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Review

Challenges and Solutions of Hydrogen Fuel Cells in Transportation Systems: A Review and Prospects

by
Omar Fakhreddine
*,
Yousef Gharbia
,
Javad Farrokhi Derakhshandeh
and
A. M. Amer
College of Engineering and Technology, American University of the Middle East, Egaila 54200, Kuwait
*
Author to whom correspondence should be addressed.
World Electr. Veh. J. 2023, 14(6), 156; https://doi.org/10.3390/wevj14060156
Submission received: 16 May 2023 / Revised: 1 June 2023 / Accepted: 7 June 2023 / Published: 13 June 2023
(This article belongs to the Topic Transportation in Sustainable Energy Systems)
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Abstract

Conventional transportation systems are facing many challenges related to reducing fuel consumption, noise, and pollutants to satisfy rising environmental and economic criteria. These requirements have prompted many researchers and manufacturers in the transportation sector to look for cleaner, more efficient, and more sustainable alternatives. Powertrains based on fuel cell systems could partially or completely replace their conventional counterparts used in all modes of transport, starting from small ones, such as scooters, to large mechanisms such as commercial airplanes. Since hydrogen fuel cells (HFCs) emit only water and heat as byproducts and have higher energy conversion efficiency in comparison with other conventional systems, it has become tempting for many scholars to explore their potential for resolving the environmental and economic concerns associated with the transportation sector. This paper thoroughly reviews the principles and applications of fuel cell systems for the main transportation schemes, including scooters, bicycles, motorcycles, cars, buses, trains, and aerial vehicles. The review showed that fuel cells would soon become the powertrain of choice for most modes of transportation. For commercial long-rage airplanes, however, employing fuel cells will be limited due to the replacement of the axillary power unit (APU) in the foreseeable future. Using fuel cells to propel such large airplanes would necessitate redesigning the airplane structure to accommodate the required hydrogen tanks, which could take a bit more time.

1. Introduction

Hydrogen fuel cells (HFCs) are electrical cells that can be continuously fed by fuel. The main products of HFCs are electricity and water once a chemical reaction occurs; as a result, clean energy is generated without any noise and air pollution. With the increasing concern about global warming, it appears to be a natural development that the fuel of the future will be entirely hydrogen [1]. Since fuel cells and batteries are based on the premise that in a chemical reaction, the energy is changed into electricity by electron transfer between the anode and the cathode, they have many characteristics in common. In order to produce low DC voltage, not only fuel cells but also batteries require an external load to carry out useful work. In addition to proton exchange membrane and alkaline fuel cells, phosphoric acid, solid oxide, and molten carbonate fuel cells can be considered the most prevalent forms of fuel cells [2].
Fuel cell electric vehicles (FCEVs) offer advantages over battery electric vehicles (BEVs) such as extended range, short refilling times, and lower carbon footprints in manufacturing. FCEVs filter air and can help clean polluted cities, while also being silent and comfortable [3]. However, FCEVs are currently more expensive to produce and have fewer hydrogen refueling stations available [4]. For trucks, FCEVs have the advantage of a lighter weight, allowing for greater payload [5]. FCEVs outperform BEVs for vehicle ranges over 160 km, with advantages including lower mass and volume, faster refueling, initial greenhouse gas reductions, higher well-to-wheel energy efficiency, and potentially lower life cycle costs [6].
In the context of hydrogen fuel cells in the transportation sector, maintenance considerations related to poisoning due to carbon monoxide (CO) or sulfur, as well as associated costs, are crucial. CO poisoning can occur when CO impurities enter the fuel cell, hindering its performance. To mitigate this, purification techniques and catalysts with higher CO tolerance are employed [7]. Sulfur compounds present in fuels can also cause poisoning, degrading the catalysts. Desulfurization processes and sulfur-tolerant catalysts help address this issue [8]. Regarding costs, initial expenses have decreased due to manufacturing advancements, and efforts to improve durability help reduce maintenance costs. Operational and maintenance costs are generally lower compared to internal combustion engines but should still be considered. Overall, regular maintenance, purification methods, and cost optimization contribute to the viability of hydrogen fuel cells in transportation [9].
Hydrogen fuel cell vehicles utilize electric motors for propulsion, with the specific type of motor varying depending on the vehicle’s design and requirements. Two common types of electric motors used in these vehicles are permanent magnet synchronous motors (PMSMs) and induction motors (IMs). PMSMs utilize permanent magnets embedded in the rotor to generate a magnetic field, offering high power density and efficiency. On the other hand, IMs operate through electromagnetic induction and are known for their robustness and cost-effectiveness. Both motor types convert the electrical energy produced by the fuel cell into mechanical power for vehicle propulsion, with the choice between them depending on factors such as power requirements, torque characteristics, efficiency, and cost-effectiveness [10].
In hydrogen fuel cell vehicles, a dualism exists between the slow and constant energy generation of the fuel cell system and the dynamic power demands of road riding, which require high power and rapid acceleration. The fuel cell system generates electricity steadily but may not provide instantaneous power during acceleration. To overcome this, fuel cell vehicles incorporate energy storage systems such as batteries or supercapacitors. These systems store energy to complement the fuel cell’s steady output and deliver the extra power required for rapid acceleration. This dualistic approach ensures a balance between constant energy generation and the ability to meet dynamic power needs, allowing for efficient performance in different driving conditions [11].
The aim of the work is to investigate the practical implementation of hydrogen fuel cells (HFCs) across a diverse range of transportation modes from smallest to largest. Specifically, it focuses on examining the utilization of HFCs in motorcycles, scooters, bicycles, passenger cars, buses, trains, trucks, and aerial transportation systems. Each section provides a comprehensive exploration of the unique challenges, corresponding solutions, and potential advantages associated with integrating HFC technology into these specific modes of transportation. By offering an in-depth analysis of a wide spectrum of vehicles and transportation systems, this paper aims to provide a holistic perspective on the current advancements and future prospects of HFCs in achieving sustainable and efficient transportation.

2. Motorcycles, Scooters, and Bicycles

With the increase in traffic jams in major cities around the world, commuting via motorcycles, scooters, and bicycles has become very attractive for many. The manufacturers of these products are competing to make them even more attractive by making them more efficient and more comfortable. Pearl Hydrogen Power Source Technology Co of Shanghai, China, as a pioneer of two-wheeled vehicles powered by hydrogen, demonstrated the first hydrogen bicycle in 2007. Two-wheeled vehicles (TWV), such as bicycles and motorcycles, are common in transportation systems in many places and countries, notably in Asia, with numerous populations. Consequently, HFC two-wheeled vehicles can help meet air quality standards. In addition, they can affect noise pollution reduction [12].
The development of HFC motorcycles is still immature. Many HFC motorcycle and scooter concepts have been proposed [13,14,15,16,17], and many companies have attempted to construct various technologies and motorbike sizes employing a variety of fuel supplies, including HFCs [18]. Compared to gasoline-powered motorcycles, HFC motorcycles are relatively quiet and highly energy-efficient, with zero emissions. The benefits of HFC motorcycles, then, have the potential to minimize the problems associated with a gasoline-powered system and motivate users to acquire and use HFC motorcycle products [19].
The performance and development of electric motorcycles in Singapore and Malaysia were reported by Weigl et al. [14]. The scholars designed, manufactured, and examined an electrical motorcycle sample that used a combination of an HFC system, a lithium polymer battery pack, and an ultra-capacitor module. The interesting results revealed that the motorcycle can travel approximately 2400 km on hilly roads at 77 (km/h), even during heavy rain. The fuel consumption of the sample was 0.51 kg H2 per 100 km. The results guaranteed that the motorcycle could be built and used for actual road applications [14,20]. Compared to low-carbon transportation systems powered by fossil fuels, HFC sources stand out due to the high-efficiency electrochemical reactions in HFC batteries [21]. The employment of HFCs for evaluating the environmental sustainability of urban delivery systems was applied to different hydrogen vehicles in Italy by Bartolozzi et al. [22]. It was reported that transportation systems powered by HFCs provide a maximum efficiency of 63%, which is much higher than that of conventional fuel consumer engines in Italy.

