Analytical review of hydrogen projects on the world’s railways
The transport sector accounts for 25% of the world’s energy consumption in developed countries, showing a strong connection between energy use and economic growth. As a result, the transport sector is responsible for 15 to 31% of global man-made carbon emissions.
Rail is the most sustainable mode of transport. Increasing its share of passengers and freight is critical to achieving net-zero goals. It is one of the most energy-efficient transport modes, responsible for 9% of global motorized passenger movement and 7% of freight shipping—but only 3% of transport energy use, according to the International Energy Agency. It uses 80% less energy than trucks per ton of freight carried and holds a four-to-one advantage over cars in terms of its emissions intensity. As a result, rail accounted for just 4% of the transport industry’s global emissions (BCG, IEA 2019). Quantified by 2022, 320 Mt CO2 in 8 Gt of global transportation sector emissions.
According to the IEA for 2019-2020, 70% of the locomotive fleet runs on diesel or diesel-electric power. About 55% of the energy consumed by the global rail industry was generated by diesel (85% of it used to power trains). Close to 50% of all trains in Western Europe and Asia are diesel powered, 75% in the Middle East and Africa, and a daunting 99% in the Americas. Direct decarbonization for Scope 1 emissions of this sector can be achieved through conversion to battery and/or hydrogen fuel cells (Fuel Cell Hybrid PowerPack, FСНPP), including hybrids with contact line , depending on specific local conditions and tasks of use. It also cannot be ruled out that the conversion of part of the existing locomotives to synthetic and biodiesel will take its share. Thus, hydrogen fuel cells in the global locomotive fleet compete with other low-carbon solutions for 200 MtC02/year Scope 1.
Below an overview of existing and planned models and modifications of hydrogen fuel cell locomotives of the most common PEMFC type, as well as their empirical operational characteristics. Around the world at mid of 2023, there are 16 hydrogen commuter trains deployed, 61 more in manufacturing stages, and several hydrogen locomotive projects; see Table 2 (https://doi.org/10.3390/en16186715). While the research and development for several alternative propulsion concepts is still in its infancy, hydrogen for rail use is already available around the world.
Currently, the implementation of PEMFC on railroads in the EU has reached the level of empirical performance modeling using a geospatial map for different train weights and stopping modes on the route. The net power at wheels covered by the fuel cell system is determined, ranging from 82 kW to 674 kW. In turn, the usable battery capacity ranges from 90 to 274 kWh. These requirements cover the tractive power requirements at wheel level without taking auxiliary loads and efficiency into account. The use of geodata allows the energy of regenerative and augmented loads to be taken into account for an actual fuel demand calculation. https://elib.dlr.de/186770/
Currently, the main problems in operation are related with technical failures of the refueling infrastructure, interruptions in hydrogen supply, high cost of operation compared with the battery scheme. There is limited data available in regards to degradation of PEMFCs in both single cell and stack configurations. Furthermore, degradation data available in academic literature is not always consistent. PEMFC degradation data should also be separated into steady-state and transient degradation. However, the data in this area is sparse. In the absence of additional steady state, stack, and in-service degradation data, it was anticipated that the FC will be able to operate for 20,000–30,000 h. Transient operation has large impacts on FC lifespan compared to steady-state operation.
Coradia iLint is the first hydrogen fuel-cell-powered passenger train designed by French borned Alstom. A total of two prototype trains went through field tests on the Elbe–Weser network in Lower Saxony, Germany in September 2018 and traveled over 180,000 km on a regular passenger service track. A record of 1175 km without refueling was set by the Germans. The two-car train is equipped with two roof-tanks, each with 12 cylinders of 93 kg H2 each is rated at 350 bar. There is one fuel cell mounted on the roof of each car. Both provide electricity for the two main traction motors, each rated at 314 kW. Maximal operation speed is 140 km/h. The total cost of the project is around 93 million euros Coradia iLint. With full tanks the Coradia iLint has a range of between 600 and 800 km, depending on passenger loading, the number of stops, gradient and other route characteristics which govern fuel consumption. A record of 1175 km without refueling was set by the Germans. Additionally, a total of 14 fuel cell trains were deployed in Bremervörde, Lower Saxony in August 2022, following the success of hydrogen-fueled passenger train tests in Germany.
