Conditions of Decision-Making Related to Implementation of Hydrogen-Powered Vehicles in Urban Transport: Case Study of Poland

Abstract

The changes in geopolitical and ecological conditions brought about the need to use environmentally friendly sources of vehicle power. This impacted the accelerated activities related to the use of hydrogen fuel in transport means. Based on the observations carried out in the countries of Central and Eastern Europe, it was found that the process of implementing hydrogen-powered vehicles in public transport is connected with difficulties faced by transport companies with regard to the purchase of these transport means. This study aims to analyse the conditions for making decisions regarding the implementation of hydrogen-powered buses in urban transport. A case study was considered, and the factors influencing the decisions related to the application of hydrogen-powered buses in Poland were analysed. The survey method was used to carry out the research. A questionnaire was developed, and the survey was conducted among representatives of transport companies that provide public transport services in Polish cities. As a result of the research, it was found that city authorities play a key role in deciding on the implementation of hydrogen-powered buses. The highest ranks among the proposed criteria influencing the decision on the purchase of hydrogen-powered buses were the economic ones. The concerns and benefits resulting from the potential purchase of hydrogen-powered buses were also examined. It was revealed that the decision to buy buses is most influenced by factors such as ensuring access to hydrogen and its price. The recommendations for transport companies and city authorities were formulated.

1. Introduction

The energy crisis and changes in geopolitical conditions have intensified activities related to the search for ecological sources of vehicle power. This, in turn, contributed to the intensification of research on the use of hydrogen as a fuel in transport means, including those used in urban transport. It can be stated that public transport may be a precursor to the use of low-emission drives in road transport. This is due to the need for entities involved in urban transport to implement national and international provisions on greenhouse gas emissions and environmental protection [1].

There is a growing number of examples showing practical applications for these vehicles in various European cities. Hydrogen-powered buses are already used in Western European countries, including Germany, the United Kingdom (UK), the Netherlands, Italy, Austria, and others. The implementation of hydrogen-powered vehicles, especially buses, in public transport services in the countries of Central and Eastern Europe, including Poland, is also observed. However, these are few cases because their purchase and commissioning are associated with numerous difficulties that transport companies have to face.

Hydrogen-powered buses have zero emissions, which is their most important asset in the context of taking care of the environment. Still, their acquisition and operation are associated with a number of problems. These include, among others, the high costs of purchasing and operating the buses [2], which are much higher than in the case of electric ones. In addition, providing access to hydrogen and a competitive purchase price may be decisive for changing the structure of the city bus fleet to hydrogen-powered. Furthermore, the specificity and economic conditions of the state affect the decisions made by transport companies regarding the purchase of hydrogen-powered vehicles. Companies that want to implement this type of bus are not always able to make their own decisions and bear the costs of purchasing the vehicles, as this process is complex and usually involves several decision-makers.

The analysis of the available subject literature revealed that most of the studies investigated the technical, operational, and economic issues related to hydrogen technology and hydrogen-powered vehicle operation. Based on a conducted literature review, a research gap was identified that deals with the need to investigate transport companies’ viewpoints on the conditions for making decisions on the purchase and implementation of hydrogen-powered buses. In the available studies, there is also a lack of comprehensive assessment of the benefits and concerns of the implementation of these buses in urban transport, taking into account the practitioners’ viewpoint.

The aim of this study was to analyse the conditions for making decisions regarding the implementation of hydrogen-powered buses in urban transport. The specific objectives were related to the identification of:

• entities that decide on the implementation of hydrogen-powered buses in urban transport,
• criteria that influence the decision to purchase hydrogen-powered buses,
• factors that influence the decision to purchase hydrogen-powered buses to a greater extent,
• benefits and concerns of implementing hydrogen-powered buses, as perceived by transport companies’ representatives.

A case study of transport companies operating in the Polish market was considered. The criteria and factors influencing decisions related to the implementation of hydrogen-powered buses in Poland, as well as the related benefits and concerns, were identified. A questionnaire was developed, and a survey was carried out among the representatives of transport companies operating in Poland to examine their opinions on the implementation of hydrogen-powered buses. Then, the research results were analysed, and conclusions were drawn. It was possible to identify the entities that decide on the implementation of hydrogen-powered buses in urban transport, as well as create rankings of examined criteria, factors, benefits, and concerns of implementing hydrogen-powered buses in urban transport.

The article includes a Section 2, where the aspects related to hydrogen-powered bus implementation were examined, including organisational and legal, economic, ecological, and social, as well as those related to the decision-making process. The Section 3 includes a description of the case study and the method chosen to conduct the research. The findings obtained from the analysis of the data collected using the questionnaire survey are presented in the Section 4. In the Section 5, recommendations to support the decision-making process for the deployment of hydrogen-powered buses in public transport are proposed. The Section 6 was developed to summarise the research results achieved.

2. Literature Review

2.1. Hydrogen Technology Development

In available scientific studies in the field of alternative energy sources, hydrogen is considered as the fuel of the future, which may be an alternative to the current energy system [3]. Hydrogen technology is becoming increasingly important in many areas of the economy. Undoubtedly, two main areas of its application can be distinguished, i.e., the industry [4,5] and the accompanying transport [6]. Efforts aimed at the development and application of hydrogen technologies are also strongly visible in the transport sector in relation to all its branches [7,8,9]. In scientific publications referring to the development of industry, hydrogen is indicated as a future energy source, which is in line with, among others, the assumptions contained in the “Paris Agreement” [10] concerning clean technologies [11,12].

Hydrogen technology is developing very intensively. Dimou et al. [13] presented the possibility of developing an energy-generating system (from a combined system using solar and wind energy) for heating and mobility on the Greek island of Anafi. The authors of this article designed an energy production system that, together with the electrolyser, will enable the use of the resulting surplus energy for the production of hydrogen for the purpose of powering the island’s public transport. Moreover, Sorensen and Spazzafumo [14] emphasised the versatility of hydrogen as a fuel, confirming the possibility of using microbiological fuel cells in transport and power plants. Other sources also confirm that there is a very rapid development of hydrogen energy technology. There are opinions that hydrogen may become the main fuel used in vehicles [15,16,17]. One of the important issues noticed is the access to hydrogen as a fuel. Grey, blue, and green hydrogen are distinguished [18].