3. Passenger Cars

In recent years, HFC automobiles have drawn interest as a potential replacement for conventional gasoline-powered systems. Instead of burning gasoline, which produces merely water vapor as a byproduct, HFC automobiles generate energy through a chemical reaction, which occurs between H2 and O2. According to an International Energy Agency (IEA) report, fuel cell vehicles (FCVs) could potentially reach 10–15% of all passenger cars, trucks, and buses by 2050, leading to a 19% decline in universal energy-related CO2 emissions [23]. By the beginning of 2021, there were over 34,000 FCVs on the road globally [24], with the majority in Japan, California, and Germany. While there are still hurdles to overcome in terms of infrastructure and cost, the growing interest in hydrogen fuel cell cars has spurred innovation and investment and provides not only cleaner but also more sustainable transportation for the future than conventional systems.
Despite the efforts made by the automotive industry in the past few years to decrease the effects of ICEs on the environment, they have still not been able to bring emissions to an acceptable level. Burning fossil fuels, such as diesel, in internal combustion engines (ICEs) creates toxic byproducts such as NOX, CO, and CO2, which are very detrimental to the environment. In 2020, passenger cars were responsible for 41% of the 7.3 billion metric tons of carbon dioxide in global transportation emissions [25]. Therefore, and for the sake of a cleaner and more sustainable environment, the transition to electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) has become inevitable [26]. The early attempts to introduce EVs in the 1990s were not successful because of their costs and low performance in terms of top speed and travel range in comparison with vehicles run on ICEs. With recent advancements in battery and fuel cell technologies, many automotive manufacturers have announced plans to begin serious production within the next two to three years. EV sales will exceed 10% of global vehicle sales in 2022 and are expected to reach 30% by 2030 [27]. Concurrently, the global market share of fuel cell technology is expanding rapidly. In 2022, the fuel cell revenue was estimated at USD 2.9 billion with a projected increase to USD 9.1 billion by 2027 [28]. The combination of EVs with fuel cell technology is predicted to revolutionize the automotive industry soon.
High power density, the capacity to respond to significant swings in power demand, and employing a low-temperature solid electrolyte providing hydrogen ions are the most essential aspects in selecting the finest fuel cells for passenger cars. For this reason, automobile manufacturers choose to equip new cars with proton exchange membrane (PEM) fuel cells. Due to its abundant availability and strong reactivity, oxygen is used in PEM fuel cells as the oxidant and hydrogen (H+) as the electrolyte [29]. PEM can function at temperatures between 70 °C and 90 °C while maintaining a pressure of 1 to 2 bars. The PEM fuel cell has several benefits in addition to its low operating temperatures, such as being a dry, solid, and non-corrosive electrolyte; tolerance to carbon dioxide content in the surrounding air; high current and voltage; high density of power; and small size and simple design [30]. The energy content of hydrogen is 120 MJ/kg, more than double that of liquefied natural gas, diesel, and gasoline [31].
Though hydrogen fuel cells can offer numerous benefits to vehicles, they have certain drawbacks. These drawbacks include a lengthy startup period, a lack of power output at slower speeds, a delayed response when a quick surge in power is required, and excessive power output during rapid acceleration [32]. These drawbacks can be avoided by integrating a secondary energy storage system that would function in tandem with a fuel cell. If the fuel cell is unable to generate enough energy on its own, this hybrid setup can provide the necessary power. Two groups of these hybridized systems may be distinguished: fuel cell electric vehicles (FCEVs) and fuel cell plug-in hybrid electric vehicles with a longer range (FC-PHEVs).
Similar to a battery electric vehicle (BEV), an FC-PHEV engine with internal combustion burns gasoline and can be used for powering the vehicle when the battery is near depletion, during acceleration, or when intensive heating and cooling loads exist. FC-PHEV increases driving range while cutting down on fuel expenses and hazardous pollutants. FCEVs, on the other hand, rely on the hydrogen that has been stored in tanks to turn chemical energy into electrical energy. FCEV batteries are charged by electricity generated by onboard hydrogen fuel cells or by a regenerative braking technology, which converts kinetic energy gained during braking into electrical power.
The powertrain of an FCEV consists of a number of hydrogen containers, as shown in Figure 1. Fuel cell stacks, a power converter, a rechargeable electric battery used to store energy, and a power distribution unit make up the FCEV configuration. The power needed to drive the vehicle comes from the HFC, which converts the hydrogen energy into electricity and saves it in the battery. The battery charges by the regenerative braking system during barking. The fuel cell does not need to provide any power when the vehicle is in the regenerative braking phase. A power distributor unit (PDU) is used to regulate this shift in power consumption.
Dr. Roger Billings developed the first ever hydrogen-powered fuel cell car in 1991 once he adopted a battery-powered Ford Fiesta model [31]. Later in 1994, Daimler-Benz released the NeCar I (output of 30 kW and a maximum range of 130 km), the first fuel cell-powered car suitable for everyday usage. This was the spark that ignited global innovation in the vehicle fuel cell sector. Due to technological advancement and continual improvement, NeCar II and NeCar III were later introduced with increased storage capacity and driving range (250 km and 400 km, respectively). Among the several fuel cell options, Daimler-Benz chose the PEM fuel cell because it runs at a low temperature of 80 °C and has substantially lower corrosion rates than other fuel cells. The NeCar II was intended to achieve an efficiency of 40–45% by 2003, which is larger than the best diesel automobile engine with an efficiency of 26%. Fuel cells may lower emissions by 90% compared to typical vehicles [33]. Soon after, almost all automobile manufacturers began developing or had concepts for HFC vehicles [31].
General Motors has continuously been a forerunner in the development of electric cars. In 2007, more than 100 HydroGen4 automobiles were built and tested in countries such as Germany and the United States. The automobile could store 4.2 kg of hydrogen, giving it a driving range of 320 km [34]. According to the Society of Automotive Engineers (SAE) J2601 and SAE J2799, once the tanks are empty, they can be replenished in three minutes.
During the 1990s, Honda began the development of HFC vehicles. In 1999, the Honda FCX-V1 was revealed. It was an experimental two-seater vehicle with metal hydride tanks used for storage. FCX-V2 was later developed and included a methanol reformer as well as fuel cell stacks developed by Honda. Using their previous expertise, Honda then developed the FCX-V3. This vehicle stored 250 MPa hydrogen tanks and had a 10 kW power improvement compared to its predecessors.
In 2001, Honda unveiled the FCX-V4. This evolved vehicle had further improvements in terms of storage space as well as a more compact HFC stack. The driving range was further increased to 315 km due to the increase in storage tank pressure to 350 MPa [35]. Figure 2 shows the progress of Honda’s HFC vehicles and their corresponding power output.
Table 1 compares the key parameters of the hydrogen fuel cell-powered automobiles that are commercially available on the market. The designs of several cars, including the Honda FCX Clarity, the Hyundai ix35 (a modified version of the existing Hyundai Tucson), the Toyota Mira I, the Honda Clarity FCEV, the Hyundai Nexo, the Mercedes Benz B-class FCEV, the Chevrolet Equinox Fuel Cell, and the Toyota Mirai II, are shown in Figure 3. All listed vehicles are considered midsized automobiles with almost identical attributes and power outputs. It should be noted that none of the vehicles listed are PHEVs because their battery capacities are less than 2 kWh.

Hydrogen Storage System in Passenger Cars

According to the International Energy Agency (IEA), the United States and China had the most fuel cell vehicles on the road in 2019—around 8000 and 6000, respectively. Japan had just 3600 hydrogen cars on the road in 2019, but the country intends to increase that number to over 811,000 by 2030. Onboard hydrogen storage is one of the most challenging problems in implementing hydrogen fuel cells in automobiles [40]. However, hydrogen has the highest efficiency and the lowest energy density as a fuel. This indicates that hydrogen has the highest energy density per kilogram. This property can be regarded as a benefit for hydrogen fuel, but it might cause some issues when storing it onboard. One solution to this challenge is storing hydrogen as a compressed gas at extremely high pressures.
Smith and Aceves [41] analyzed various techniques for hydrogen storage and how each option affected total weight and, consequently, the driving range of the HEV. Typically, hydrogen has the capability to be stored through methods such as pressurization as a gas, cooling to cryogenic temperatures as a liquid, or in the form of solid fuel through a physical or chemical amalgamation involving substances such as metal hydride [42]. The weight, capacity, efficiency, storage safety, and total cost should all be considered when considering hydrogen tank storage. Chalk et al. [43] propose a simplified schematic of the hydrogen storage system, divided into three segments based on the applied pressure levels, driven by a relatively low-power electrical DC motor, as shown in Figure 4.

4. Buses

With the objective of diminishing greenhouse gas emissions and enhancing air quality in densely populated urban regions, developed nations have made substantial financial commitments toward the advancement of cutting-edge technologies. Public transportation has recently received significant attention due to its huge environmental impact and tremendous opportunity for improvement. Fuel cell buses are an excellent choice for urban public transit, offering significant environmental and economic benefits compared to conventional buses, such as zero emissions, quiet operations, and reduced maintenance due to fewer moving parts [44].
According to the findings of Eudy and Chandler [45], fuel cell electric buses (FCEBs) have higher fuel economy than diesel buses, as indicated in Figure 5. Despite accounting for a tiny proportion of all vehicles on the road, buses have a considerable environmental impact [46]. Fuel cell buses have zero emissions, making them an appealing choice for decreasing urban air pollution [47]. These buses are significantly quieter than regular diesel buses and require less maintenance and refilling. This is due to the buses’ ability to be gathered at a single location for fueling and maintenance under the authority of the fleet operator.
Buses offer a more advantageous choice for accommodating the fuel cell stack, fuel cell storage system, and battery storage in comparison to conventional vehicles, owing to their diminished weight and capacity restrictions [47]. As a result, various vehicle firms and educational institutions have put several initiatives to the test in the hopes of commercializing HFC bus technology. Common barriers to commercialization include the high initial costs of operating fuel cell buses, the longevity of fuel cell power systems, and the cost of recharging hydrogen gas.

Hydrogen Storage System in Passenger Cars

In order to find the best technology for fuel cell buses, Zamora et al. [48] analyzed two technologies (internal combustion engine and fuel cell-driven electric motor). Both technologies rely on hydrogen for vehicle fuel. The comparison was based on several parameters, including CO2 emissions, environmental sensitivity, efficiency, dependability, autonomy, useful life, and cost. Based on this study, it was determined that the technology based on fuel cells was a superior option for extracting the potential energy of hydrogen in relation to the criteria discussed previously.
Bubna et al. [47] reported the development of a fuel cell hybrid bus (FCHB). The FCHB consists of hydrogen tanks, nickel–cadmium (NiCd) liquid-cooled batteries, the HFC system, and an inverter. The fuel cell hybrid bus provided an average efficiency of 42% throughout the normal drive cycle, indicating that the bus’s performance was highly promising. The FCHB, with its battery-heavy hybrid configuration (which runs mainly in battery-alone mode until the state of recharge), resulted in cheaper costs and improved performance and durability, contributing to this good outcome.
Byung and Tae [49] investigated the development of FCVs by Hyundai-Kia Motors, beginning with their first-generation FCV in 2000. The bus was tested during the 2006 World Cup in Germany. The fuel cell was capable of producing a maximum of 160 kW, with an extra capacitor of 80 kW functioning as a backup when needed. The electric motor on this FC bus has a power capability of 240 kW.
In 2006, the Clean Urban Transport for Europe (CUTE) Project concluded, marking the conclusion of a pioneering initiative that involved the simultaneous deployment of a significant fleet of 27 fuel cell buses across nine cities for testing purposes. Saxe et al. [50] published the HFC bus performance data and examined the drive cycle in five different cities. Their findings suggest that the overall fuel cell system efficiency (between 36% and 41%) is relatively high. However, HFC buses consumed more energy than diesel buses. The authors stated that more fuel consumption reductions might be achieved by reducing the weight by up to 2 tons, removing reliability measures, and utilizing hybridization with electrical auxiliaries, which can reduce fuel consumption by up to 35–40%.
In order to research the deterioration process of the HFC system, Li et al. [51] designed a plug-in HFC city bus. The 270 total cells in the 18-ton bus, which was constructed in 2015 and featured a 60 kW power stack, demonstrated power stability on continuous journeys. They concluded that an increase in ohmic polarization mostly caused the voltage drop.
In conjunction with Indian Space Research Organization (ISRO), Tata Motors in India was the first company in the area to create a fuel cell bus. The TATA STAR BUS matches Tata Motors’ long-term objective of manufacturing more environmentally friendly automotive vehicles. The bus could store four high-pressure (350 bar) hydrogen cylinders with a total capacity of 820 L, which were positioned on the roof of the vehicle. With a Li-ion battery, this revolutionary system has a power capacity of 120 kW. For transitory power needs, the battery assists the fuel cell. Tata Motors has already tested two prototypes and is optimistic about commercializing this potentially transformative technology in public transportation [52].
Figure 6 displays the active fuel cell hybrid buses in 2014, with the majority deployed in North America and Europe. These buses have accumulated a successful service record of over 3 million miles [53].
Samsun et al. [24] collected data to determine the total number of registered FCVs worldwide. It was found that there were 34,804 fuel cell vehicles by the end of the year 2020, as shown in Figure 7. Only 16.2% of those vehicles were buses. The distribution of vehicle types across the total number of fuel cell vehicles worldwide can be seen in Figure 8. Of those, it was seen that 97% of the buses were operated in Asia, 2% in Europe, and 1% in North America. China contributes to most of Asia’s fuel cell buses, with a total of 5290 buses. Passenger cars make up most of the world’s fuel cell vehicles, with about 74.5% of total cars.

