figure 10.
Transport performance, energy consumption and energy efficiency of DB Cargo Polska,
normalized to 2012. Own study based on company data.
As we can see in Figure 11, revenues from ancillary services had positive dynamics
from 2012 to 2020, which means that the actual dynamics of the company’s energy efficiency
were higher than presented in Figure 10. In order to increase energy efficiency, the company
undertook a number of optimization and innovation projects in all areas of its activity.
The key area in which to look for potential savings in energy consumption is, of course,
the locomotive fleet. The company has been investing in this area since the start of its
activities within the Deutsche Bahn Group. The fleet of locomotives at the company’s
disposal after the takeover by DB consisted of electric locomotives whose average age
in 2010 was 45 years. These locomotives were gradually being phased out of service
and replaced with new electric locomotives which had the ability to regenerate electricity.
After ten years of operation, the average age of the electric locomotives used by DB Cargo
Poland in 2020 has decreased by 20 years. Taking the passage of time into account, this
gives an effective improvement in the age of the fleet of 30 years. The diesel locomotives
owned by the company in 2010 were gradually being replaced by newer-generation diesel
locomotives, which were available for transfer to Poland from the resources of the DB
Cargo Group in Europe. After ten years of functioning of the company, the average age of
diesel locomotives has increased by only 2 years, which gives an effective improvement
of 8 years. This information illustrates the scale of the modernization of the company’s
locomotive fleet. While the improvement in the quality of the company’s fleet of diesel
locomotives is reflected in the dynamics of the company’s overall energy efficiency shown in
Figure 10,
the improvement in the quality of the electric locomotive fleet is not, because the
statistical method of accounting for energy consumption with the network manager makes
it impossible to reflect the actual energy consumption of a particular operator.
Energies 2021,14, 6875 15 of 21
Figure 11.
Revenue from non-transport services of DB Cargo Polska, normalized to 2012. Own study
based on company data.
The environmental impact of electric locomotives used by the company is determined
not only by their energy efficiency, but also by the energy sources used by the network
manager. DB Cargo Poland therefore has no direct influence on what sources of energy
are used by electric locomotives belonging to the company. Looking for ways to reduce
the carbon intensity of its operations, in 2020, the company signed a letter of intent with
PKP Energetyka, which aims to enable the purchase of energy from renewable sources and
settlement of this purchase between PKP Energetyka and DB Cargo Poland. It should also
be mentioned here that the gradual modernization of the fleet resulted in a reduction of the
time spent on preventive and emergency maintenance of locomotives, thus reducing the
production reserve and improving the productivity of the fleet. In addition, the company
worked on the operational productivity of its fleet by reducing the waiting periods of
locomotives between successive train services. These actions—in addition to improving
financial efficiency—were also aimed at reducing unproductive energy consumption by
locomotives during waiting times. This is particularly important in the case of diesel
locomotives, which need to maintain proper engine temperature during periods of negative
temperatures, which result in fuel consumption. Figure 12 below shows the dynamics
expressed in tonne-kilometers per locomotive of the productivity of DB Cargo Poland’s
fleet of line locomotives used in 2012–2020.
Rolling stock maintenance is also an important operational area in terms of energy
consumption. The savings in thermal and electrical energy achieved by DB Cargo Polska
in this area result mainly from the restructuring it has undertaken and the process innova-
tions implemented as part of that restructuring. In 2012, the company had maintenance
workshops with a total roofed area of more than 101,000 m
. Work in these workshops was
organized mainly in the nest system, which resulted in the fact that the rolling stock stayed
for a long time in the plant, which resulted in a high demand for the space, on which repair
operations are performed. As the number of locomotives and wagons of older types was
reduced and their productivity improved, some plants were closed and properties were
sold. In 2013, a new wagon inspection repair system, organized in the pipeline system, was
implemented. This organization—based on lean manufacturing methodology, commonly
used in the automotive industry—had not been used in the rolling stock service before.
The introduction of this innovation has significantly shortened the time spent in the repair
shop and further reduced the amount of space used by the company for rolling stock
maintenance. By 2020, the company was using a total of less than 47,000 m
of covered
space to service its own rolling stock, while at the same time selling some of its production
Energies 2021,14, 6875 16 of 21
capacity to customers outside the company. Thus, the company reduced the size of its
repair facilities by 53% between 2012 and 2020.