However, the development of hydrogen technology and the implementation of hydrogen for fuelling transport means, e.g., buses used in urban transport, deal with a number of challenges. These challenges may be related to organisational, legal, technical, operational, economic, social, and environmental aspects.

2.2. Organisational and Legal Aspects

The implementation of hydrogen as a fuel in urban transport vehicles is conditioned by the commitments of the “Paris Agreement” [10] or the “Fit for 55” [19] package that significantly impacted the perspective given to clean technology implementation.

The “Fit for 55” project adapted by the European Union (EU) is an activity in the field of using hydrogen as an energy source. This is a proposal for a legislative package containing 13 drafts of specific regulations, aligning EU law with the achievement of the assumed climate goal, which is to reduce carbon dioxide emissions by 55% by 2030, compared to 1990. However, the ultimate objective of “Fit for 55” is to achieve climate neutrality by 2050 [19]. The introduction of this project has led to the fact that urban transport companies have begun to explore the use of clean energy sources in vehicles with increasing frequency. To implement the assumptions of sustainable development in urban transport, including public bus transport, it is very important to ensure a zero-emission vehicle power supply.

Changes in legislation related to the promotion of zero-emission transport are also observed in Poland, where the Polish Act of 16 December 2010 on public collective transport [20] was introduced. This Act, within the scope of its regulation, implements the assumptions of Directive 2009/33/EC of the European Parliament and of the Council of 23 April 2009 on the promotion of clean and energy-efficient road transport vehicles [21]. Due to the fact that in most of the cities in Poland, public transport is based on bus transport, intensive efforts are being made to replace rolling stock with low- and zero-emission vehicles, including hydrogen-powered ones.

There are opinions that hydrogen may soon replace or limit the currently promoted electric drives in transport means. This is related to its main disadvantages, which are the high costs of purchase and subsequent utilisation of this vehicle type [18]. So far, these opinions are related mainly to urban transport [22]. Researchers also emphasise that hydrogen propulsion is more promising, as buses powered by these drives have a greater range than vehicles equipped with lithium-ion batteries [23]. In addition, hydrogen-powered buses do not require a charging network as extensive as in the case of electric vehicles, and the time of hydrogen refuelling operation is much shorter than battery charging [24].

It should be noted that the directions of hydrogen technology development are shaped by the European transport policy. By 2030, the European Commission plans to allocate 65 billion EUR to investments related to hydrogen storage and distribution [25]. These funds are to be primarily used to create a network of hydrogen refuelling stations [26]. The European Commission has issued announcements that present its vision and course of action for the development of hydrogen technology and its application in transport [27]. These announcements indicate that total investments in renewable hydrogen in Europe may reach 180–470 billion EUR by 2050, and investments in low-carbon hydrogen from fossil fuels—from 3 up to 18 billion EUR [25].

Therefore, based on the examples of different countries, e.g., the UK [28], it is necessary to establish a multifaceted plan for the transition from the supply of conventional to alternative fuels to urban buses, and it may be hydrogen. These types of changes result from the EU transport policy and are widely described in the study [29], where current research topics related to public transport, important for regulatory bodies, transport planners, and operators, were analysed, as well as the broader economic context and compared energy consumption in all forms of public transport were emphasised.

However, the usage of hydrogen as a fuel in transport vehicles deals with a number of challenges that may be faced by transport companies implementing these vehicles. Hydrogen supply chains should be developed. Moreover, plants producing green hydrogen should be selected or built. Decisions on shaping supply chains and infrastructural investments are often made considering the demand values for hydrogen that have to be delivered to particular markets.

The mentioned challenges may also impact the decisions made by transport companies that consider the implementation of hydrogen-powered buses. The shape of hydrogen supply chains and regular and cost-efficient access to this fuel may be essential in the decision-making process regarding the purchase of buses used in urban transport. Therefore, the following hypothesis may be formulated: “Access to hydrogen, as well as hydrogen prices, are influencing the decision to purchase hydrogen-powered buses to the greatest extent”.

2.3. Technical and Operational Aspects

Technical and operational aspects should be taken into account to ensure the safe and efficient operation of hydrogen-powered vehicles. This broad issue involves, among other things, the development of specific infrastructure, including, for example, hydrogen storage and refuelling stations and hydrogen production and supply systems.

Currently, the main efforts of scientists seem to be directed at the development of safe, efficient, and low-cost techniques and technologies for the production [30], storage [31], and transport of hydrogen in liquid and gaseous states [32]. Several publications dealing with, among others, the design and optimisation of hydrogen supply chains have been published [33,34]. De-León Almaraz et al. [35] presented a project on such a multifaceted system in Hungary, while Ling-Chin et al. [36] proposed such a system for Great Britain.

There are studies that describe the hydrogen refuelling infrastructure [37,38]. Greene et al. [37] provide an up-to-date overview of the potential challenges facing stakeholders in the design, planning and implementation of hydrogen refuelling infrastructure. In another study [38], an attempt was undertaken to determine the relationship between station size, i.e., station capacity and operational capacity per day, and the price of building a refuelling station. It was stated that developing markets with low demand for hydrogen are particularly demanding, as in such cases, the cost of building a refuelling station significantly affects the cost of hydrogen offered. Therefore, it can be noted that hydrogen refuelling stations have a major impact on the cost of hydrogen for customers.

In the available literature, there are several scientific studies related to modelling the implementation of the entire system of production, storage, transport, and distribution of hydrogen for, among other things, buses powered by this kind of fuel [39,40]. It is necessary to distinguish among the many methods of hydrogen production [41] that lead to obtaining it in the form of green hydrogen [42,43]. Gunawan et al. [39] present the results of techno-economic modelling of a nationwide hydrogen fuel supply chain for major cities in Ireland. In addition, the model was expanded to include renewable hydrogen production (electrolysers using wind- and solar-generated electricity from photovoltaic panels), transportation, and dispensing systems for fuel cell electric buses.