Also trials outside Germany were carried out in UK, Denmark, Norway, Sweden, Italy, the Netherlands, Canada, Austria, and France. The few hydrogen trains delivered in Lower Saxony didn’t work well in December 2022 temperatures of -10C, not unusually cold for German in mid-winter. Only two of the six trains were actually working on some days. The exact operating problems have not been revealed, but the German rail train press reports that putting hydrogen fuel into the trains at low temperatures was a key problem. For the fleet near Frankfurt, operating under rules requiring its hydrogen fuel tanks to be kept at least one-third full at all times, this was made more difficult because the fueling station is inside a chemical works. Having to return there regularly to top up fuel was taking time and engineers that the operating company hadn’t planned for. Now a year after the commercial launch, the Lower Saxony state ministry has abandoned ideas for future hydrogen trains, arguing that battery-electric models “are cheaper to operate” Examining the arguments we come to the conclusion that the rejection of iLint trains is mainly due to local specifics, for example, electrification of a part of not long enough routes with frequent stops. Such tasks can be handled by the battery scheme, which is cheaper in initial and operating costs.
Flirt H2 – The Swiss manufacturer’s Stadler most well-contracted Fast Light Intercity and Regional Train (FLIRT) was unveiled in August 2022 in California for the operator Caltrans 4 trains hard ordered for $80 mln and 24 as option for future supply. This is a landmark entry by a European locomotive manufacturer into the American gauge market. In Jule Stadler has been awarded two framework agreements to supply for €200 mln and maintain 10 hydrogen-powered trains for Azienda Regionale Sarda Trasporti (ARST) in Sardinia and 15 similar trains for Ferrovie della Calabria (FdC) in Calabria. These trains will be the first narrow-gauge (900 mm) hydrogen trains in the world. Should be noticed also, Austrian Federal Railways (ÖBB) has awarded Stadler a framework agreement for up to 120 battery-powered trains. The FLIRT Akku vehicles are designed to replace the current diesel fleet and will enable sustainable operation on lines that are only partially electrified. Flirt H2 is a two-car unit with 6 FCmove- HD+ (Fuell Cell, Heavy-Duty) each with a 100 kW power. They were produced by Ballard Power Systems of Canada and provide maximum traction power 700 kW. The Hydrogen Storage System (HSS) is rated at 350 bar, providing a range of approximately 460 km and maximal speed 127 km/h for 120 pax.
Mireo Plus H – is a second-generation hydrogen train, based on a hybrid technology consisting of two roof-mounted fuel cells Ballard 200 kW and lithium titanate batteries under the vehicle floo. They provide 1.7 MW of traction power for a maximum speed of 160 km/h and operating range of between 1000 and 1200 km. It has two separate tanks for 180 kg +20 kg constant reserve of hydrogen per tank load, which is refueled at up to 500 bar. Siemens Mobility (SM) and national German operator DB unveiled the Mireo Plus H and a new hydrogen storage tank trailer at the Siemens Mobility plant in Krefeld, Germany, in May 2022. Designed by DB, the hydrogen storage tank trailer is equipped with a smart control unit to enable fast refuelling of hydrogen trains. SM has been awarded a contract to deliver 28 three-car electric Mireo regional trains to Baden-Württemberg for the Digital Rail Germany (DSD) Digital Node Stuttgart pilot project. Siemens has a total of 61 Mireo Plus H in its order books, including a project in Denmark.
Fuxing – The world’s largest by revenue rolling stock manufacturer, Chinese СRRС, unveiled hydrogen train in May 2023 at China Brand Day in Shanghai. It seems to be a halved version of the eight-car CR400BF-C train used in the Beijing Olympics. This is a train of the Fuxing Intelligent family, the numbers denote the maximum speed. The CR-type, equipped with the automatic train control system (GoA2), performs the functions of waking up, starting, stopping and returning to the depot. Monitoring sensors monitor the operation and status of the entire train, while 5G connectivity serves for data transmission. The train uses a combination of hydrogen fuel cells and supercapacitors scheme. This is the world fastest FСНPP limited at 160 km/h. Using hydrogen, the train is expected to reduce CO2 emissions by 10 tons per year compared to diesel. China still operates 7,800 locomotives with internal combustion engines, accounting for 36% of the total number of locomotives in the country. This is not the first hydrogen rolling stock by CRRC. The company presented a shunting locomotive (800 kWt) in 2021, and hydrogen trams in the mid-2010s. Signed the first export agreement for supply of a hydrogen locomotive to Chile.
FV-E991系, nicknamed HYBARI – two-car railway vehicles equipped with hybrid systems that use PEMFC and storage batteries as their source of electricity started trial period at East Japan Railway Company (JR East), the largest railway company in Japan in February 2022. Toyota is developing the fuel cell device and Hitachi is developing the hybrid drive system. The train is equipped with four units of five hydrogen tanks each with a capacity of 72 kg at a pressure of 700 bar. Hybari costs about $35 million and can autonomously drive 140 km with a top speed of 110 km/h. JR East plans to begin commercial service using the locomotive starting in 2030. The company plans to gradually reduce its entire 440 diesel locomotive fleet.