5. Trains

The energy source for fuel cell-powered trams is hydrogen. A hybrid system combining large-capacity lithium titanate batteries and fuel cells powers the tram. The only pollutants produced by tram operations are heat and water. The tram’s hydrogen fuel is stored in high-pressure tanks on the tram’s roof. Cutting-edge heat dissipation and storage technology boosts hydrogen capacity and cruising range. This fuel cell tram typically has enough fuel to run for more than 13 h every day. Table 2 shows the specifications of the Fashon city tram which has been employed in China [54].
China was one of the pioneers that practically employed a commercial fuel cell-powered tram system in Foshan, a city in Guangdong Province. To take advantage of this chance, the city is developing into a hub for the design and production of hydrogen fuel cell products. It also looks to technology to help the city satisfy its urgent demand for environmentally friendly transportation. Therefore, several hydrogen initiatives have been carried out in Foshan, such as the Foshan Gaoming Modern Hydrogen Tram Demonstration Line, which is perhaps the most well-known of them. In July 2019, the first hydrogen tram was employed in Foshan, and the Foshan Gaoming tram line opened to the general public and began receiving payments in December 2019. During peak hours, the project management team, which is headed by Foshan Metro, expects to operate four trams with departures every 10 min and 115 departures each day. Each tram includes three coach bodies that can accommodate 360 passengers in total, has a top speed of 70 km/h, and has a range of 125 km per refueling [54].
The world’s first HFC train, Coradia iLintTM, was powered by hydrogen in 2016 in Berlin with 160 passenger seats. In the European Union (EU), the majority of the passengers commute by electrified railways, which is about 53%; nevertheless, employing such a system in other countries such as North America is not applicable to this capacity as most of the railway lines are non-electrified [55].
Hsiao et al. [56] developed a hybrid system incorporating a proton exchange membrane fuel cell (PEMFC) into a mini-train capable of accommodating 9–12 passengers. The fuel cell power system employed in this research encompassed a 200-watt PEMFC, four metal hydrogen storage tanks interconnected with a group of low-pressure lead acid batteries, and an intelligent electronic energy control system. Power provision was achieved by means of a parallel connection of fuel cells and lead acid batteries. The mini-train operated outdoors on a track measuring 18.4 cm in width and 212 m in length at the National Science and Technology Museum. Following a two-year implementation period, noteworthy findings were obtained. The small train logged over 2000 h of service and carried over 70,000 passengers during that period [56]. The research illustrated that connecting lead acid batteries and fuel cells in parallel may resist Taiwan’s high heat and humidity while providing stable electricity. This fuel cell power system was capable of providing the same amount of power to the mini-train as lead acid batteries.
Despite the early stage and incomplete development of hydrogen fuel cell (HFC) technology for trains, available literature highlights that hydrogen-powered trains demonstrate a range roughly ten times greater than that of battery-powered electric trains. These trains can achieve top speeds ranging from 125 to 140 km/h and cover distances of up to 1000 km before requiring refueling. Furthermore, the refueling process for these trains takes less than 20 min, signifying a notably rapid procedure.

6. Trucks

HFC technology in medium-duty (MD) and heavy-duty (HD) vehicles has high potency in reducing greenhouse emissions and energy consumption. Globally, heavy-duty trucks produce approximately 36% of nitrogen oxide emissions [57] and 25% of the US transportation sector’s greenhouse gases [58]. Studies conducted by the US Energy Information Administration predict a spike of up to 80% in total miles driven by trucks between 2010–2050 [59]. For this reason, trucks have been a vital parameter to consider when reducing emissions from powertrains. Despite the widespread use of fuel cell technology in cars and buses, its application in trucks is still relatively limited. HFCs have been put forward as a feasible substitute for diesel engines with the aim of reducing pollutant emissions [60]. However, their driving range and performance are still in question. Although the number of hydrogen fuel cell electric trucks, vans, and buses on the road today is limited, several studies have shown that HFC vehicles are crucial for minimizing the effect of climate change by the year 2050 [61].
Integrating the fuel cell system into medium-duty and heavy-duty trucks can be complex due to the effects of the components on the weight and aerodynamics of the trucks. Trucks are classified into several categories. Whether MD or HD vehicles, they are classified based on their designated vocational applications and corresponding weight classes.
Table 3 demonstrates the estimated vehicle population in 2014 [62]. According to Oak Ridge National Laboratory [63], around 10.9 million registered class 3 to 8 vehicles exist. In total, they make up about 5% of on-road vehicles. The most significant number of trucks is the class 8 tractor (60,000 lb. or more), which counts 2.67 million vehicles.
To the best of our knowledge, we compiled a list of the hydrogen-powered trucks that are in operation and expected to be produced in the coming years, as shown in Table 4.
Because of the additional design space, customizability, and weight, utilizing an HFC system in trucks appears to be a potential option, resulting in better scaling and, hence, commercialization. Several studies exist in the literature that discuss the chance of introducing HFC technology and other alternatives to the market, their overall effect on the environment, and their economic impact [65]. Çabukoglu et al. [66] presented a study to determine whether it is possible to decarbonize heavy-duty transport across the entire Swiss national fleet. The scholars also studied the feasibility of day-to-day operations for every vehicle class. A study conducted by Lewis et al. [67] used GPS data to determine the optimal powertrain for given routes and duty cycles. They concluded that a hybrid mechanism comprising a 32 kW HFC, a 49 kWh battery, and a 15 kg hydrogen storage tank should yield an optimal option.
Kast et al. [62] analyzed the design of hydrogen fuel cell trucks in detail and discussed the possibility of onboard storage and the vehicle’s performance under different drive cycles. Storing the hydrogen tanks in the most appropriate location is essential, as this will significantly impact the vehicle’s air resistance due to its shape. There are various places for storing hydrogen tanks on a truck, which vary based on the vocation and truck size [62]. These storages can be categorized as follows:
  • Side-rail tanks: This is the most convenient model, as most MD and HD trucks already have this space available.
  • Back-of-cab storage: This is an option for larger trucks, typically classes 4 to 8.
  • Under the chassis: This is suitable for smaller-class vehicles (e.g., class 3 and below). This configuration can only work for particular trucks because of chassis design constraints, i.e., the tanks do not interfere with the beams.
  • On top of vehicle: This type can only be used on certain trucks and results in a higher center of gravity.
Multiple storage tank locations can be utilized to optimize the trucks’ driving range.
Figure 9 shows an estimated driving range for several vehicles based on optimizing storage tank locations onboard [62]. The payload and hydrogen storage capacity significantly influence the driving range of a high-capacity (HD) vehicle. A completely fueled HD truck, equipped with two storage tanks containing 40–60 kg of hydrogen each at a pressure of 350 bars, generally covers a distance of approximately 500 to 1000 miles before requiring refueling [68].
Kast et al. [62] achieved impressive outcomes in terms of power-to-weight ratio, fuel economy, hydrogen storage, and vehicle range.
Figure 10 displays the calculation of the required hydrogen storage for different trucks to attain a specific driving range, using data extracted from the literature [62]. It can be seen that the trend follows a quadratic fit as the gross vehicle weight rating (GVWR) increases.
The improvement of HFC-powered trucks has grown in interest among manufacturers in the past couple of years. According to Çabukoglu et al. [66], developing hydrogen-powered fuel cell trucks does not only mean building new trucks but also converting them into FCEVs. Converting heavy-duty vehicles is less complex than lighter vehicles, and that is because lighter-duty vehicles (less than 18 tons) have less space to store the hydrogen tanks. More work is needed in terms of infrastructure and the installation and production of hydrogen refueling stations. Fuel congestion and refueling rates are also issues to consider before commercialization. Such a project’s feasibility and cost analysis also need to be studied to prove its sustainability. The aim is to develop sustainable MD/HD trucks that meet the performance requirements while generating zero greenhouse emissions. Assuming that the infrastructure is ready and the feasibility study proves suitable, fuel cell trucks are likely to become the leading form of truck transport due to their zero emissions and extended driving range.

7. Aerial Transportation Systems

The adverse impact of the emissions resulting from burning fossil fuels on the climate is becoming apparent. The aviation industry contributes about 2.1% of global CO2 emissions, and when other pollutants and greenhouse gases are factored in, this figure approaches 5%, making the industry one of the top ten emitters [69]. Noise pollution is another nuisance, especially for communities neighboring major airports around the globe. To tackle these problems, the European Commission, for instance, has set a few environmental targets aiming to reduce CO2 emissions by 75%, NOx gases by 90%, and perceived noise by 65% produced by a typical aircraft compared to the year 2000 levels by the year 2050 [70,71]. Similarly, the International Air Transport Association (IATA) and the International Civil Aviation Organization (ICAO), among other influential entities in the aviation sector, have set a target of attaining a 50% decrease in CO2 emissions by 2050. Such ambitious goals would require a drastic paradigm shift in the aviation industry that cannot be merely achieved by reducing fuel consumption through improvements in aircraft aerodynamics or by designing more efficient engines.
According to a report conducted by McKinsey in 2020 [72], fuel cell technology has the potential to reduce the climate impact of the aviation industry by approximately 75% to 90%. This reduction could take place with a minimal increase in the cost of about USD 5–10 per passenger (PAX) for commuter and regional aircraft, 20–30% per PAX for short-range aircraft, 30–40% per PAX for medium-range aircraft, and 40–50% per PAX for long-range aircraft in comparison with conventional aircraft of the same category. Table 5 presents the definition and classification of the different types of aerial vehicles.
Many researchers have recently been engaged in finding alternative sources of energy, such as lithium ion batteries, fuel cells, or other hybrid architectures, to power aircraft. Zunum, Airbus, Aero, and Eviation are notable companies endeavoring to create short-range passenger aircraft powered solely by electric batteries. These batteries hit the market in 2021 [76]. The limited energy storage density of batteries, which stands at 0.35 kWh∙kg−1, severely constrains the payload and range of all-electric aircraft, although they have the potential to eliminate greenhouse gas emissions caused by air travel [76]. In contrast, fuel cell-based systems offer enhanced performance with regard to range and endurance. The two pivotal factors for aircraft electrification are energy density in Wh/kg and power density in W/kg. The former determines the aircraft’s potential range and passenger-carrying capacity, while the latter plays a crucial role in takeoff and climbing procedures. Figure 11 shows the energy and power densities of various electromechanical energy storage methods.
Small and medium-sized aircraft in the aviation industry are garnering growing attention for the implementation of hydrogen fuel cells, mainly because of their energy efficiency, high energy density, and minimal environmental footprint.
The relationship between HFC technology and the aviation industry is not a recent development. Back in 1932, the English engineer Francis Thomas Bacon created the initial hydrogen–oxygen fuel cell, which marked a significant milestone. This groundbreaking invention proved to be highly effective, leading to its utilization in the space sector to energize satellites and rockets for space exploration initiatives such as Apollo 11 from the 1960s onward [78,79] Recently, leading airplane manufacturers, such as Airbus and Boeing, have been considering using hydrogen fuel cells to replace their aircraft’s traditional auxiliary power units (APUs). An APU is a compact turbine engine that is typically situated in the tail cone of an aircraft or, in certain instances, within an engine nacelle or the wheel well. An APU is present in the majority of contemporary turbojet-powered planes, encompassing smaller regional jets as well as a handful of turboprop aircraft. By propelling the electrical generator, the APU enables the aircraft to function independently without the need for ground support equipment. Consequently, it empowers the aircraft to operate autonomously. With more advances in the technology related to hydrogen fuel cells, such as hydrogen production, storage, and refueling, large commercial airplanes partially propelled by hydrogen fuel cells could become a reality in one or two decades [80].
In general, fuel cell applications in the aviation industry can be classified into propulsive and non-propulsive (i.e., for electric power generation) applications. There are currently many studies and attempts by researchers and aircraft manufacturers to use fuel cells for propulsive and non-propulsive functions in small and medium-sized aircraft as well as UAVs. For large commercial airplanes, however, the current volume of work is focused on using fuel cells for non-propulsive functions.
The next section represents a review of fuel cell applications in propulsive and non-propulsive applications in the aviation industry.