Similar research, albeit on a smaller scale, was conducted by Stecuła et al. [40]. The authors presented a technical and economic analysis in terms of possible investments in hydrogen buses for public transportation in Katowice (Poland). The study includes a range of needed information concerning, for example, the cost of hydrogen production. The article presents a method for selecting hydrogen-powered buses, a selection of bus lines, and, among other things, an analysis of the location of hydrogen refuelling stations. Moreover, it also presents assumptions regarding the possibility of producing hydrogen directly within a refuelling station. Both studies focus on technical and economic issues, but they do not provide a reference point influencing the decision-making process by municipal utilities for the implementation of hydrogen technology.

2.4. Economic Aspects

It should be mentioned that the market for alternative fuel vehicles is still dominated by electric vehicles (regardless of their type). According to data compiled in the Global Hydrogen Review 2022 [44], by the end of 2021, there were 4700 hydrogen-powered buses registered worldwide, 85% of which were in China (and only 154 in Europe) [45]. In the same period of time, over 670,000 eclectic buses were registered worldwide [44].

One of the factors influencing the decision to purchase a hydrogen bus for urban transport involves seeking answers to the question of what the total cost of ownership of such a vehicle will be. Chen et al. [46] carried out a study to assess the total cost of ownership of a hydrogen bus, considering the main component costs, including the cost of acquiring the bus, the expenses of adapting the infrastructure, operating and maintenance costs of the vehicle and the necessary infrastructure. Moreover, the cost of purchasing hydrogen should also be mentioned. Saha et al. [47] presented several methods of producing hydrogen, discussing the financial and environmental performance of grey, blue and green hydrogen.

It should be noted that there is a lack of comprehensive studies focusing on decision-making criteria, including economic aspects, that influence the decision-making related to the purchase of hydrogen-powered buses, taking into account the transport companies’ opinions.

2.5. Ecological and Social Aspects

Hydrogen is considered a fuel with minimal environmental impact compared to fossil fuels [31,48]. It is important to note that air pollution has a significant impact on human lives. It is not just about health issues. It seems necessary to transpose the impact of health aspects into the economy due to, for example, increased health care costs, increased temporary inability to work, or reduced life expectancy. According to the European Environment Agency report [49], overall, 97% of the EU urban population was exposed to levels of fine particulate matter above the values set in the latest guidelines by the World Health Organization in 2021. Moreover, all EU countries reported levels of ozone and nitrogen dioxide above those recommended by the WHO.

Considering the pace of technology development using alternative fuels, it is important to consider the issue related to the public’s preferences for purchasing hydrogen-powered vehicles. Shin et al. [50] compared and analysed consumer preferences related to the selection of electric and hydrogen-powered vehicles in the Korean market in terms of their environmental impact. A detailed comparative analysis of electric- and hydrogen-powered vehicles was also provided [51].

That is why it is important to change the attitudes of the urban population, mainly road transport users, towards moving around the city by public transport. In this case, the use of hydrogen as a fuel may be a factor influencing the choice of the transport method as environmental awareness in society increases [52,53]. However, knowledge about hydrogen, its varieties, and the safety of its use in transport remains insufficient. Current research [54] emphasises that it is much easier for city dwellers to accept the costs associated with the implementation of hydrogen technologies in public transport when they obtain precise information about the potential benefits of hydrogen technologies for the environment and population. The results of similar studies [55] also indicate an insufficient level of knowledge among the public (e.g., Germany) about hydrogen technology. The increase of interest and participation of the community in hydrogen investments, promoting good practices on a large scale, were indicated as solutions to improve public knowledge.

One of the initiatives supporting the development of hydrogen technologies in the EU is the “The Clean Hydrogen Joint Undertaking”, which brings together the European Commission, Hydrogen Europe, and Hydrogen Europe Research in a public-private partnership [56]. The objective of this project is to support research and development related to hydrogen and to present available knowledge to the public.

Another initiative focused on supporting affiliated cities in the broader field of environmental protection (including the fight against global warming) is the C40 group. C40 is a global network of nearly 100 mayors (currently 96—11 June 2024) of cities around the world who are actively working to address the climate crisis using state-of-the-art, innovative approaches to industry, transportation, and environmental protection. From Europe, C40 members include mayors of cities such as Amsterdam, Athens, Berlin, Copenhagen, Milan, Oslo, Paris, and Warsaw [57].

2.6. Decision-Making Issues for Urban Trasport Vehicles Purchase

The implementation of new technologies is a complex process that requires careful decision-making, taking into account many factors that often change over time. The problem of decision-making touches most areas related to human activity, and as a result, the subject literature covers various aspects. These aspects can include, first of all, cost analysis, benefits, risk management, environmental impact, and social consequences of implemented concepts.

The tools used in the decision-making process depend primarily on the complexity of the factors needed to be considered and the availability of data. Decision-making may be based on, among others, statistical methods, which can be divided into high-complexity methods, special methods, general-purpose methods [58,59], mathematical modelling [60,61], methods based on indicators [62], and multicriteria methods [63,64,65].

The available methods are also applicable to decisions on the implementation of new technologies in public transport [66,67,68], including the implementation of public transport vehicles with alternative power sources [69] and hydrogen technologies [53,70,71].

The key criteria when deciding on the purchase of hydrogen buses primarily include the price of the hydrogen bus [72,73]. It was also mentioned that the high costs of vehicle purchase and charging infrastructure are a significant barrier to the implementation of battery-powered and hydrogen fuel cell buses [74].

For example, in the tender procedure for the purchase of hydrogen buses in Poznan (Poland), 72% of the price, 15% of the warranty and service conditions, 10% of the technical and operational characteristics, and 3% of the technical readiness were decisive in offer selection [75]. This example shows the criteria used to assess the offers selected during the tender procedure by one company. However, they do not present the basic criteria used to make decisions by responsible entities located in different cities in Poland on the implementation of hydrogen-powered buses in public transport. Such a decision is taken before the tender procedure. Therefore, the following hypothesis may be formulated: “economic criteria have the greatest impact on the decision to purchase hydrogen-powered buses in the opinion of urban transport companies operating in Poland”.