In terms of administrative activities, the actions aimed at improving energy efficiency
came down to reduction of the used office space, thermomodernization of owned properties
and modernization of lighting.
Figure 12. Locomotive productivity of DB Cargo Polska in tkm per locomotive, normalized to 2012.
Own study based on company data.
4. Discussion and Conclusions
The energy efficiency of railways is globally much higher than that of its main com-
petitor, road transport. Despite the advantage in energy efficiency, as well as the European
Union’s policy declarations regarding the planned increase in the importance of railways,
in recent decades, railways have been losing market share in land transport to road trans-
port. Given the much lower energy efficiency of road transport, this has resulted in a
deterioration of the energy efficiency of the European transport system.
The European railway system is characterized by considerable complexity in compar-
ison to other railway systems in the world, i.a., due to different energy supply systems
of the network and national borders separating areas served by national railway network
managers. The opening of the railway market in Europe has increased this complexity
by introducing intra-modal competition. This results in a multitude of operators using
individual national networks and operating across national network boundaries. The lo-
comotive fleet in Europe is not completely equipped with on-board energy consumption
meters. As a consequence, network managers and operators need to deal with a lack of
transparency in settlements. Hence, we can conclude that numerous limitations exist for
optimization activities in the field of railway energy efficiency.
Railways in Poland still have a relatively large share in freight transport, which is
largely due to the high importance of coal in the country’s energy mix. Deregulation of the
railways in Poland has resulted in the emergence of a relatively large number of players in
the rail freight market.
DB Cargo Poland has been operating under the DB brand since 2010, but its legal
predecessors were providing rail freight services before the market liberalization in Poland.
Due to the lack of transparency in the energy efficiency of electric locomotives, the company
manages its energy efficiency mainly by using a global indicator of energy consumption
per unit of transport performance. Actions to improve the company’s energy efficiency
consisted mainly of improving the operational productivity of the locomotive fleet, mod-
ernizing this fleet, and optimizing the fleet maintenance process. Due to the problems with
transparency in accounting for energy consumed by electric locomotives, not all of the
Energies 2021,14, 6875 17 of 21
action taken could be reflected in the positive trend in energy efficiency recorded by the
company between 2012 and 2020.
Based on the literature review presented, the analysis performed, the business case
considered and the discussion above, the following conclusions can be drawn. The model
of rail transport market regulation introduced in the European Union has had a significant
impact on the energy efficiency of railways. This model has led to an increase in the
complexity of the billing system for electricity consumption. Limited transparency in
this respect leads to the use of the indirect energy efficiency management methods of
railway companies presented on the example of DB Cargo Polska, which makes it difficult
to assess the effectiveness of individual activities aimed at improving energy efficiency
as well as reducing the negative environmental impact by railway companies. The far-
reaching liberalization of the rail market in Europe, the purpose of which was to use market
mechanisms to improve the economic efficiency of European railways, has so far failed to
break the advantage of road transport, which still takes over most of the transport work
generated by economic growth on the European continent. This liberalization has led
to fragmentation of the railway system and economic optimization on the microscale of
individual enterprises. Due to the commercialization of the management of the power
network, presented on the example of the sale of PKP Energetyka, the company, acting
for its statutory goals, does not have to take into account the economic effects as well as
environmental effects that can be achieved, for example, by reducing energy consumption
for the benefit of grid maintenance, significant from the entire railway system. The example
of DB Cargo Polska also shows that despite the existing limitations, railway companies
undertake various activities aimed at improving their energy efficiency and are in a position
to demonstrate the combined effectiveness of their activities. Obtaining transparency in the
scope of the effects of individual activities without breaking the existing interoperability
barriers and unifying the billing system for electricity consumption in Europe seems to be
impossible, and the possibility of reducing electricity consumption in the railway system
by implementing optimization of timetables, as is the case in systems underground, seems
to be still unreachable.
Given the limited access to energy efficiency data for specific vehicles and individual
segments of the power grid, it would be advisable to undertake research by market
regulators who could access this type of data. It would also be interesting to study
the effectiveness of the electrification of the railway network or the unification of the
parameters of the current used in the European railway network, from the perspective of
railway energy efficiency.