7.1. Fuel Cells for Non-Propulsive Applications (Electric Power Generation)

Most aerial vehicles need electric energy to power their various systems, such as the cabin pressurization unit, lighting, cockpit avionics, the environmental packs used for heating and cooling, etc. This electrical power is generated via a generator, which is driven either by the main engine or by an auxiliary power unit (APU). The main engine and APU mainly rely on fossil fuels as a source of energy.
The increasing pressure on the aircraft manufacturer to reduce emissions, noise, and cost prompted the transition to more electrical aircraft (MEA) options [81,82,83]. This shift meant replacing the main engine/APU-driven generator with direct electric power generation systems, such as batteries, fuel cells, and supercapacitors, as standalone systems or in hybrid combinations. Many researchers regard fuel cell systems as a significant contender for achieving MEAs [83,84,85,86,87,88,89], due to their numerous benefits, which include but are not limited to high efficiency, minimal to no emissions, distributed power generation, and the possibility of water reclamation [90,91]. Several fuel cell forms exist, varying in terms of their operating temperature range and electrolyte composition. These include the solid oxide fuel cell (SOFC), phosphoric acid fuel cell (PAFC), molten carbonate fuel cell (MCFC), molten direct methanol fuel cell (MDMFC), and proton exchange membrane fuel cell (PEMFC). Among these, SOFC and PEMFC have attracted the most attention for applications related to the aviation industry. Table 6 and Figure 12 show the two types’ specs and schematics [92].
Table 6. Characteristics of PEMFC and SOFC [92].
Table 6. Characteristics of PEMFC and SOFC [92].
ParameterPEMFCSOFC
ElectrolyteProton exchange membranesCeramic
Operating temp. 80–100 °C600–1000 °C
Charge carrierH+O2−
Reforming process for HC fuelsExternalPartial external pre-reforming, partial stack-internal
Prime cell componentsCarbon-basedCeramic based
CatalystPlatinumPerovskites/nickel
Robustness against poisoningHighly sensitive to CO, UHC, SSensitive to S
Product H2O managementEvaporativeGaseous product
Product heat managementProcess gas + independent cooling mediumInternal reforming + process gas
H2O effluent locationAir sideFuel side
System efficiency>40%>75% (hybrid SOFC)
Response to load changeQuick, dynamic system behaviorSlow, static system behavior
MaturityFirst operational test series in automotive industryBreadboard units for mobile application
Wevj 14 00156 g012
Figure 12. Schematics of (a) PEMFC, (b) SOFC [93].
Figure 12. Schematics of (a) PEMFC, (b) SOFC [93].
Wevj 14 00156 g012
Shanshan et al. [92] conducted a comparison between solid oxide fuel cells (SOFCs) and proton exchange membrane fuel cells (PEMFCs) in terms of their performance for generating electrical power onboard an MEA. Based on the presented configurations, the authors concluded that SOFC performs better than PEMFC. Whyatt G. et al. [94] investigated the potential of using SOFC for generating electricity on Boeing 787 as a case study. Elamn et al. [90] compared the performance of SOFC-GT and PEMFC-GT hybrid configurations against the conventional gas turbine (GT)-APU. According to the study, the findings indicate that concepts incorporating solid oxide fuel cells (SOFCs) demonstrate significantly higher system efficiencies, suggesting a greater potential to replace conventional auxiliary power unit (APU) systems. Similar work was conducted by Daggett [95] in which SOFC-GT was proposed as a hybrid system on Boeing 777 as a case study. He predicted that the SOFC-GT APU would be 60% efficient at sea level. Rajashekara et al. [85] modeled different hybrid architectures of FC-GT APU in an attempt to find the optimal configuration for generating electrical power on board the 305-seat Boeing 777. The authors concluded that the hybrid SOFC-GT combination is highly attractive. It was predicted to have a fuel efficiency of 73.7% at high altitude and 60.6% at sea level.
In a similar vein, the research conducted by Gummalla et al. [96] examined the performance of the solid oxide fuel cell–gas turbine (SOFC-GT) auxiliary power unit (APU) concept for a 162-passenger, more electric, short-range aircraft with a range of 1000 nautical miles and a peak load of 360 kW. The study estimated that the system could achieve fuel savings of 6.7% compared to the baseline GT APU system. Furthermore, Collins F. et al. [76] investigated the utilization of a hybrid configuration combining SOFC-GT and battery systems for onboard electric power generation in four different aircraft: the Fokker F70, Boeing 787-8, and Airbus models A300 and A380. The hybrid system, comprising the SOFC-GT–battery setup, was optimized to maximize passenger payload when compared to existing turbine technology operating on jet fuel, as well as next-generation turbine technology utilizing liquid hydrogen. The energy and power analysis conducted suggests that the SOFC-GT–battery hybrid configuration could have a significant role to play in future commercial aircraft.

7.2. Fuel Cells for Propulsive Applications

Presently, most large civil aircraft use turbofan engines as their primary power source. Smaller aircraft, such as sport aircraft, commuter aircraft, or AUVs, prefer to use a motor or turbo-propeller engine. The required power for large commercial aircraft is generally above 400 kW, whereas the required power for smaller aircraft is typically in the range of 5–240 kW [84,97,98,99]. For a small electrical UAV to achieve flight, it generally requires a power-to-weight ratio ranging from 20 to 200 watts per kilogram. To provide an example, a UAV with a take-off weight of 4.5 kg and a wingspan of 5 m would necessitate approximately 100 W of power. In contrast, larger UAVs capable of carrying a load of 300 kg might require around 1.5 kW of power. For high-altitude and long-endurance (HALE) UAVs, the power requirement could be in the tens of kWs [100]. Many researchers have presented analytical studies proposing fuel cell technology to provide a propulsive function to different types of aircraft.
Suewatanakul et al. [101] introduced a hybrid mechanism consisting of a proton exchange membrane fuel cell (PEMFC) and a battery for an autonomous underwater vehicle (AUV) aircraft. The UAV in question has a wingspan of 4 m and a maximum take-off weight of 25 kg. Their research findings revealed that by utilizing a 650 W fuel cell in combination with a 100 Wh battery pack and an 80 g compressed hydrogen fuel supply, the aircraft was capable of completing a 2 h journey. Similarly, Farajollahi et al. [102] explored a hybrid propulsion system that incorporates a PEMFC and a battery for a small unmanned aerial vehicle (UAV). Similar work was conducted by Wang et al. [103] in which they investigated the performance of hybrid UAV systems comprising a battery pack and three different types of fuel cells: PEMFC, DMFC, and SOFC.
Qin et al. [104,105] have proposed a SOFC turbine-less jet engine to provide electric propulsion for long-endurance AUVs. In their proposal, the compressor is driven by the SOFC instead of a turbine. Figure 13 shows a schematic of the proposed propulsion system. Different jet fuels were studied to produce the needed hydrogen through a reformer for the SOFC. The following fuels were used: methane, methanol, decane, and propane. The researchers reached the conclusion that the efficiency and specific power of the SOFC jet engine surpass those of combustion engines.
Gonzalez-Espasandin et al. [106] proposed PEMFC and DMFC hybridization concepts with electric batteries for UAVs. The batteries were used to overcome the fuel cells’ lower power density. Marinaro et al. [107] presented a numerical analysis of the propulsion system based on PEMFC as the primary power source as well as a battery backup and ultra-capacitor for a secondary energy source. The PEMFC unit was designed to meet continuous electrical loads during the cruising segment of the flight, and the battery pack was designed to provide an extra energy boost during take-off and climbing. The ultra-capacitor was sized to avoid a high discharge rate of the battery pack and to contribute to the power mix during the maximum power demand. The power management strategy used is shown in Figure 14. The system was designed to generate at least 30 kW. Two power architectures were analyzed: one comprising the battery pack alone and the other made up of the PEMFC and battery pack working in synergy. According to their findings, the hybrid architecture, which consists of PEMFC and a battery pack, provides greater energy density onboard the aircraft.
In conclusion, when it comes to using fuel cells to replace the conventional APUs onboard aircraft, the most promising architecture is the SOFC-GT hybrid system [92,108]. The literature survey showed that SOFC-GT hybrid systems could achieve efficiencies as high as 75%, much higher than the non-hybrid option (maximum of 38%) [108]. Other hybridizations of GT with PEMPC and batteries seem to be less likely. Although PEMFCs’ technology is more mature than SOFCs, SOFCs have some qualities that make them the preferred option for replacing the conventional APU on aircraft. Among these qualities are (i) the possibility of internal fuel reforming for short-chain hydrocarbon fuels such as methane, ethanol, methanol, and natural gas [109], (ii) higher power density, and (iii) greater efficiency [108]. An external reformer would be needed for long-chain hydrocarbon fuels such as gasoline and kerosene [110,111,112]. Reforming fuels requires high temperatures (700–800 °C), which are compatible with the operating temperature of SOFCs (600–1000 °C) but not in the case of PEMFCs (80–100 °C). Furthermore, because SOFCs operate at high temperatures, their hybridization with gas turbine power plants results in high cycle efficiencies [84,85]. Furthermore, it has been reported that, for similar stack power densities, PEMFC is about 50% heavier than SOFC due to the larger PEMFC size, which results in lower system efficiency [90].
Dong et al. [113] conducted a synthesis analysis to implement electric propulsion in large civil aircraft. Seitz et al. [114] proposed a SOFC-GT hybrid concept for the propulsion system of commercial aircraft whereby the byproduct water of SOFCs is injected into the gas turbine to increase its efficiency. The water is converted into superheated steam and injected into the combustion chamber to increase thermodynamic efficiency, as shown in Figure 15.
It is worth mentioning here, however, that the deployment of fuel cells for propulsive applications in the foreseeable future is most likely to take place in UAVs, sport aircraft, commuter aircraft, and regional aircraft. To accommodate the size of the liquid hydrogen (LH2) tanks on medium- and long-range aircraft, the fuselage must be significantly extended. Increasing the size of the fuselage would lead to an increase in fuel consumption of about 25% compared to a conventional aircraft. Therefore, the implementation of fuel cell technology for propulsive function in medium and large aircraft may have to wait until new aircraft designs are made. Such development could be 20 years away. Meanwhile, the use of synthetic fuel (synfuel) is likely to be a more cost-effective solution for reducing emissions [72,115].