Another important issue is related to the entity that decides on the purchase of hydrogen-powered buses for public transport. An analysis of the available literature indicated that the public sector plays an important role in decision-making, e.g., in the United Kingdom, Singapore, and Australia, local governments are involved in this process [76]. In addition, in an available report on strategies for joint procurement of fuel cell buses, 90 European cities and regions where the public sector has participated in the purchase of hydrogen buses were mentioned [77]. However, in these studies, the dependencies of entities making decisions on the purchase of hydrogen-powered buses were not analysed in detail.

In Poland, cities where hydrogen buses are already operating on regular lines or on a test basis include Warsaw, Kraków, Konin, Wrocław, and Gdynia. This is still a small number; however, most cities are considering the possibility of buying hydrogen buses in the coming years. This is related to the 2018 Polish Act on electromobility and alternative fuels [78], according to which local governments with at least 50,000 inhabitants will be obliged to have at least 30% of zero-emission or biomethane-powered buses in their fleets from 2028 onwards. Moreover, the Act also indicates certain intermediate stages for this fleet replacement: 10% of the zero-emission fleet should be operated from 2023 and 20%—from 2025.

Although hydrogen technologies and their use in transport are still developing and are the subject of numerous scientific studies and analyses, there are still gaps that require further investigation. Based on the conducted literature review, the following research gaps were identified related to the lack of a comprehensive analysis:

• dependencies of entities making decisions on the purchase of hydrogen-powered buses,
• criteria for making decisions regarding the purchase of hydrogen-powered buses,
• factors the existence of which would affect the decision to purchase these buses,
• concerns and benefits of transport companies resulting from the purchase of hydrogen buses, considering the transport companies’ viewpoint,
• Therefore, the conditions for making decisions regarding the implementation of hydrogen buses in urban transport systems should be analysed in more detail. This justifies the need to conduct research in this area and fill this gap, which will allow us to supplement the existing state of knowledge and support the decision-making process of enterprises considering the purchase of hydrogen-powered buses.

3. Materials and Methods

3.1. Case Study Description

Poland has been selected as a case study for the presented article. This is related to the early phase of hydrogen-powered bus implementation in urban transport, as well as the lack of a developed systemic approach in the decision-making process related to the introduction of these vehicles in urban transport, taking into account national conditions.

In Poland, the development of hydrogen technologies is promoted and is reflected both in the state’s energy policy and transport policy [79]. These activities are regulated by relevant legislation. These include The Polish Hydrogen Strategy to 2030 with a perspective to 2040, the overarching goal of which is to create a Polish branch of the hydrogen economy, as well as its further development to achieve climate neutrality [80]. As part of the hydrogen strategy, it is planned to operate 100–250 hydrogen buses by 2025 and 800–1000 buses by 2030. These plans also provide for the construction of a minimum of 32 hydrogen refuelling stations by 2025. The second important regulation is the National Energy and Climate Plan for 2021–2030 [81], which contains assumptions, objectives, and actions in the implementation of the 5 dimensions of the Energy Union related to emissions reduction, increasing energy efficiency, or broadly understood energy security.

These regulations impose an active action obligation on all local government bodies and entities performing urban transport in cities related to hydrogen technology implementation. Public transport companies are involved in hydrogen-powered vehicles implementation in the country. In Poland, these companies operate in all 16 voivodeships (Figure 1).

Varying numbers of public transport companies existing in the respective regions are observed. This is influenced, among others, by their demographic and spatial structure. It is worth noting that the basic type of urban transport in Poland is buses (12.3 thousand units, representing 78.7% of the total number of public transport vehicles nationwide [83]). According to the data of Statistics Poland, at the end of 2021, the total length of bus lines was 56.9 thousand km [83]. The size of the bus fleets in Poland possessed by companies operating in individual voivodeships at the end of 2021 is presented in Figure 2. According to another study [84], out of the entire bus fleet, 15.4% (1894 units) powered by alternative fuels (mainly electric vehicles) were in operation in the same period.

According to the Polish Act on Electromobility, cities and towns with at least 50,000 inhabitants are obliged to have at least 30% of zero-emission or biomethane-powered buses in their city bus fleets from 2028 onwards [78]. Considering the most important factor forcing the transformation of the bus fleet into a low-emission and emission-free one, which is the population of Polish cities, it can be concluded that the intensity of work on this issue will increase. It is worth noting that at the end of 2021, 90 out of 964 Polish cities and towns had a population of 50,000 or more [85].

3.2. The Way to Conduct the Research

The aim of this research was to analyse the conditions for making decisions regarding the implementation of hydrogen-powered buses (HPB) in urban transport. The research was focused on public transport companies operating buses in Polish cities and towns with more than 50,000 inhabitants.

The methodology applied to conduct the research is presented in Figure 3.

The following 4 research questions were formulated:

• Who decides on the implementation of hydrogen-powered buses?
• What criteria influence the decision to purchase hydrogen-powered buses?
• What factors would influence the decision to purchase hydrogen-powered buses to a greater extent?
• What are the benefits and concerns of implementing hydrogen-powered buses?

The research hypotheses were formulated as follows:

• Economic criteria have the greatest impact on the decision to purchase hydrogen-powered buses, according to the opinion of urban transport companies operating in Poland.
• Access to hydrogen and hydrogen prices are influencing the decision to purchase hydrogen-powered buses to the greatest extent.

After a detailed analysis of the subject literature, the criteria influencing the decision on the purchase of hydrogen-powered buses were identified (

Table 1. Criteria influencing the decision to purchase hydrogen-powered buses by public transport companies [own elaboration].

Criterion	Characteristics
Economic	The cost of buying a bus, Operating cost of the bus, Cost of operator training, The cost of purchasing hydrogen, etc.
Ecological	Reducing the negative impact on the environment, including: emission of gaseous and particulate pollutants, noise, etc.
Organisational and legal	Implementation of legislative requirements, Possibility to adjust the process of servicing vehicles in a transport company, Decision-making and implementation procedures for the investment, Forms of cooperation between interested parties, etc.
Social	Ecological awareness of urban residents, Attitudes of residents towards urban transport, etc.
Technical and operational	Ongoing maintenance and service of hydrogen buses, Access to infrastructure, including hydrogen refuelling stations, vehicle service stations, etc.

).