Author Contributions:
Conceptualization, A.K. and M.S.; methodology, A.K. and M.S.; validation,
A.K. and M.S.; investigation, A.K. and M.S.; resources, A.K. and M.S.; writing—original draft
preparation, A.K. and M.S.; writing—review and editing, A.K. and M.S.; visualization, A.K. and
M.S.; funding acquisition, A.K. All authors have read and agreed to the published version of
the manuscript.
This research was funded by Department of Applied Social Sciences of the Faculty
of Organization and Management of the Silesian University of Technology, grant number 2021:
Data Availability Statement:
The following public data sources were used in the research. Available
online: (accessed on 14 April 2021).
Available online: (ac-
cessed on 14 April 2021). Available online:
0_rk310/default/table?lang=en (accessed on 14 April 2021). Data on the activities of the company
that is the subject of the case study were made available based on the data disclosure agreement.
Conflicts of Interest: The authors declare no conflict of interest.
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... Current changes in energy systems aimed at increasing the use of variable renewable energy have far-reaching consequences for all its elements [39][40][41]. Any segments of energy systems face new problems of security, flexibility, and capacity [42,43]. In the future, because of climate change and in the context of the energy transition, the entire electric power infrastructure may become more vulnerable to failures and will require an increase in its long-term security [44]. ...
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The article aims to identify the relationship between energy efficiency and particular indicators of energy losses in Europe. The results of the bibliographic analysis showed a knowledge gap in energy losses in Europe regarding the new challenges of energy security. For the analysis, annual panel data from 32 European countries were collected from 1990 to 2019. The authors used the Jarque–Bera test to assess the normality of the residuals, utilized the Breush–Pagan test for heteroskedasticity check, and applied regression analysis to determine the relationship between energy efficiency and energy loss rates in Europe. To assess the effects of energy losses, the authors performed OLS modeling using the stats model’s package in Python. According to the modeling results, an increase in distribution losses (% of available energy from all sources) by 1% in Europe leads to an increase in energy consumption by 17.16% under other constant conditions. There is significant heterogeneity between European countries concerning energy efficiency and energy loss coefficients. Such a situation requires the development of new strategies and mechanisms to reduce energy losses, considering the challenges of energy security in Europe in turbulent times. Further research can be devoted to clustering European countries according to the main groups of energy losses: in the extraction, distribution, storage, and transformation of energy.
... Kuzior and Staszen highlighted in [20] the limitations of energy management in railway companies, resulting from the adopted model of market regulation. They also indicated the practical methods used by market participants, so that the energy efficiency is improved and a positive effect on the environment is obtained. ...
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Increasing energy efficiency in electric transportation systems is a topical issue, considering the worldwide concern for reducing CO2 emissions, and especially through the significant reduction in energy loss and energy consumption [...]
... One of the areas of system theory is the dynamics of systems, representing a framework for analyzing and controlling complex feedback systems. These systems may be relevant to a wide range of disciplines, including business, economics, environmental studies, energy management, urban challenges, and other social and human concerns [41,42]. Business environments are changing and becoming increasingly competitive. ...
Contemporary challenges for development should involve a sustainable approach. One of the important sectors where such challenges are observed is transport. In a wide range of studies addressing environmental, social, and economic dimensions of sustainability, an approach that combines these dimensions as an integrated technique to assess sustainable development of passenger rail transport organizations is still lacking. The first aim of the presented research is to offer a relatively comprehensive collection of railway sustainability indicators as well as a novel causal loop. The second aim is to assess and improve sustainable management using a case study of a passenger rail transport company. To model the relationships inside and around the transport company, the system dynamics (SD) methodology was chosen, being the primary contribution of the study. Additionally, the Fuzzy-TOPSIS logic is required to find the most appropriate scenarios that may change future strategies by making them more socially and environmentally friendly. The proposed research may support experts in assessing sustainability management in transport companies and improve their performance considerably.
... In the report, it is stated that cognitive APM application has allowed an automotive manufacturer to reduce equipment downtime by 34 per cent and decrease equipment maintenance costs by 10 per cent [10]. Other examples are the successful cases of the AI predictive maintenance platform adopted by Nissan and smart sensor and advanced machine learning analytics applied by Deutsche Bahn [26,27]. The company claims an unplanned downtime reduction of 50% and a payback period of fewer than 3 months. ...