8. Conclusions

This article presents a comprehensive examination of the application of hydrogen fuel cell (HFC) technology within the transportation sector, encompassing a wide range of vehicles from bicycles and scooters to commercial airplanes. The analysis provides compelling evidence of the considerable potential for HFC technology to secure a significant portion of the market in this industry by the end of the present decade. The distinct advantages inherent in HFCs, namely zero emissions, compactness, durability, and high efficiency, far outweigh those offered by most alternative energy sources. Conversely, HFCs do encounter several limitations, such as the costliness of catalysts and the relatively low power density, in addition to the challenges associated with hydrogen itself, such as production, storage, and distribution infrastructure.
Among the different types of HFCs, two types were noticed to be the most prevalent: PEMFCs and SOFCs. Due to the similarity of their operating temperatures, PEMFCs are most commonly used in two-wheeled vehicles, cars, drones, and small aircraft, whereas SOFCs are primarily used in large and medium-sized airplanes in hybridization with gas turbines.
The penetration of HFC for propulsion functions in large commercial airplanes would require redesigning the airplanes in order to accommodate the large size of hydrogen tanks needed. Hence, the use of HFCs in large airplanes will be limited to electric power generation in the foreseeable future. To overcome the drawbacks of low power density and the slow response of HFCs, hybridization with ICEs, batteries, and/or supercapacitors is sometimes used.
In conclusion, this study has shed light on the challenges and solutions associated with hydrogen fuel cells in transportation systems. To further guide researchers in this field, it is essential to identify the research gaps and highlight the challenges that need to be addressed. Key areas of focus include understanding the long-term durability and performance of fuel cell systems, evaluating the impact of environmental conditions on efficiency, exploring the economic feasibility and scalability of hydrogen infrastructure, and investigating advanced materials and catalysts. Additionally, challenges such as enhancing onboard hydrogen storage, developing cost-effective production and distribution methods, addressing safety concerns, and integrating fuel cell systems with renewable energy sources have been identified.

Author Contributions

All authors contributed substantially and equally to writing and original draft preparation. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no extra external funding.

