Hydrogen Vehicle
Overview
A hydrogen vehicle is an eco-friendly vehicle that uses hydrogen as fuel to produce electricity, which then drives a motor to move. Unlike internal combustion engine vehicles, it emits only water (H₂O) as exhaust, making it a key means of reducing air pollution and greenhouse gases. Hydrogen vehicles are broadly divided into hydrogen fuel cell electric vehicles (FCEV) and hydrogen internal combustion engine vehicles (HICEV), with most currently commercialized models being FCEVs.
Main Content
Operating Principle
The core of a hydrogen vehicle is the fuel cell stack. Inside the fuel cell stack, hydrogen (H₂) is split into hydrogen ions (H⁺) and electrons (e⁻) by a catalyst (mainly platinum) at the anode. The hydrogen ions move through the electrolyte membrane to the cathode, while the electrons flow through an external circuit, generating electricity. At the cathode, oxygen (O₂) from the air combines with the hydrogen ions and electrons to produce water. This electricity drives the motor, and the generated water is emitted as steam through the exhaust pipe.
Key Components
- Fuel Cell Stack: The core component where the electrochemical reaction of hydrogen and oxygen occurs. Multiple cells are stacked to achieve the required voltage and output.
- Hydrogen Storage Tank: A composite material tank that stores hydrogen at high pressure (700 bar). It is designed with crash safety in mind.
- Power Conversion Device: Converts the direct current (DC) electricity produced by the fuel cell into alternating current (AC) suitable for driving the motor or for charging the battery.
- High-Voltage Battery: Assists the fuel cell's output and stores regenerative braking energy. It operates similarly to a hybrid system.
- Electric Motor: Converts electrical energy into mechanical energy to drive the wheels.
Advantages
- Eco-Friendliness: Emits no harmful substances such as carbon dioxide, nitrogen oxides, or fine particulate matter during driving. If renewable energy is used in the hydrogen production process, Well-to-Wheel (from raw material to wheel) carbon emissions are virtually zero.
- Refueling Time: Compared to the slow charging of battery electric vehicles (BEVs, which takes several hours), hydrogen refueling takes only about 3 to 5 minutes, similar to the refueling experience of internal combustion engine vehicles.
- Driving Range: Can travel 600 to 800 km (based on the Hyundai Nexo) on a single charge, advantageous for long-distance driving.
- Cold Weather Performance: While BEVs experience reduced driving range in winter, hydrogen vehicles maintain relatively consistent performance by utilizing the heat generated by the fuel cell.
Disadvantages and Challenges
- Lack of Infrastructure: As of 2024, there are only about 1,000 hydrogen refueling stations worldwide. South Korea has a relatively high number with around 200, but they are still concentrated in the capital area and some major cities.
- High Production Costs: The use of precious metal catalysts like platinum in the fuel cell and the high manufacturing cost of high-pressure tanks make the vehicle expensive (e.g., the Hyundai Nexo costs around 70 million KRW).
- Environmental Impact of Hydrogen Production: Currently, most hydrogen is produced through steam methane reforming, which generates carbon dioxide. The production of 'green hydrogen' (via water electrolysis using renewable electricity) is still costly and small in scale.
- Hydrogen Storage and Transport: Hydrogen has a low energy density per volume, requiring high-pressure liquefaction or compression, which consumes significant energy for storage and transport.
- Safety Perception: Public concerns exist about hydrogen's flammability and explosion risk, but in reality, thorough safety designs (hydrogen leak detection, automatic shut-off valves, crash-safe tanks) result in a very low accident rate.
Major Models and Manufacturers
- Hyundai Motor Company: Tucson ix35 Fuel Cell (2013), Nexo (2018–present) is the world's first mass-produced FCEV SUV. A new model equipped with a 3rd-generation fuel cell system is scheduled for release in 2025.
- Toyota: Mirai (2014–present) is a sedan-type FCEV. The 2nd generation (2020) achieved a driving range of 850 km (Japan standard).
- Honda: Produced the Clarity Fuel Cell (2016–2021), but discontinued it in 2021. A next-generation FCEV system is under development as of 2024.
- BMW: Small-scale pilot production of the iX5 Hydrogen (2023). Also researching hydrogen internal combustion engine vehicles.
- Stellantis: Launched commercial vans (Peugeot e-Expert Hydrogen, Citroën ë-Jumpy Hydrogen).
Government Policies and Support
- South Korea: Through the 'Hydro Economy Activation Roadmap' (2019) and the 'Act on the Promotion of Hydrogen Economy and Hydrogen Safety Management' (2021), subsidies for hydrogen vehicles (approx. 32.5 million KRW as of 2024), support for refueling station construction, and investment in hydrogen production infrastructure are underway. Targets include 850,000 hydrogen vehicles and 660 refueling stations by 2030.
- Japan: The 'Basic Hydrogen Strategy' (revised 2023) aims for a hydrogen supply of 3 million tons by 2030 and 12 million tons by 2040. Led by private companies like Toyota and Honda.
- European Union: The 'REPowerEU' plan (2022) targets the production of 10 million tons of renewable hydrogen by 2030. Germany, France, the Netherlands, etc., are expanding their refueling station networks.
- United States: The IRA (Inflation Reduction Act, 2022) provides tax credits (up to $3 per kg) for green hydrogen production. Hydrogen vehicle deployment is centered in California.
Latest Trends
As of 2024–2025, the hydrogen vehicle market appears relatively stagnant compared to the rapid growth of battery electric vehicles (BEVs). Global FCEV sales decreased from about 14,000 units in 2023 to less than 10,000 units in 2024. The main reasons are the lack of refueling infrastructure and rising hydrogen prices (8,000–10,000 KRW per kg in South Korea, making the cost per driving distance higher than BEVs).
However, technological progress continues. Hyundai Motor Company expanded its hydrogen fuel cell system to commercial vehicles, ships, and drones under the 'HTWO' brand in 2024, and announced a 3rd-generation fuel cell (30% improvement in power density, 50% cost reduction) in 2025. Toyota accelerated its 'hydrogen engine' project in 2024, applying the Mirai's fuel cell system to large trucks and buses.
Additionally, the transition in hydrogen production methods has emerged as a key challenge. The cost of green hydrogen production is expected to drop from $5–6 per kg in 2020 to $2–3 per kg by 2025, with increasing investment in large-scale water electrolysis facilities (alkaline, PEM, solid oxide). South Korea introduced a 'Clean Hydrogen Certification System' in 2024, providing differentiated support for green hydrogen and blue hydrogen (with CCUS).
The role of hydrogen in the commercial vehicle sector is being re-evaluated. Suitable for long-distance, heavy-load transport such as large trucks, buses, and forklifts, pilot operations of hydrogen trucks expanded in Germany, China, and South Korea in 2024. Hyundai Motor Company plans to launch the 'Xcient Hydrogen Electric Truck' in Europe in 2025.
Regarding safety, following a hydrogen refueling station explosion accident in South Korea (2023), strengthened safety standards have been applied in 2024, with hydrogen leak detection sensors and automatic shut-off systems becoming standardized.
Related Topics
- [[Fuel Cell]]
- [[Electric Vehicle]]
- [[Hydrogen Economy]]
- [[Green Hydrogen]]
- [[Carbon Neutrality]]