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Cognitive manufacturing (CM) provides for the merging of sensor-based information, advanced analytics, and cognitive technologies, mainly machine learning in the context of Industry 4.0. Manufacturers apply cognitive technologies to review current business metrics, solve essential business problems, generate new value in their manufacturing data and improve quality. The article investigates four powerful applications for cognitive manu-facturing and their influence on a company`s maintenance. The study aims to observe kinds of cognitive technol-ogy applications for smart manufacturing, distinguish their prospective gains for manufacturers and provide suc-cessful examples of their adoption. The analysis is based on the literature and report review. Assessment of the cases of technology adoption proves that cognitive manufacturing provides both enhanced knowledge manage-ment and helps organizations improve fundamental business measurements, such as productivity, product relia-bility, quality, safety, and yield while reducing downtime and lowering costs.
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The article deals with the impacts of economic, ecological, and social development scenarios in ensuring sustainable energy development. EU countries were the statistical bases of the study; the assessment period was from 2000 to 2019. The information bases of the research were the World Bank, the Organization for Economic Cooperation and Development, and the European Commission data. Based on the generalized method of moments, the authors investigated the dependence of energy consumption on economic, environmental, and social development factors. The results confirm the positive relationship between renewable energy consumption and GDP per capita, foreign direct investment, and energy depletion. A negative relationship between the consumption of renewable energy, CO2 emissions, and domestic gas emissions was proved. Based on intelligent data analysis methods (methods involving one-dimensional branching CART and agglomeration), countries were clustered depending on the nature of the energy development policy; portraits of these clusters were formalized. The study results can be useful to authorized bodies when determining the most effective mechanisms for forming and implementing sustainable energy development policies.
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This paper analyses the attitude of the contemporary philosophy to the problems associated with increasingly radical diagnoses concerning anthropogenic climate changes that may lead the human civilization on Earth to a global catastrophe. One can identify three approaches to this issue in contemporary philosophy: involvement in the breakthrough taking place; evaluation of the change process from an axiological perspective or ignoring the evolving phenomena on the grounds that it is not possible to define them meaningfully from the perspective of theoretical orientations that currently dominate the contemporary philosophy.
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The article aims to enhance understanding of how relations, behavior and attitude of the executives and contractors to achieving the objectives by energy supplying companies affect the efficiency of the latter’s overall development. There is offered a factor-reflexive approach to diagnosing the executives’ and contractors’ attitude to realizing the tasks of developing the energy supplying companies. This approach includes models to identify and analyze the factors that influenced the change in contractors’ behavior based on the combination of expert techniques, correlation and regression analysis and evaluation of the personnel response to organizational, resource and staffing projects development, through accumulating sufficient statistical information based on the enterprise’s features, relations and environment. This approach to diagnosing executives’ and contractors’ response to the implementation of tasks and the resulting changes takes into account the subjective component of their response. Practical implementation of this approach in monitoring the conformity of the development tasks has proven the ability to identify problems from the viewpoint of the task executives.
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Electricity is a vital resource for various human activities, supporting customers’ lifestyles in today’s modern technologically driven society. Effective demand-side management (DSM) can alleviate ever-increasing electricity demands that arise from customers in downstream sectors of a smart grid. Compared with the traditional means of energy management systems, non-intrusive appliance load monitoring (NIALM) monitors relevant electrical appliances in a non-intrusive manner. Fog (edge) computing addresses the need to capture, process and analyze data generated and gathered by Internet of Things (IoT) end devices, and is an advanced IoT paradigm for applications in which resources, such as computing capability, of a central data center acted as cloud computing are placed at the edge of the network. The literature leaves NIALM developed over fog-cloud computing and conducted as part of a home energy management system (HEMS). In this study, a Smart HEMS prototype based on Tridium’s Niagara Framework® has been established over fog (edge)-cloud computing, where NIALM as an IoT application in energy management has also been investigated in the framework. The SHEMS prototype established over fog-cloud computing in this study utilizes an artificial neural network-based NIALM approach to non-intrusively monitor relevant electrical appliances without an intrusive deployment of plug-load power meters (smart plugs), where a two-stage NIALM approach is completed. The core entity of the SHEMS prototype is based on a compact, cognitive, embedded IoT controller that connects IoT end devices, such as sensors and meters, and serves as a gateway in a smart house/smart building for residential DSM. As demonstrated and reported in this study, the established SHEMS prototype using the investigated two-stage NIALM approach is feasible and usable.