Data Availability Statement

As this paper is a review paper, no new data were created in this study.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Cook, B. Introduction to fuel cells and hydrogen technology. Eng. Sci. Educ. J. 2002, 11, 205–216. [Google Scholar] [CrossRef]
  2. Ananthachar, V.; Duffy, J.J. Efficiencies of hydrogen storage systems onboard fuel cell vehicles. Sol. Energy 2005, 78, 687–694. [Google Scholar] [CrossRef]
  3. Bairabathina, S.; Balamurugan, S. Review on non-isolated multi-input step-up converters for grid-independent hybrid electric vehicles. Int. J. Hydrogen Energy 2020, 45, 21687–21713. [Google Scholar] [CrossRef]
  4. Briguglio, N.; Andaloro, L.; Ferraro, M.; Antonucci, V. Fuel Cell Hybrid Electric Vehicles. In Electric Vehicles, The Benefits and Barriers; InTech: London, UK, 2011. [Google Scholar]
  5. Horrell, P. Hyundai Motor Group Tech 2019. The Future Lies in: EV? or FCEV? 2019. Available online: https://fuelcellsworks.com/news/the-future-lies-in-ev-or-fcev/#disqus_thread (accessed on 29 May 2023).
  6. Thomas, C.E. Fuel cell and battery electric vehicles compared. Int. J. Hydrogen Energy 2009, 34, 6005–6020. [Google Scholar] [CrossRef]
  7. Valdés-lópez, V.F.; Mason, T.; Shearing, P.R.; Brett, D.J.L. Carbon monoxide poisoning and mitigation strategies for polymer electrolyte membrane fuel cells—A review. Prog. Energy Combust. Sci. 2020, 79, 100842. [Google Scholar] [CrossRef]
  8. Wang, F.; Kishimoto, H.; Ishiyama, T.; Develos-Bagarinao, K.; Yamaji, K.; Horita, T.; Yokokawa, H. A review of sulfur poisoning of solid oxide fuel cell cathode materials for solid oxide fuel cells. J. Power Sources 2020, 478, 228763. [Google Scholar] [CrossRef]
  9. Franceschini, E.A.; Levitan, D.; Rodriguez, C.R.; Mu, P.; Humana, T.; Correa, G. Comparative analysis of cost, emissions and fuel consumption of diesel, natural gas, electric and hydrogen urban buses. Energy Convers. Manag. 2022, 257, 115412. [Google Scholar] [CrossRef]
  10. Yılmaz, M.; Özdemir, S. Review of Motors used in Commercial Electric Vehicles. In Proceedings of the 5th International Mediterranean Science and Engineering Congress (IMSEC 2020), Antalya, Turkey, 21–23 October 2021. [Google Scholar]
  11. Wang, H.; Gaillard, A.; Hissel, D. A review of DC/DC converter-based electrochemical impedance spectroscopy for fuel cell electric vehicles. Renew. Energy 2019, 141, 124–138. [Google Scholar] [CrossRef]
  12. Staffell, I.; Scamman, D.; Velazquez Abad, A.; Balcombe, P.; Dodds, P.E.; Ekins, P.; Shah, N.; Ward, K.R. The role of hydrogen and fuel cells in the global energy system. Energy Environ. Sci. 2019, 12, 463–491. [Google Scholar] [CrossRef]
  13. Weigl, J.; Inayati, I.; Zind, E.; Said, H. Pios fuel cell motorcycle; design, development and test of hydrogen fuel cell powered vehicle. In Proceedings of the 2008 IEEE International Conference on Sustainable Energy Technologies, Singapore, 24–27 November 2008; pp. 1120–1122. [Google Scholar] [CrossRef]
  14. Weigl, J.D.; Henz, M.; Inayati; Saidi, H. Converted battery-powered electric motorcycle and hydrogen fuel cell-powered electric motorcycle in South East Asia: Development and performance test. In Proceedings of the Joint International Conference on Electric Vehicular Technology and Industrial, Mechanical, Electrical and Chemical Engineering (ICEVT 2015 & IMECE 2015), Surakarta, Indonesia, 4–5 November 2015; pp. 1–4. [Google Scholar] [CrossRef]
  15. Weigl, J.D.; Inayati, I.; Saidi, H. Development of Hydrogen Fuel Cell Motorcycle in South East Asia. ECS Trans. 2011, 30, 289–293. [Google Scholar] [CrossRef]
  16. Hwang, J.J. Review on development and demonstration of hydrogen fuel cell scooters. Renew. Sustain. Energy Rev. 2012, 16, 3803–3815. [Google Scholar] [CrossRef]
  17. Hwang, J.J.; Chang, W.R. Life-cycle analysis of greenhouse gas emission and energy efficiency of hydrogen fuel cell scooters. Int. J. Hydrogen Energy 2010, 35, 11947–11956. [Google Scholar] [CrossRef]
  18. Cox, B.L.; Mutel, C.L. The environmental and cost performance of current and future motorcycles. Appl. Energy 2018, 212, 1013–1024. [Google Scholar] [CrossRef]
  19. Chen, H.S.; Tsai, B.K.; Hsieh, C.M. Determinants of consumers’ purchasing intentions for the hydrogen-electric motorcycle. Sustainability 2017, 9, 1447. [Google Scholar] [CrossRef]
  20. Mellino, S.; Petrillo, A.; Cigolotti, V.; Autorino, C.; Jannelli, E.; Ulgiati, S. A Life Cycle Assessment of lithium battery and hydrogen-FC powered electric bicycles: Searching for cleaner solutions to urban mobility. Int. J. Hydrogen Energy 2017, 42, 1830–1840. [Google Scholar] [CrossRef]
  21. Kheirandish, A.; Kazemi, M.S.; Dahari, M. Dynamic performance assessment of the efficiency of fuel cell-powered bicycle: An experimental approach. Int. J. Hydrogen Energy 2014, 39, 13276–13284. [Google Scholar] [CrossRef]
  22. Bartolozzi, I.; Rizzi, F.; Frey, M. Comparison between hydrogen and electric vehicles by life cycle assessment: A case study in Tuscany, Italy. Appl. Energy 2013, 101, 103–111. [Google Scholar] [CrossRef]
  23. The Future of Hydrogen; International Energy Agency: Paris, France, 2019. [CrossRef]
  24. Samsun, R.C.; Antoni, L.; Rex, M.; Stolten, D. Deployment Status of Fuel Cells in Road Transport: 2021 Update; Forschungszentrum Jülich GmbH Zentralbibliothek: Jülich, Germany, 2021; Volume 542. [Google Scholar]
  25. Statista. Global Transport CO2 Emissions Breakdown 2020. Available online: https://www.statista.com/statistics/1185535/transport-carbon-dioxide-emissions-breakdown/ (accessed on 27 February 2023).
  26. IEA. Electric and Plug-In Hybrid Vehicle Roadmap; IEA: Paris, France, 2010; p. 4. [Google Scholar]
  27. What’s Next for Batteries in 2023. MIT Technology Review. Available online: https://www.technologyreview.com/2023/01/04/1066141/whats-next-for-batteries/ (accessed on 28 February 2023).
  28. Fuel Cell Market Growth Drivers and Opportunities. Size, Share. Available online: https://www.marketsandmarkets.com/Market-Reports/fuel-cell-market-348.html?gclid=EAIaIQobChMI7rnL47q3_QIVUwGLCh37kwc1EAAYASAAEgKwEfD_BwE (accessed on 28 February 2023).
  29. Abdelkareem, M.A.; Sayed, E.T.; Alawadhi, H.; Alami, A.H. Synthesis and testing of cobalt leaf-like nanomaterials as an active catalyst for ethanol oxidation. Int. J. Hydrogen Energy 2020, 45, 17311–17319. [Google Scholar] [CrossRef]
  30. Dell, R.M.; Moseley, P.T.; Rand, D.A.J. Towards Sustainable Road Transport; Elsevier: Amsterdam, The Netherlands, 2014. [Google Scholar] [CrossRef]
  31. Gurz, M.; Baltacioglu, E.; Hames, Y.; Kaya, K. The meeting of hydrogen and automotive: A review. Int. J. Hydrogen Energy 2017, 42, 23334–23346. [Google Scholar] [CrossRef]
  32. Ehsani, M.; Gao, Y.; Longo, S.; Ebrahimi, K. Modern Electric, Hybrid Electric, and Fuel Cell Vehicles, 3rd ed.; CRC Press: Boca Raton, FL, USA, 2018. [Google Scholar] [CrossRef]
  33. Panik, F. Fuel cells for vehicle applications in cars—Bringing the future closer. J. Power Sources 1998, 71, 36–38. [Google Scholar] [CrossRef]
  34. Wilberforce, T.; El-Hassan, Z.; Khatib, F.N.; Al Makky, A.; Baroutaji, A.; Carton, J.G.; Olabi, A.G. Developments of electric cars and fuel cell hydrogen electric cars. Int. J. Hydrogen Energy 2017, 42, 25695–25734. [Google Scholar] [CrossRef]
  35. Moriya, T. Transportation and Safety in Japan. IATSS Res. 2002, 26, 119. [Google Scholar]
  36. Matsunaga, M.; Fukushima, T.; Ojima, K. Powertrain system of honda FCX clarity fuel cell Vehicle. World Electr. Veh. J. 2009, 3, 820–829. [Google Scholar] [CrossRef]
  37. Hong, B.K.; Kim, S.H. (Invited) Recent Advances in Fuel Cell Electric Vehicle Technologies of Hyundai. ECS Meet. Abstr. 2018, MA2018-02, 1630. [Google Scholar] [CrossRef]
  38. Lohse-Busch, H.; Stutenberg, K.; Duoba, M.; Liu, X.; Elgowainy, A.; Wang, M.; Wallner, T.; Richard, B.; Christenson, M. Automotive fuel cell stack and system efficiency and fuel consumption based on vehicle testing on a chassis dynamometer at minus 18 °C to positive 35 °C temperatures. Int. J. Hydrogen Energy 2020, 45, 861–872. [Google Scholar] [CrossRef]
  39. Philip, N.; Ghosh, P.C. A generic sizing methodology for thermal management system in fuel cell vehicles using pinch analysis. Energy Convers. Manag. 2022, 269, 116172. [Google Scholar] [CrossRef]
  40. Berry, G.D.; Pasternak, A.D.; Rambach, G.D.; Smith, J.R.; Schock, R.N. Hydrogen as a future transportation fuel. Energy 1996, 21, 289–303. [Google Scholar] [CrossRef]
  41. Smith, J.R.; Aceves, S.M.; Johnson, N.L.; Amsden, A.A. Progress toward an optimized hydrogen series hybrid engine. In Proceedings of the 95. American Society of Mechanical Engineers` (ASME) Internal Combustion Engin Fall Conference, Milwaukee, WI, USA, 24–27 September 1995. [Google Scholar] [CrossRef]
  42. Sakintuna, B.; Lamari-Darkrim, F.; Hirscher, M. Metal hydride materials for solid hydrogen storage: A review. Int. J. Hydrogen Energy 2007, 32, 1121–1140. [Google Scholar] [CrossRef]
  43. Chalk, S.G.; Miller, J.F.; Wagner, F.W. Challenges for fuel cells in transport applications. J. Power Sources 2000, 86, 40–51. [Google Scholar] [CrossRef]
  44. Zaetta, R.; Madden, B. Hydrogen Fuel Cell Bus Technology State of the Art Review, 2013; No. 245133.
  45. Eudy, L.; Post, M.; Jeffers, M.; Eudy, L.; Post, M.; Jeffers, M. Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Sixth Report; National Renewable Energy Laboratory: Golden, CO, USA, 2017.
  46. Folkesson, A.; Andersson, C.; Alvfors, P.; Alaküla, M.; Overgaard, L. Real life testing of a Hybrid PEM Fuel Cell Bus. J. Power Sources 2003, 118, 349–357. [Google Scholar] [CrossRef]
  47. Bubna, P.; Brunner, D.; Gangloff, J.J.; Advani, S.G.; Prasad, A.K. Analysis, operation and maintenance of a fuel cell/battery series-hybrid bus for urban transit applications. J. Power Sources 2010, 195, 3939–3949. [Google Scholar] [CrossRef]
  48. Zamora, I.; San Martín, J.I.; García, J.; Asensio, F.J.; Oñederra, O.; San Martín, J.J.; Aperribay, V. PEM fuel cells in applications of urban public transport. Renew. Energy Power Qual. J. 2011, 1, 599–604. [Google Scholar] [CrossRef]
  49. Byung, K.A.; Tae, W.L. Fuel cell vehicle development at Hyundai-Kia motors. In Proceedings of the 2006 International Forum on Strategic Technology, Ulsan, Republic of Korea, 18–20 October 2006; pp. 199–201. [Google Scholar] [CrossRef]
  50. Saxe, M.; Folkesson, A.; Alvfors, P. Energy system analysis of the fuel cell buses operated in the project: Clean Urban Transport for Europe. Energy 2008, 33, 689–711. [Google Scholar] [CrossRef]
  51. Li, J.; Hu, Z.; Xu, L.; Ouyang, M.; Fang, C.; Hu, J.; Cheng, S.; Po, H.; Zhang, W.; Jiang, H. Fuel cell system degradation analysis of a Chinese plug-in hybrid fuel cell city bus. Int. J. Hydrogen Energy 2016, 41, 15295–15310. [Google Scholar] [CrossRef]
  52. Basu, S. Proton exchange membrane fuel cell technology: India’s perspective. Proc. Indian Natl. Sci. Acad. 2015, 81, 865–890. [Google Scholar] [CrossRef]
  53. Hua, T.; Ahluwalia, R.; Eudy, L.; Singer, G.; Jermer, B.; Asselin-Miller, N.; Wessel, S.; Patterson, T.; Marcinkoski, J. Status of hydrogen fuel cell electric buses worldwide. J. Power Sources 2014, 269, 975–993. [Google Scholar] [CrossRef]
  54. World’s First Fuel Cell Tram for Foshan, China: World’s First Commercial Fuel Cell Powered Tram Line; Ballard: Burnaby, BC, Canada, 2021.