During the Value_H Seed money project (Interreg SouthBaltic) implementation, meetings were carried out with managers of several urban transport companies operating in West Pomeranian Voivodeship in Poland. Based on the results of consultations and observations of transport companies’ operations in Poland, the factors affecting the decisions related to the implementation of hydrogen-powered vehicles in public transport in Poland were recognised (

Table 2. Factors influencing the decision to purchase hydrogen-powered buses by public transport companies [own elaboration].

Code	Factors
F1	Simplified purchasing decision-making procedures
F2	Simplified formal procedures (including tendering)
F3	Obtaining significant funding for the purchase of the bus (new external sources)
F4	Assistance of external entities (state institutions) in acquiring funds for the purchase
F5	Strengthening cooperation with the research and development sector in the implementation of mobility projects
F6	Introduction of tax benefits
F7	Development of national hydrogen infrastructure
F8	Securing access to hydrogen
F9	Competitive and stable hydrogen price
F10	Popularisation of knowledge regarding the use of hydrogen technologies

).

Moreover, as a result of consultations with representatives of selected urban transport companies, concerns (

Table 3. Concerns about the purchase of hydrogen-powered buses by public transport companies [own elaboration].

Code	Concerns
C1	Limited access to knowledge concerning the use of hydrogen technologies
C2	The need to have trained drivers and service staff
C3	Difficulties in financing the costs of buying buses
C4	Difficulties in financing the operating costs of buses
C5	Difficulties in financing the costs of training drivers and service staff
C6	Limited access to hydrogen
C7	Limited access to charging stations
C8	The need to adapt the technical facilities for the operation of hydrogen buses
C9	Variability in the level and stability of hydrogen prices
C10	Increase in ticket prices
C11	Decrease in the number of passengers
C12	Difficulties in the operation of hydrogen buses
C13	Complex and multi-level decision-making process related to the implementation of hydrogen buses
C14	Complex and lengthy tender procedures related to the purchase of buses
C15	Difficulties in securing external sources of financing

) and benefits (

Table 4. Benefits associated with the purchase of hydrogen-powered buses by public transport companies [own elaboration].

Code	Benefits
B1	Environmental protection (reduction of pollutant/noise emissions)
B2	Improvement of the company’s image and the city’s promotion
B3	Increase in the competitiveness of the enterprise
B4	Business development
B5	Implementation of corporate social responsibility (CSR) assumptions
B6	Meeting the requirement to operate zero-emission buses
B7	Increase in the volume of transport as a result of the residents’ ecological awareness improvement
B8	Innovativeness of rolling stock
B9	Longer range (when compared to electric vehicles)
B10	Shorter charging time (when compared to electric vehicles)
B11	Strengthening of the economic position of the company

) related to the implementation of hydrogen-powered buses were identified.

In order to examine the respondents’ opinions, a questionnaire was developed consisting of two parts. The first part of the questionnaire contained general questions identifying the profiles of the respondents participating in the survey. The second part of the questionnaire included specific questions regarding respondents’ opinions on the investigated issues. The questionnaire included single-choice and multiple-choice questions. For several questions available in the second part of the questionnaire, it was also possible to assess the proposed options using a Likert scale [86] from 1 to 5, where 1—the least important aspect, 5—the most important aspect. This approach allowed the creation of the rankings of the analysed options.

The questionnaire was sent to transport companies providing public transport services in Poland. The questionnaire, in an electronic version, was sent by the Chamber of Commerce for Public Transport [87] to its members. The Chamber associates 122 public transport enterprises operating in Poland, including 5 enterprises involved in tram communication only, which did not take part in the study. The survey was anonymous, and participation was voluntary.

The questionnaire was available for completion online from 27.02.2023 to 15.03.2023. The questionnaire was completed by 46 representatives of transport companies operating bus transport and located in various voivodeships in Poland. These were mainly directors, presidents, and heads of departments in the companies. However, the group of potential respondents was limited to public transport enterprises associated with the Chamber of Commerce for Public Transport, and the surveyed respondents formed a representative group of urban transport companies in Poland.

Subsequently, the results of the survey were analysed. Based on the achieved results analysis, it was possible to:

• determine the decision-makers’ structure,
• elaborate the rankings regarding criteria, concerns, expected benefits and factors influencing the decision to purchase hydrogen-powered buses,
• determine the significance degree of the answers obtained.

Then, a discussion was carried out, and appropriate recommendations and conclusions were drawn.

4. Results

Analysing the answers to the general questions (included in the first part of the questionnaire), it can be concluded that the respondents came from 14 out of 16 voivodships in Poland (Figure 4). Most of the answers came from the Wielkopolskie Voivodeship (six answers), followed by the Pomeranian and Silesian Voivodeships (five answers each). In answering this question, the respondents could mark several options because some of the public transport companies can carry out transport services in different voivodeships at the same time. Nevertheless, no respondent made use of this option, indicating only one voivodeship.

Respondents participating in the research were employed in managerial positions in their workplaces (Figure 5). Among the positions held, most respondents selected the “Director/President/Deputy director” option (82.6% of respondents) followed by “head of the technical department” (8.7% of respondents). Among the remaining options, the respondents indicated employment as a head of the sales/marketing department and specialist in the organisation of transport development and marketing (2.2% each). Of the respondents, 4.3% did not indicate their positions.

The seniority of the practitioners in the given position in 50% of the answers exceeded 15 years, and the option “less than 5 years” was selected by 23.9% of the respondents, which may have been associated with a promotion in previous years. 19.6% of the answers came from people with 5–10 years of seniority, while only 6.5% of the respondents selected the 11–15 years option.

Respondents indicated the area served by public transport by their companies, while they could select several proposed options (Figure 6). It should be noted that 97.8% of the representatives of transport companies indicated that the activities of the represented enterprises cover urban areas, and 78.3% also serve suburban areas (e.g., neighbouring municipalities). In turn, intercity transport within the borders of an agglomeration was indicated by nine representatives of the surveyed enterprises (17.4% of respondents selected this option).

In the second part of the questionnaire, respondents were asked to answer questions about the possibility of implementing hydrogen-powered buses. When asked whether the company was considering expanding its fleet structure with hydrogen-powered buses, 43.5% of the responses were negative (Figure 7). This may be associated with great fears of changing the rolling stock structure to a hydrogen-powered one. A positive answer was indicated by the same number, i.e., 43.5%, of respondents. This demonstrates that these people see the potential and opportunity to enrich their vehicle fleet with hydrogen buses. On the other hand, 12.8% of respondents marked the option “it is difficult to say”, which may be related to the lack of a developed position on this issue.