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The research explores the potential of digital-twin-based methods and approaches aimed at achieving an intelligent optimization and automation system for energy management of a residential district through the use of three-dimensional data model integrated with Internet of Things, artificial intelligence and machine learning. The case study is focused on Rinascimento III in Rome, an area consisting of 16 eight-floor buildings with 216 apartment units powered by 70% of self-renewable energy. The combined use of integrated dynamic analysis algorithms has allowed the evaluation of different scenarios of energy efficiency intervention aimed at achieving a virtuous energy management of the complex, keeping the actual internal comfort and climate conditions. Meanwhile, the objective is also to plan and deploy a cost-effective IT (information technology) infrastructure able to provide reliable data using edge-computing paradigm. Therefore, the developed methodology led to the evaluation of the effectiveness and efficiency of integrative systems for renewable energy production from solar energy necessary to raise the threshold of self-produced energy, meeting the nZEB (near zero energy buildings) requirements.
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This paper describes a methodology for implementing the state estimation and enhancing the accuracy in large-scale power systems that partially depend on variable renewable energy resources. To determine the actual states of electricity grids, including those of wind and solar power systems, the proposed state estimation method adopts a fast-decoupled weighted least square approach based on the architecture of application common database. Renewable energy modeling is considered on the basis of the point of data acquisition, the type of renewable energy, and the voltage level of the bus-connected renewable energy. Moreover, the proposed algorithm performs accurate bad data processing using inner and outer functions. The inner function is applied to the largest normalized residue method to process the bad data detection, identification and adjustment. While the outer function is analyzed whether the identified bad measurements exceed the condition of Kirchhoff’s current law. In addition, to decrease the topology and measurement errors associated with transformers, a connectivity model is proposed for transformers that use switching devices, and a transformer error processing technique is proposed using a simple heuristic method. To verify the performance of the proposed methodology, we performed comprehensive tests based on a modified IEEE 18-bus test system and a large-scale power system that utilizes renewable energy.
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The current approaches to estimating the level of energy security are based on applying a comprehensive approach to selecting the factors that affect energy security and the dynamics of processes in this domain. This article reveals the application of the model of energy security estimation and strategizing based on the systemic description of energy security as an object of management: the integral system, elements and connections, functions, processes, and the system’s material. At the same time, this model is able to take into account the dynamics of technological, political, economic, and other factors operating in the country and on the global arena. The energy security estimation model developed uses a modern methodology of integrated estimation: a multiplicative form of the integrated index, a formalized definition of the safe existence limits in order to provide scientific substantiation of the threshold vector, a modified rationing method, the principal components method, and the sliding matrix method to substantiate dynamic weighting coefficients. The paper demonstrates the systemic approach application to shaping strategic goals in the energy security domain in the context of sustainable development; the trajectory of energy security development is calculated by the method of strategizing that applies the principle “future is determined by the trajectory to the future” instead of the classical forecasting “past determines the future”. In general, the article shows the possibility of unifying the process of formalizing energy security (according to the needs of the researcher: country, industry, energy network, supply chain) as an object of management, estimating energy security status, and strategizing the regulatory sphere transformation in accordance with the target values for monitoring the effectiveness of management.
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The digital transformation of transport systems is one of the priority areas of the country’s strategic development, and requires joint participation and interaction of the state, transport industry enterprises, innovative companies - developers of new technologies and equipment. Constant price pressures and growing customer demands for product and service quality complicate the challenges faced by rail organizations. All these organizations, and first of all JSC Russian Railways, within the framework of the ongoing structural reform, cannot increase the efficiency of their activities using the traditional set of technological, organizational and management solutions to reduce costs for all business processes and divisions of the company. The current state of the Russian economy already allows us to note positive shifts in the field of digitalization. The digitalization of transport as one of the social sectors, the use of modern technical means and programs, makes it possible to increase the efficiency of the transport complex, to ensure high quality services. The authors considered digital technologies in JSC “Russian Railways” used to increase flexibility, efficiency and quality of service provision. The key electronic platforms used by Russian Railways in its work are presented. Disclosed telematic systems used in railway transport to improve safety. Methods are proposed for improving the quality of passenger service at railway stations in the Russian Federation.