  55. UIC. Railway Handbook 2017: Energy Consumption and CO2 Emissions; International Energy Agency (IEA) and International Union of Railways (UIC): Paris, France, 2017. [Google Scholar]
  56. Hsiao, D.R.; Huang, B.W.; Shih, N.C. Development and dynamic characteristics of hybrid fuel cell-powered mini-train system. Int. J. Hydrogen Energy 2012, 37, 1058–1066. [Google Scholar] [CrossRef]
  57. US EPA. EPA Air Emissions Inventories. 2015. Available online: https://www.epa.gov/air-emissions-inventories (accessed on 3 February 2023).
  58. U.S. Energy Information Administration. Annual Energy Outlook 2016; U.S. Energy Information Administration: Washington, DC, USA, 2016.
  59. U.S. Energy Information Administration. Annual Energy Outlook 2015 with Projections to 2040; U.S. Energy Information Administration: Washington, DC, USA, 2015.
  60. Vision for Clean Air: A Framework for Air Quality and Climate Planning. 2012. Available online: https://www.aqmd.gov/docs/default-source/clean-air-plans/air-quality-management-plans/2012-air-quality-management-plan/vision-for-clean-air-2012/draft-vision-for-clean-air-a-framework-for-air-quality-and-climate-planning.pdf?sfvrsn=4 (accessed on 3 February 2023).
  61. Williams, J.H.; Haley, B.; Kahrl, F.; Moore, J.; Jones, A.D.; Torn, M.S.; McJeon., H. Pathways to Deep Decarbonization in the United States. 2014. Available online: https://ethree.com/publications/index_US2050.php (accessed on 3 February 2023).
  62. Kast, J.; Morrison, G.; Gangloff, J.J.; Vijayagopal, R.; Marcinkoski, J. Designing hydrogen fuel cell electric trucks in a diverse medium and heavy duty market. Res. Transp. Econ. 2018, 70, 139–147. [Google Scholar] [CrossRef]
  63. Davis, S.C.; Diegel, S.W.; Boundy, R.G. Transportation Energy Futures; the Oak Ridge National Laboratory Oak Ridge: Oak Ridge, TN, USA, 2015; p. 37831-6073. Available online: https://tedb.ornl.gov/ (accessed on 13 February 2023).
  64. H2-Share Project Home Trucks News & Events Documents about Stakeholders Contact in Operation Planned Concept. 2023. Available online: https://fuelcelltrucks.eu/project/ (accessed on 13 February 2023).
  65. Kast, J.; Vijayagopal, R.; Gangloff, J.J.; Marcinkoski, J. Clean commercial transportation: Medium and heavy duty fuel cell electric trucks. Int. J. Hydrogen Energy 2017, 42, 4508–4517. [Google Scholar] [CrossRef]
  66. Çabukoglu, E.; Georges, G.; Küng, L.; Pareschi, G.; Boulouchos, K. Fuel cell electric vehicles: An option to decarbonize heavy-duty transport? Results from a Swiss case-study. Transp. Res. Part D Transp. Environ. 2019, 70, 35–48. [Google Scholar] [CrossRef]
  67. Lewis, M.; Hearn, C.; Feng, X.; Hanlin, J.; Levin, J.; Ambrosio, J.; Guggenheim, P.; Walker, C. Design and modeling for hydrogen fuel cell conversion of parcel delivery trucks. In Proceedings of the 2017 IEEE Transportation Electrification Conference and Expo (ITEC), Chicago, IL, USA, 22–24 June 2017; pp. 674–678. [Google Scholar] [CrossRef]
  68. Cunanan, C.; Tran, M.K.; Lee, Y.; Kwok, S.; Leung, V.; Fowler, M. A Review of Heavy-Duty Vehicle Powertrain Technologies: Diesel Engine Vehicles, Battery Electric Vehicles, and Hydrogen Fuel Cell Electric Vehicles. Clean Technol. 2021, 3, 474–489. [Google Scholar] [CrossRef]
  69. Carbon Market Watch. Climate Action Network and International Coalition for Sustainable Aviation Joint Input to the Talanoa Dialogue. Available online: https://carbonmarketwatch.org/publications/climate-action-network-and-international-coalition-for-sustainable-aviation-joint-input-to-the-talanoa-dialogue/ (accessed on 7 October 2022).
  70. ICAO Environmental. Trends in Emissions That Affect Climate Change. Available online: https://www.icao.int/environmental-protection/Pages/ClimateChange_Trends.aspx (accessed on 8 October 2022).
  71. European Commission. Reducing Emissions from Aviation. Available online: https://climate.ec.europa.eu/eu-action/transport-emissions/reducing-emissions-aviation_en (accessed on 8 October 2022).
  72. Hydrogen-Powered Aviation; Publications Office: Luxembourg, 2020. [CrossRef]
  73. Federal Aviation Administration (FAA). SPORT PILOT & AIRCRAFT Affo Fun g Flyin. 2008. Available online: www.AIR-PROS.com (accessed on 29 October 2022).
  74. Federal Aviation Administration. Small Airplanes. Available online: https://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/categories (accessed on 29 October 2022).
  75. IATA Air Transport & Travel Industry. XML Implementation Guide; International Air Transport Association: Montreal, QC, Canada, 2010. [Google Scholar]
  76. Collins, J.M.; McLarty, D. All-electric commercial aviation with solid oxide fuel cell-gas turbine-battery hybrids. Appl. Energy 2020, 265, 114787. [Google Scholar] [CrossRef]
  77. Misra, A. Energy storage for electrified aircraft: The need for better batteries, fuel cells, and supercapacitors. IEEE Electrif. Mag. 2018, 6, 54–61. [Google Scholar] [CrossRef]
  78. BBC Archive. The Brits Who Bolstered the Moon landings. Available online: https://www.bbc.co.uk/archive/the-brits-who-bolstered-the-moon-landings/zfcrscw (accessed on 30 September 2022).
  79. NASA. Space Applications of Hydrogen and Fuel Cells. 2015. Available online: http://www.nasa.gov/content/space-applications-of-hydrogen-and-fuel-cells (accessed on 9 October 2022).
  80. Baroutaji, A.; Wilberforce, T.; Ramadan, M.; Olabi, A.G. Comprehensive investigation on hydrogen and fuel cell technology in the aviation and aerospace sectors. Renew. Sustain. Energy Rev. 2019, 106, 31–40. [Google Scholar] [CrossRef]
  81. Masiol, M.; Harrison, R.M. Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review. Atmos. Environ. 2014, 95, 409–455. [Google Scholar] [CrossRef] [PubMed]
  82. Handbook for Evaluating Emissions and Costs of APUs and Alternative Systems; Airport Cooperative Research Program; Transportation Research Board: Washington, DC, USA, 2012.
  83. Braun, R.J.; Gummalla, M.; Yamanis, J. System architectures for solid oxide fuel cell-based auxiliary power units in future commercial aircraft applications. J. Fuel Cell Sci. Technol. 2009, 6, 0310151–03101510. [Google Scholar] [CrossRef]
  84. Chinda, P.; Brault, P. The hybrid solid oxide fuel cell (SOFC) and gas turbine (GT) systems steady state modeling. Int. J. Hydrogen Energy 2012, 37, 9237–9248. [Google Scholar] [CrossRef]
  85. Rajashekara, K.; Grieve, J.; Daggett, D. A feasibility study for onboard power generation using a combination of solid oxide fuel cells and gas turbines. IEEE Ind. Appl. Mag. 2008, 14, 54–60. [Google Scholar] [CrossRef]
  86. Daggett, D. Product Development, Boeing Fuel Cell APU Overview. In Proceedings of the SECA Annual Meeting, Seattle, WA, USA, 15 April 2003. [Google Scholar]
  87. Barelli, L.; Bidini, G.; Ottaviano, A. Part load operation of a SOFC/GT hybrid system: Dynamic analysis. Appl. Energy 2013, 110, 173–189. [Google Scholar] [CrossRef]
  88. Dollmayer, J.; Bundschuh, N.; Carl, U.B. Fuel mass penalty due to generators and fuel cells as energy source of the all-electric aircraft. Aerosp. Sci. Technol. 2006, 10, 686–694. [Google Scholar] [CrossRef]
  89. Spencer, K.M.; Martin, C.A. Investigation of Potential Fuel Cell Use in Aircraft; Institute for Defense Analyses: Alexandria, VA, USA, 2013. [Google Scholar]
  90. Eelman, S.; Poza, I.D.P.D.; Krieg, T. Fuel Cell Apu’s in Commercial Aircraft—An Assessment of Sofc and Pemfc Concepts. In Proceedings of the 24th International Congress of the Aeronautical Sciences, Yokohama, Japan, 29 August–3 September 2004. [Google Scholar]
  91. Baharozu, E.; Soykan, G.; Baris Ozerdem, M. Future aircraft concept in terms of energy efficiency and environmental factors. Energy 2017, 140, 1368–1377. [Google Scholar] [CrossRef]
  92. Wu, S.; Li, Y. Fuel cell applications on more electrical aircraft. In Proceedings of the 2014 17th International Conference on Electrical Machines and Systems (ICEMS), Hangzhou, China, 22–25 October 2014; pp. 198–201. [Google Scholar] [CrossRef]
  93. Wikipedia. Fuel Cell. 2021. Available online: https://en.wikipedia.org/wiki/Fuel_cell (accessed on 29 October 2022).
  94. Whyatt, G.A.; Chick, L.A. Electrical Generation for More-Electric Aircraft Using Solid Oxide Fuel Cells; U.S. Department of Energy: Washington, DC, USA, 2012; 110p.
  95. Daggett, D. Fuel Cells & Hydrogen Airplanes. In Proceedings of the Canada and US Fuel Cell & Hydrogen Partner Meeting, Seattle, WA, USA, 14–17 July 2003. [Google Scholar]
  96. Gummalla, M.; Pandy, A.; Braun, R.; Carriere, T.; Yamanis, J.; Vanderspurt, T.; Hardin, L.; Welch, R. Fuel Cell Airframe Integration Study for Short-Range Aircraft; NASA/CR—2006-214457/VOL1; NASA: Hanover, MD, USA, 2006.
  97. Sehra, A.K.; Whitlow, W. Propulsion and power for 21st century aviation. Prog. Aerosp. Sci. 2004, 40, 199–235. [Google Scholar] [CrossRef]
  98. Freeh, J.E.; Steffen, C.J.; Larosiliere, L.M. Off-Design Performance Analysis of a Solid-Oxide Fuel Cell/Gas Turbine Hybrid for Auxiliary Aerospace Power. In Proceedings of the ASME 2005 3rd International Conference on Fuel Cell Science, Engineering and Technology, Ypsilanti, MI, USA, 23–25 May 2005; pp. 265–272. [Google Scholar] [CrossRef]
  99. Winkler, W.G.; Nehter, P.; Winkler, W.; Nehter, P.; Winkler, W. System analysis of Fuel Cell APUs for Aircraft applications. In Proceedings of the Workshop 1—Aerospace Applications, Hamburg, Germany, 31 August–1 September 2005; pp. 1–16. [Google Scholar]
  100. Bertran, E.; Sanchez-Cerda, A. On the Tradeoff between Electrical Power Consumption and Flight Performance in Fixed-Wing UAV Autopilots. IEEE Trans. Veh. Technol. 2016, 65, 8832–8840. [Google Scholar] [CrossRef]
  101. Suewatanakul, S.; Porcarelli, A.; Olsson, A.; Grimler, H.; Chiche, A.; Mariani, R.; Lindbergh, G. Conceptual Design of a Hybrid Hydrogen Fuel Cell/Battery Blended-Wing-Body Unmanned Aerial Vehicle—An Overview. Aerospace 2022, 9, 275. [Google Scholar] [CrossRef]
  102. Farajollahi, A.H.; Rostami, M.; Marefati, M. A hybrid-electric propulsion system for an unmanned aerial vehicle based on proton exchange membrane fuel cell, battery, and electric motor. Energy Sources Part A Recover. Util. Environ. Eff. 2022, 44, 934–950. [Google Scholar] [CrossRef]
  103. Wang, B.; Zhao, D.; Li, W.; Wang, Z.; Huang, Y.; You, Y.; Becker, S. Current technologies and challenges of applying fuel cell hybrid propulsion systems in unmanned aerial vehicles. Prog. Aerosp. Sci. 2020, 116, 100620. [Google Scholar] [CrossRef]
  104. Ji, Z.; Qin, J.; Cheng, K.; Guo, F.; Zhang, S.; Dong, P. Comparative performance analysis of solid oxide fuel cell turbine-less jet engines for electric propulsion airplanes: Application of alternative fuel. Aerosp. Sci. Technol. 2019, 93, 105286. [Google Scholar] [CrossRef]
  105. Ji, Z.; Qin, J.; Cheng, K.; Liu, H.; Zhang, S.; Dong, P. Thermodynamic analysis of a solid oxide fuel cell jet hybrid engine for long-endurance unmanned air vehicles. Energy Convers. Manag. 2019, 183, 50–64. [Google Scholar] [CrossRef]
  106. González-Espasandín, Ó.; Leo, T.J.; Navarro-Arévalo, E. Fuel Cells: A Real Option for Unmanned Aerial Vehicles Propulsion. Sci. World J. 2015, 2015, 419786. [Google Scholar] [CrossRef]