Respondents were also asked who ultimately makes the decision to implement innovative solutions in public transport (Figure 8). This question was a multiple-choice one. The vast majority of respondents (97.8%) indicated that city or town authorities ultimately make this decision. The director of a transport company may also be involved in the decision-making process (this option was selected by 54.3% of the respondents). In 19.6% of the analysed answers, the option “supervisory board of the company” was selected. Among other entities, the respondents indicated the company’s management board (two responses). Answering the first research question, it can, therefore, be concluded that the decision-making process related to the implementation of hydrogen-powered buses in public transport companies is complex. These decisions can be shared, but in Poland, the city or town authorities have the largest impact on the decision-making process.

In turn, when asked who was responsible for the course of the tender procedure for the purchase of buses (Figure 8), the respondents could also select several options. Most answers indicate the director of the transport company (69.6%), followed by the city authorities (58.7%). The least responses were given to the company’s management board and supervisory board. This confirms the fact that decisions regarding the purchase of new rolling stock are shared, which affects the course of the implementation procedure.

In order to obtain an answer to the second research question, the impact of the identified criteria on the decision regarding the purchase of hydrogen-powered buses was examined (Figure 9). Respondents were asked to mark their answers on a Likert scale from 1 to 5, where 1—the smallest impact and 5—the largest impact.

Analysing the data presented in Figure 9, it can be concluded that the economic criteria have the greatest impact on the decision regarding the purchase of hydrogen-powered buses (the arithmetic mean of the ratings was 4.63). This may be related, among others, to the high costs of purchasing and operating hydrogen-powered vehicles. In addition, representatives of transport companies also rated the technical and operational criteria high (with an arithmetic mean of the ratings of 4.22), which may be related, among others, to the need to provide services for these vehicles at the company’s headquarters. Ecological criteria also have a large impact on the decision related to the purchase of hydrogen-powered buses (the arithmetic mean was 4.10). This is related, among others, to the fact that according to the Electromobility Act [78], by 2028, 30% of the urban rolling stock operating in Poland must be zero-emission. It should be noted that the organisational, legal, and social criteria were assessed as relatively low (average scores of 3.16 and 3.14, respectively), which indicates that, according to the respondents, these criteria have a relatively small impact on the decisions made concerning the purchase of vehicles.

Then, the respondents were asked to assess their concerns related to the implementation of hydrogen-powered buses using a Likert scale from 1 to 5, where 1 is the lowest significance level, and 5 is the highest significance level. When analysing the obtained answers, they were grouped considering the degree of significance (S), where individual degrees were marked in colours. It was assumed that red indicates a very high level of significance (ratings on a scale of 4.5 and above), orange—high (3.5–4.49), yellow—medium (2.5–3.49), green—low (1.5–2.49), and blue—very low (below 1.49). An analogous evaluation system was applied when analysing subsequent answers to questions.

Among the biggest concerns (Figure 10), representatives of transport companies mentioned the limited access to refuelling stations (arithmetic mean of 4.49), limited access to hydrogen (4.44), and difficulties in financing the operating costs of buses (4.43). The least significant concerns were related to difficulties in financing the costs of training drivers and service staff (2.48) and the decrease in the number of passengers (2.21). The analysis of the responses proves that the biggest concerns are related to technical (including infrastructure), organisational, and economic issues. It should be noted that the results of the significance analysis do not reach extreme values (none of the answers were classified under red and blue).

Representatives of transport companies also expressed their opinions on the benefits they would expect from the implementation of hydrogen-powered buses. These benefits were also assessed on a Likert scale from 1 to 5, where 1 is the lowest significance level, and 5 is the highest significance level. When assessing the benefits, the respondents rated environmental protection as significant (reduction of pollutant/noise emissions), with an arithmetic mean of ratings of 4.43 (Figure 11). Among the important aspects, a longer vehicle range (4.19) and the improvement of the company’s image and city promotion (4.17) were also noted. The least important aspect would be the increase in the volume of transport as a result of improving residents’ ecological awareness (mean rating—3.0). The analysis of the answers proves that the greatest benefits are perceived in environmental aspects, which may be related to the applicable legal regulations in the country. The range of assessments is in a narrow range (arithmetic means are from 4.43 to 3), and the answers cover only two levels of significance (orange and yellow).

Subsequently, the respondents were asked to comment on the factors that would affect their decision to purchase hydrogen-powered buses. Similarly to the above questions, respondents were asked to assess individual factors by applying the Likert scale from 1 to 5, where 1—the smallest impact and 5—the largest impact (Figure 12).

Analysing the data given in Figure 12, it should be stated that providing access to hydrogen is perceived as the most important in the context of the decision by transport companies in Poland to purchase hydrogen-powered buses (the arithmetic mean of the ratings was 4.86). The competitive and stable price of hydrogen (4.81) was also ranked high. Respondents also indicated the difficulties related to covering the costs of purchasing buses (4.76); therefore, obtaining significant funding for the purchase of buses would be necessary. Transport companies’ representatives saw the smallest problem in the procedural proceedings related to the purchase of buses (with a mean value of 2.73) and formal procedures (2.71). Analysing the answers to the question, it can be seen that the respondents rated economic, technical (including infrastructure), and organisational issues very high. It is worth noting that half of the factors assessed are at a very high level of significance. It can, therefore, be concluded that these factors are prerequisites for the decision to purchase hydrogen-powered buses to be positive.

Based on the analysis of the obtained ratings of significance S, it is possible to identify the most important aspects that should be considered when deciding whether to include them in the further detailed investigation (

Table 5. Exemplary ranges of analysed aspects’ significance [own elaboration].