FC H2 RAIL is a consortium of CAF, DLR, Toyota, Renfe, ADIF, CNH2, IP and Stemmann-Technik around demonstrator train, a Renfe’s “Civia” three-car commuter unit, has run in November 2023 on the Zaragoza-Canfranc line in Spain both in electric mode, in the electrified area, and in hybrid mode, combining energy from PEMFC and batteries in the non-electrified sections. The project should result in the development of a modular FCHPP fit for use in different vehicles, such as multiple unit, mainline and shunting locomotives. The second generation fuel cell systems from Toyota Motor Europe reformed for installation on the train’s roof. The project has a €14-million budget, €10 million of which is being funded by the Clean Hydrogen Partnership, formerly FCH2 JU, a European Commission agency dedicated to promoting the development of hydrogen and fuel cells.
K-Train – Korean rolling stock maker Woojin Industrial Systems Co. and the state-run train service provider Korea Railroad Corp. started developing the hydrogen program in 2018. The electric two-car ITX-Saemaeul unit is equipped with PEMFC (200 kWt) and also features a smart energy management system. The train is equipped with 14 cylinders of 83 kg H2 each pressurized to 700 barr. It has a maximum operational speed of more than 110 km/h and a range of more than 600 km on a single charge. The capacity is 132 pax. Project cost $19.2 million, state funding $17 million. Only modest data about the current status of the project is available. According to reports in the Korean press, the project has budget problems, and the train has not been operated much this year. Last year, Woojin was convicted by a court of collusion and paid a multimillion-dollar fine.
There are several other passenger train projects, all in the developing or testing phases, there is no point in recounting the details, no full data, there are four such projects in India alone. Hydrogen-powered traction and shunting locomotives deserve a separate study. Technical and economic specifics of the freight transportation sector do not allow combining it logically with data on passenger trains. So far, only CRRC has the one certified shunting locomotive.
In general, it can be testified that decarbonization of the transport industry through the railway sector is the most successful solution in terms of cost and effect. There are about 70,000 diesel locomotives in the world. Converting routes to electric traction will not only give a direct reduction in CO2 emissions by about 700 thousand tons of Scope 1, but will also reduce the demand for diesel, which has a carbon footprint of 2..7 mT CO2/t.
Blue Carriage
The Blue Carriage project, developed in Russia, stands apart.The project involved placing inside a four-axle gondola car of a specialized model 12-6993 (extended base 18.5 meters) a liquid hydrogen tank equipped with an evaporator and heat exchange equipment, including an electric heater required for the launch period, a fuel cell with a power of up to 720 kW and auxiliary electrical equipment.
The purpose of the “Blue Carriage” was to generate and supply electricity to the locomotive in front, which has an electric drive.The cruising range for the train with the Blue Carriage was provided by the tank volume for approximately 1 ton of liquid hydrogen and reached 1200 km without additional equipment.The car was intended for the rapid implementation of ESG principles in enterprises with a large number of diesel locomotives operating on internal tracks.
Unfortunately, the project was never fully implemented due to political events that led to the collapse of the engineering team
TGM4-H
Spanish company Coolergy S.L. has started the project of retrofitting of 12 shunting locomotives operating in Riga Port. All locomotives are represented by one model TGM4 – a shunting locomotive with a hydraulic drive. Historically, the railway network built in the port of Riga does not allow the use of extended models, which makes the selection of suitable machines problematic.
The parameters of TGM4 meet all the nuances of the track being serviced.It is expected that the locomotives will be equipped with fuel cells and batteries, providing a total of up to 500 kW of power.
Liquid hydrogen will be stored in replaceable tank containers installed on the locomotive platform.The tank containers are supposed to be refueled directly at the hydrogen production and liquefaction plant, which will be built within a year in Liepaja, and be powered by electricity from the local wind farm.
This refueling principle makes it possible to eliminate hydrogen losses when equipping locomotives on site, since at the hydrogen plant itself it is possible to provide complete precooling with the generated hydrogen, which is returned to the beginning of the cycle through these tank containers.
The tank volume is designed for weekly consumption of approximately 500 kilograms of hydrogen.To supply the locomotive fleet with hydrogen, Coolergy will build a modular integrated hydrogen production and liquefaction plant with a capacity of 1 ton per day within a year. surplus hydrogen will be used to develop other types of ground transport, which Coolergy is developing together with its partners.
Author – Serge Astafurov