  107. Leonov, S.; Marinaro, G.; Di Lorenzo, G.; Pagano, A. From a Battery-Based to a PEM Fuel Cell-Based Propulsion Architecture on a Lightweight Full Electric Aircraft: A Comparative Numerical Study. Aerospace 2022, 9, 408. [Google Scholar] [CrossRef]
  108. Fernandes, M.D.; De, S.T.; Bistritzki, V.N.; Fonseca, R.M.; Zacarias, L.G.; Gonçalves, H.N.C.; de Castro, A.F.; Domingues, R.Z.; Matencio, T. SOFC-APU systems for aircraft: A review. Int. J. Hydrogen Energy 2018, 43, 16311–16333. [Google Scholar] [CrossRef]
  109. Laosiripojana, N.; Assabumrungrat, S. Catalytic steam reforming of methane, methanol, and ethanol over Ni/YSZ: The possible use of these fuels in internal reforming SOFC. J. Power Sources 2007, 163, 943–951. [Google Scholar] [CrossRef]
  110. Aicher, T.; Lenz, B.; Gschnell, F.; Groos, U.; Federici, F.; Caprile, L.; Parodi, L. Fuel processors for fuel cell APU applications. J. Power Sources 2006, 154, 503–508. [Google Scholar] [CrossRef]
  111. Santin, M.; Traverso, A.; Magistri, L.; Massardo, A. Thermoeconomic analysis of SOFC-GT hybrid systems fed by liquid fuels. Energy 2010, 35, 1077–1083. [Google Scholar] [CrossRef]
  112. Shi, L.; Bayless, D.J. Analysis of jet fuel reforming for solid oxide fuel cell applications in auxiliary power units. Int. J. Hydrogen Energy 2008, 33, 1067–1075. [Google Scholar] [CrossRef]
  113. Dong, Q.; Ma, C. Synthesis analysis of electric propulsion implement in large civil aircraft. J. Phys. Conf. Ser. 2022, 2252, 012021. [Google Scholar] [CrossRef]
  114. Seitz, A.; Nickl, M.; Troeltsch, F.; Ebner, K. Initial Assessment of a Fuel Cell-Gas Turbine Hybrid Propulsion Concept. Aerospace 2022, 9, 68. [Google Scholar] [CrossRef]
  115. Perea-Moreno, A.-J.; Meloni, E.; Vilardi, G.; Carlos, J.; Pires, M.; Skov, I.R.; Belikov, J. Use of Sustainable Fuels in Aviation—A Review. Energies 2022, 15, 2440. [Google Scholar] [CrossRef]
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Figure 1. A configuration of fuel cell electric vehicle (FCEV).
Figure 1. A configuration of fuel cell electric vehicle (FCEV).
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Figure 2. Improvement of Honda HFC vehicles [35].
Figure 2. Improvement of Honda HFC vehicles [35].
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Figure 3. Midsized automobiles with less than 2kW battery capacity: (a) Honda FCX clarity, (b) Hyuandi Tucson/ix35 FC, (c) Toyota Mirai I (d) Honda clarity FC, (e) Hyuandi Nexo, (f) Mercedes Benz F-Cell, (g) Chevrolet Equinox Fuel Cell, (h) Toyota Mirai II.
Figure 3. Midsized automobiles with less than 2kW battery capacity: (a) Honda FCX clarity, (b) Hyuandi Tucson/ix35 FC, (c) Toyota Mirai I (d) Honda clarity FC, (e) Hyuandi Nexo, (f) Mercedes Benz F-Cell, (g) Chevrolet Equinox Fuel Cell, (h) Toyota Mirai II.
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Figure 4. Onboard hydrogen fuel system for fuel cell vehicles [43].
Figure 4. Onboard hydrogen fuel system for fuel cell vehicles [43].
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Figure 5. The mean fuel efficiency of fuel cell buses and diesel buses [45].
Figure 5. The mean fuel efficiency of fuel cell buses and diesel buses [45].
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Figure 6. Active fuel cell bus projects globally [53].
Figure 6. Active fuel cell bus projects globally [53].
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Figure 7. Fuel cell vehicle distribution of all vehicles by the end of 2020 [24].
Figure 7. Fuel cell vehicle distribution of all vehicles by the end of 2020 [24].
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Figure 8. Distribution of fuel cell buses across continents [24].
Figure 8. Distribution of fuel cell buses across continents [24].
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Figure 9. The range of the vehicle determined by the placement of the compressed hydrogen storage tank at a pressure of 350 bar [62].
Figure 9. The range of the vehicle determined by the placement of the compressed hydrogen storage tank at a pressure of 350 bar [62].
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Figure 10. The required quantity of hydrogen storage necessary to attain a specific range for each representative truck is estimated based on the gross vehicle weight rating (GVWR) [62].
Figure 10. The required quantity of hydrogen storage necessary to attain a specific range for each representative truck is estimated based on the gross vehicle weight rating (GVWR) [62].
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Figure 11. Comparison between various electromechanical storage structures according to the power and energy densities [77].
Figure 11. Comparison between various electromechanical storage structures according to the power and energy densities [77].
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Figure 13. Schematic of SOFC turbine-less jet engine as proposed by [104].
Figure 13. Schematic of SOFC turbine-less jet engine as proposed by [104].
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Figure 14. Schematic of the power management strategy used by [107].
Figure 14. Schematic of the power management strategy used by [107].
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Figure 15. Schematic of SOFC-GT architecture studied by [115].
Figure 15. Schematic of SOFC-GT architecture studied by [115].
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Table 1. Comparison of a few features of some HFC automobiles, including power outputs and prices.
Table 1. Comparison of a few features of some HFC automobiles, including power outputs and prices.
Production YearVehicle ModelRange (km/Miles)Power Output (kW/hp)Hydrogen Tank Weight (kg)/Capacity (L)Price
2008Honda FCX Clarity [36]450/270100/1344.1/171USD 34,995
2013Hyundai Tucson/ix35 Fuel Cell [37]415/258124/-5.64/140-
2014Toyota Mirai I [38]502/312114/1535/122USD 57,500
2016Honda Clarity Fuel Cell—FCEV740/460105/-NA
2018Hyundai Nexo [37]609/378135/-6.3/156USD 59,435
2010Mercedes Benz B-Class F-CELL [30]400/250100/1363.7/--
2007Chevrolet Equinox Fuel Cell [30]320/20094/1264.2/--
2020Toyota Mirai II [39]650/404128/182NAUSD 49,500
Table 2. Specifications of the Fashon city tram employed in China [54].
Table 2. Specifications of the Fashon city tram employed in China [54].
ConfigurationThree Coaches and Two Locomotives
Size35.19 m × 2.65 m × 3.58 m
Mass55 tons
Max Passenger Capacity360 people
Max Speed70 km/h
Max Range125 km
Daily Operation13 h
Refueling Events2–3 times/day
Refueling Time15 min
Hydrogen Consumption25–30 kg/100 km
Table 3. Estimated vehicle population in 2014; the heat map shows the relative market share per vehicle category of MHDVs [62].
Table 3. Estimated vehicle population in 2014; the heat map shows the relative market share per vehicle category of MHDVs [62].
Class888876543Total
Weight
(lbs. 103)		60 +50–6040–5033–4026–3319.5–2616–19.514–1610–14
VansStepWevj 14 00156 i0012112512710198234572
EnclosedWevj 14 00156 i0024414188729417880256933
InsulatedWevj 14 00156 i0032346406023721167
Open topWevj 14 00156 i00462269387889191211345
Other 1121420714390
Work VehiclesFlatbedWevj 14 00156 i0053341811002034751571853411617
DumpWevj 14 00156 i006203160187101181315801142041546
ConcreteWevj 14 00156 i0071224917200020193
TowWevj 14 00156 i008247111678313665249
UtilityWevj 14 00156 i009271131731067046117465
GarbageWevj 14 00156 i010327349262014625229
FreightTankWevj 14 00156 i0111928514113096141313405
BeverageWevj 14 00156 i01200284632534100
TractorWevj 14 00156 i013267031427913164310003489
Other 29212415401044969151502
Table 4. The characteristics of different hydrogen-powered trucks employed in Europe [64].
Table 4. The characteristics of different hydrogen-powered trucks employed in Europe [64].
ManufacturerRange (km)Max Gross WeightType of TruckFuel Cell Capacity H2 StorageOperation StatusNumber of Trucks
VDL 40027 tonsTruck trailer88 kw30 kg @ 350 barIn operation since 20201
Scania/Asko400–50027 tonsTruck trailer90 kw33 kg @ 350 barIn operation since 20204
E-trucks Europe40026 tonsRefuse truck40 kw--1
SYMBIO: Renault Maxity H22004.5 tons 20 kwTwo tanks with 75 L, each one can store 4 kg of hydrogen with 350 barIn operation1
ESORO375–40034 tons combined with trailerHeavy duty truck100 kw31 kg @ 350 barStarted 2017.
Not operational anymore		1
Nikola Motors805–120036 tonsClass 8—sleeper cab semi-truck--Concept—expected operation in 2022–20231
LOOP Energy--Yard truck (off-road heavy duty)56 kw-In operation1
DONGFENG3307.5 tonsBox van truck30 kw-In operation since 2018500
SCANIA/Renova--Refuse truck--Concept1
Kenworth32036 tonsClass 8—truck trailer85 kw-In operation1
UPS20012 tonsClass 6—Delivery truck31 kw2 × 5 kg, high-pressure tanksIn operation17
PLUGPOWER430-Off-road truck20 kw-In operation15
TOYOTA/HINO60025 tonsClass 8—heavy duty-Developing a new large-capacity, high-pressure (70 MPa) hydrogen tankConcept-
MITSUBISHI FUSO270–3007.5 tonsRigid truck—light duty75 kw5–10 kg @ 700 barIn operation150
Table 5. Aerial vehicle (AV) categories and definitions.
Table 5. Aerial vehicle (AV) categories and definitions.
Type of the AVDefinitionNumber of PassengersConventional Propulsion Type
UAVA drone, also referred to as an unmanned aerial vehicle (UAV), is an aircraft operated remotely.0Battery
Reciprocating engine
Sport Aircraft [73]It is an aircraft other than a helicopter or powered lift with a maximum gross weight of 650 kg (300 lbs) unpressurized cabin.Max 2Single reciprocating engine
Commuter Aircraft [74]A commuter aircraft is primarily used by businesspeople for short-distance travel and has a maximum take-off mass of 8620 kg.Max 19Multiple jet engines
Transport aircraft [75]A transport aircraft refers to an airplane with multiple engines that has a seating capacity exceeding 19 or a maximum take-off weight surpassing 8620 kg (19,000).
The category includes:
  • Short-range aircraft (<3 flight h);
  • Medium-range aircraft (3–6 flight h);
  • Long-range aircraft (6–16 flight h);
  • Ultra-long haul (>16 flight h).
Regional aircraft fit under the short- to medium-range category.
Regional aircraft are typically jet and turboprop aircraft, with a seating capacity ranging from 19 to 130 seats, operating on short- to medium-haul routes.		More than 19Multiple jet engines
Turboprop engines
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Fakhreddine, O.; Gharbia, Y.; Derakhshandeh, J.F.; Amer, A.M. Challenges and Solutions of Hydrogen Fuel Cells in Transportation Systems: A Review and Prospects. World Electr. Veh. J. 2023, 14, 156. https://doi.org/10.3390/wevj14060156

AMA Style

Fakhreddine O, Gharbia Y, Derakhshandeh JF, Amer AM. Challenges and Solutions of Hydrogen Fuel Cells in Transportation Systems: A Review and Prospects. World Electric Vehicle Journal. 2023; 14(6):156. https://doi.org/10.3390/wevj14060156

Chicago/Turabian Style

Fakhreddine, Omar, Yousef Gharbia, Javad Farrokhi Derakhshandeh, and A. M. Amer. 2023. "Challenges and Solutions of Hydrogen Fuel Cells in Transportation Systems: A Review and Prospects" World Electric Vehicle Journal 14, no. 6: 156. https://doi.org/10.3390/wevj14060156

APA Style

Fakhreddine, O., Gharbia, Y., Derakhshandeh, J. F., & Amer, A. M. (2023). Challenges and Solutions of Hydrogen Fuel Cells in Transportation Systems: A Review and Prospects. World Electric Vehicle Journal, 14(6), 156. https://doi.org/10.3390/wevj14060156

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