Range	Colour	Degree of Significance	The Degree of Significance Acceptance	Decision
$4.5\le S\le 5$	Red	Very high	Highly acceptable	It is highly recommended to consider this aspect in further analysis
$3.5\le S\le 4.49$	Orange	High	Acceptable	It is recommended to consider this aspect in further analysis
$2.5\le S\le 3.49$	Yellow	Medium	Conditionally acceptable	The aspect may be considered under specific conditions
$1.5\le S\le 2.49$	Green	Low	Unacceptable	It is not recommended to consider this aspect in further analysis
$1\le S\le 1.49$	Blue	Very low	Highly unacceptable	The aspect may be excluded from further analysis

).

The presented degrees of significance may be applied for the analysis of concerns, benefits, and factors impacting the decision to purchase hydrogen-powered buses.

5. Discussion

Considering the challenges faced by entities involved in the implementation of hydrogen-powered buses in urban transport, it is important to search for solutions that facilitate decision-making processes.

The analysis of the research results allowed us to answer the research questions and fill in the gaps. The following answers were achieved:

• dependencies of the entities making decisions regarding the purchase of hydrogen-powered buses. It was stated that the city or town authority mainly makes the decision to implement innovative solutions in public transport in Poland; however, the tender process for the bus purchase is more often organised by the director of the transport company. It should be noted that different dependencies could take place. Therefore, it is recommended that city or town authorities intensify efforts to seek funding for the purchase of hydrogen-powered buses, which confirms the importance of the economic aspects influencing decision-making in this field. In turn, directors of transport companies should concentrate their efforts on the decision-making process related to defining the parameters of the transport means and the tender organisation (concentrating mainly on technical and operational aspects).
• criteria for making decisions regarding the purchase of hydrogen-powered buses. It was stated that economic criteria are considered the most significant among other criteria in the opinion of urban transport companies’ representatives in Poland. This proves the results of other studies highlighting that the major obstacle for fuel cell buses is high investment costs [72] and that the usage of hydrogen-powered buses is about 25–30% more expensive than electric buses [73]. Therefore, carrying out economic analysis based on the prognosis of future costs of bus purchase and operation (considering possible market changes) will be needed for future efficient decision-making.
• factors, the existence of which would affect the decision to purchase these buses. Surveyed transport companies’ representatives gave the high rates to five factors, including securing access to hydrogen, competitive and stable price of hydrogen, obtaining funding for bus purchase, development of national hydrogen infrastructure, and assistance of external entities in acquiring funds for purchases. These factors correspond to economic, technical, and operational aspects. Therefore, hydrogen supply chain development, including storage facilities and refuelling stations, is expected by potential hydrogen users, which is in line with environmentally friendly, cost-effective, and socially acceptable policy implementation [89]. Therefore, the intensification of infrastructure development and the design of cost-efficient hydrogen supply chains in Poland will reduce investment concerns related to bus purchases.
• concerns of transport companies resulting from the purchase of hydrogen buses. Among the examined concerns, respondents paid the most attention to limited access to charging stations and hydrogen. This result also confirmed that transport companies’ representatives are mostly worried about hydrogen-powered bus operations, which deal with technical and operational aspects and are related to the need for hydrogen supply chain development.
• benefits to transport companies, resulting from the purchase of hydrogen buses. In the opinion of the surveyed respondents, the environmental protection benefit received the highest rates, which shows the awareness of transport companies’ representatives to respect the principles of sustainable development of transport [19,21].

A practical consequence of the concerns identified in the study, such as limited availability of hydrogen, charging stations, or problems with financing the purchase and subsequent operation of hydrogen buses, could be the reluctance of decision-makers to implement such solutions. Therefore, it is important to develop recommendations on how to address the identified challenges. These recommendations should be addressed to both transport companies and city authorities. City authorities should become involved in the development of hydrogen infrastructure (hydrogen production facilities, charging stations, etc.) by creating incentives for investors, e.g., by making land available at preferential prices or by creating special economic zones.

It is also crucial to obtain funding for the purchase and subsequent maintenance of hydrogen buses. Financial support can be obtained from international and national programmes, such as the Polish Green Public Transport programme implemented by the National Fund for Environmental Protection and Water Management [90]. Furthermore, the financial and non-financial benefits of the analysed technology should be considered as a motivating factor for the implementation of hydrogen buses.

Bearing in mind that the mission of public transport, among other things, is to improve the living conditions of residents, the benefits of reduced air pollution and lower noise levels are very important. From the viewpoint of transport companies, it is also essential to develop the company and improve its image.

Therefore, based on the collected opinions, actions were proposed that may support the decision-making process regarding the implementation of hydrogen-powered buses in public transport.

General recommendations to improve the decision-making process for the implementation of hydrogen buses in public transport in an individual country/city include the following:

• Identification of national conditions for the operation of public transport.
• Identification of decision-making dependencies between urban transport stakeholders.
• Identification and analysis of possible hydrogen supply chains, including available and planned infrastructure elements and hydrogen pricing.
• Identification of manufacturers/suppliers of buses and estimation of expected purchase prices of buses.
• Identification of bus service capabilities at the use points.
• Carrying out a cost-effectiveness analysis and determining possible funding sources.
• Establishing specific conditions and decision-making criteria specific to the individual country/city.
• Conducting an analysis of specific conditions and criteria relevant to an individual country/city.

Specific recommendations were also proposed and addressed to transport companies and city authorities (

Table 6. Recommendations to support the decision-making process for the deployment of hydrogen-powered buses in public transport [own elaboration].