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The paper presents an integrated assessment of the readiness to introduce technologies of the country’s digital economy on the infrastructure of the railway polygon. The authors consider the procedure for implementing a comprehensive scientific and technical project “Digital Railroad” developed by the Russian Railways holding company, and discloses the relationship of the digital railroad with the digital economy. The paper presents the main provisions of the concept, goals and technological solutions of the Digital Railroad project on infrastructure in the context of the implementation of the polygon principles for managing the transportation process. The SWOT analysis identified the risks and possible effectiveness of the implementation of the Digital Railroad project on the infrastructure. The concept of integrative management of the railway polygon infrastructure is formulated. Based on the theory of management of transport systems, the features and specifics of energy efficiency management were analyzed, which allowed using the classification and ranking procedures to develop a set of training mechanisms for energy efficiency in the field, allowing enterprises to reveal their own potential. The general algorithm of the simulation model of integrated assessment is formalized, summarizing the heterogeneous number of indicators and evaluation factors of polygon transportation management. The software for the formation of digital parameters for the safe operation of the infrastructure was implemented in the Automated Operational Management System for the Unified Infrastructure Management Center and was set up to transform the activities of industry organizations.
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Railway markets in Europe have been reorganized to allow competition between different operators. Thus, European railways have been vertically separated, separating infrastructure management from provisions of train services. This allows several train operators to compete for passengers and freight services. Different ways have emerged for vertical separation, capacity allocation and track access charges. This paper reviews, compares and discusses important deregulation aspects, using examples from a number of European countries to show different possible solutions. The study describes how competition has been introduced and regulated, with a particular focus on describing the different ways capacity is allocated and how conflicting requests by different train operators are resolved. It also reviews the related issue of how access charges are constructed and applied. Although guided by the same European legislation, we conclude that the studied railways have different deregulation outcomes, e.g., market organization, capacity allocation. Besides, few countries have so far managed to create efficient and transparent processes for allocating capacity between competing train operators. Although allowed by the legislation, market-based allocation is absent or never used. In order to foster more competition which can yield substantial social benefits, the survey indicates that most European railways still need to develop and experiment with more efficient and transparent capacity allocation procedures.
Energetic catalyst for electrochemical CO2 conversion into high value-added chemicals is critical. Herein, an ethynyl-linked cobalt(II) porphyrin conjugated polymer (PCP) is decorated on the carbon nanotubes (CNTs) to fabricate bi-metallic central electrocatalyst (CoCoPCP/CNTs) for electrochemical CO2 reduction (CO2 RR). By regulating the porphyrins’ central sites of the PCP, the resultant CoCoPCP/CNTs performs a high CO faradic efficiency of 94% with a TOF of 2.4 s⁻¹ at an extremely low overpotential of 0.44 V, which are much better than that of its CNTs-containing analogues. The effects of central site on the electrocatalytic performance and its mechanism are discussed based on the experimental study and theoretical calculation, and it is found that both of the Co centers in the four- and two-linked porphyrin units of the CoCoPCP are critical for CO2 RR. The present work should be of significance for the exploration of porphyrin-based conjugated polymers as energetic electrocatalyst in CO2 reduction.
Over the last few years, optimization models for the energy-efficient operation of railway traffic have received more and more attention, particularly in connection with timetable design. In this work, we study the effect of load management via timetabling. The idea is to consider trains as time-flexible consumers in the railway power supply network and to use slight shifts in the departure times from the stations to avoid too many simultaneous departures. This limits peak consumption and can help to improve the stability of the power supply. To this end, we derive efficient formulations for the problem of an optimal timetable adjustment based on a given timetable draft, two of which even allow for totally unimodular polyhedral descriptions. The proper choice of the objective function allows the incorporation of the priorities of either the train operating companies or the infrastructure manager. These include the avoidance of large peaks in average or instantaneous consumption and the improved use of recuperated braking energy. To solve the arising optimization models efficiently, we develop specially tailored exact Benders decomposition schemes that allow for the computation of high-quality solutions within a very short time. In an extensive case study for German railway passenger traffic, we show that our methods are capable of solving the problem on a nationwide scale. We see that the optimal adjustment of timetables entails a tremendous potential for reducing energy consumption.