Decision-Making Criteria	Recommendations for Transport Companies	Recommendations for City Authorities
Economic	searching for external sources of co-financing for investments (e.g., national or international programmes); creation of financial reserves for investments; estimation of the costs of purchase and operation of buses; analysis of short- and long-term benefits;	active search for programmes co-financing investments in the purchase of hydrogen-powered vehicles; financial support for transport companies; creation of tax credits, subsidies and other forms of support;
Technical and operational	provision and/or adaptation of the infrastructure and appropriate workshop equipment for servicing vehicles; providing permanent service for hydrogen vehicles (e.g., internal or external service facility); ensuring ongoing vehicle inspections and diagnostics;	provision and maintenance of infrastructure for supplying buses with hydrogen and their servicing;
Ecological	fulfilling the assumptions of legal acts in terms of the required number of zero-emission vehicles; care for keeping the rolling stock in proper technical condition.	meeting the requirements for the number of low-emission vehicles in accordance with the Electromobility Act;
Organisational and legal	searching for and selecting a hydrogen supplier to ensure uninterrupted and stable supply of hydrogen; defining the rules of close cooperation between the company’s technical department and the supplier/service of the device/hydrogen supplier; defining the rules of cooperation between the transport company and the city authorities; development and implementation of safety procedures for the operation of hydrogen vehicles; establishing cooperation with scientific and research institutions; training of employees involved in bus operation;	defining the rules of close cooperation between the city authorities and transport companies; supporting hydrogen production and supply processes; defining the rules of cooperation with entities responsible for obtaining external funds for the purchase of zero-emission rolling stock; facilitating tender procedures; modification of the city’s development strategy towards the use of hydrogen vehicles; development of the concept of using hydrogen buses to operate lines in city centres or other urbanised districts; establishing cooperation with scientific and research institutions;
Social	promotion of ecological solutions; development and implementation of responsible business strategies; participation in fairs and events in the field of hydrogen technologies.	conducting a social campaign to raise awareness of the use of hydrogen vehicles; organisation of educational events raising the level of environmental awareness of residents; ticket incentives and promotions.

).

Moreover, it is very important to establish and ensure cooperation between the various entities involved in making decisions related to the implementation of hydrogen-powered vehicles.

6. Conclusions

This article analyses the conditions for making decisions regarding the implementation of hydrogen-powered buses in public transport. The case study was examined, and the opinions of representatives of transport companies operating in Poland were analysed on aspects affecting decisions related to the implementation of hydrogen-powered buses. The results of the conducted research broaden the current knowledge related to the conditions for deciding on the implementation of hydrogen-powered buses.

Representatives of the surveyed companies expressed an opinion on the possibility of enriching their fleet structures with hydrogen-powered buses, and 43.5% of the respondents were negative in this regard. This could have been related to concerns and difficulties related to the implementation of these vehicles. The biggest concerns expressed by transport companies’ representatives are related to limited access to refuelling stations and limited access to hydrogen, as well as difficulties in financing the operating costs of buses.

Interestingly, the same number of responses expressed their desire to enrich the fleet structure with hydrogen-powered buses. This, in turn, may result from the perception of hydrogen technologies as future-oriented and promising. The most important benefits include environmental protection, a greater range of vehicles in comparison to electric buses, and improvement of the company’s image.

Surveyed representatives of urban transport companies highly assessed the economic criteria’s impact on the decision to purchase hydrogen-powered buses. This result proved the first research hypothesis that economic criteria have the greatest impact on this decision, according to the opinion of representatives of transport companies operating in Poland. This also corresponds to the results of previous individual case analyses, where attention was paid to the high costs of vehicle purchases [72,73,74].

According to the surveyed respondents, there are numerous factors that could facilitate their decision to implement hydrogen-powered buses. The most important ones include, among others, providing access to hydrogen, competitive and stable prices of hydrogen, obtaining significant funding for the purchase of buses, development of hydrogen infrastructure, and assistance of external entities in obtaining funds for the purchase of buses. Importantly, these factors were very highly rated among the respondents and must occur simultaneously.

It has to be highlighted, however, that the main problem determining the consideration of hydrogen bus implementation in public transport is access to hydrogen at an acceptable price. This result proves the second research hypothesis that access to hydrogen, as well as hydrogen prices are influencing the decision to purchase hydrogen-powered buses to the greatest extent. Nevertheless, it should be noted that in order to meet the requirements of sustainable transport development, access to green hydrogen should be ensured. To this end, it is important to support not only municipal but also national authorities in establishing supply networks and access to green hydrogen refuelling stations. Appropriate targeting of legislation, strategies, and policies for the development of sustainable transport in the country will be of significance in this regard.

The research results demonstrate that the decision-making process regarding the implementation of hydrogen-powered buses in public transport companies in Poland is complex. These decisions are shared mainly between city authorities and transport companies. This also applies to the tender process. However, in the decision-making process in Poland, city authorities play a key role: they remain legally responsible for public transport.

Based on the results of this research, joint recommendations for transport companies and city authorities were proposed. These include, among others, establishing close cooperation between various entities involved in making decisions related to the implementation of hydrogen-powered vehicles.

Recommendations addressed to transport companies include the following:

• active search for sources of financing for the purchase and operation of hydrogen buses.
• searching for and selecting a hydrogen supplier to ensure an uninterrupted and stable supply.
• adapting the company’s infrastructure (e.g., operating base) and processes to operate these vehicles (e.g., training and safety procedures), etc.

On the other hand, the most important recommended actions for city authorities include, among others:

• supporting transport companies in their efforts to purchase hydrogen-powered buses and active participation in decision-making processes,
• financial support for transport companies and/or active search for external sources of financing for the purchase of hydrogen-powered vehicles,
• provision and maintenance of infrastructure for supplying buses with hydrogen and their servicing, etc.

It is worth noting that some factors are independent of the activities of transport companies and city authorities, as they are conditioned by the market; this applies, for example, to hydrogen prices. In this respect, however, it can be proposed that state authorities consider various regulation forms for hydrogen prices.

It should be mentioned that the results of the study were largely influenced by the time it was carried out. At the beginning of 2023, when the study was carried out, many cities in Poland began to consider the purchase of hydrogen-powered buses; however, due to the lack of a systemic approach in the decision-making process, they encountered difficulties that generated several fears. The main limitation of the research was access to bus companies that were willing to fill out the questionnaire survey. Moreover, the research results are limited to the conditions of companies operating in Poland. Therefore, it would be reasonable to repeat the research and investigate the conditions of hydrogen-powered bus implementation in other regions of Central and Eastern Europe.

The results of the conducted research may be of help to transport companies and city authorities considering the implementation of these vehicles. Nevertheless, with the spread of hydrogen technology to verify the positions of decision-makers, research should be repeated in the future. It should be noted that the methodology applied to conduct the research may be used by decision-makers located in different countries/cities to examine the individual conditions impacting the decision-making process.

The direction of the authors’ future research will focus on further analyses of the aspects affecting the implementation and operation of hydrogen-powered vehicles. Moreover, a decision-making model facilitating the implementation of hydrogen-powered buses in public transport is planned to be developed.