Hydrogen vehicle
A hydrogen vehicle is a vehicle that uses hydrogen to move. Hydrogen vehicles include some road vehicles, rail vehicles, space rockets, forklifts, ships and aircraft. Motive power is generated by converting the chemical energy of hydrogen to mechanical energy, either by reacting hydrogen with oxygen in a fuel cell to power electric motors or, less commonly, by hydrogen internal combustion.
Hydrogen burns cleaner than fuels such as gasoline or methane but is more difficult to store and transport because of the small size of the molecule. As of the 2020s hydrogen light duty vehicles, including passenger cars, have been sold in small numbers due to competition with battery electric vehicles., there were two models of hydrogen cars publicly available in select markets: the Toyota Mirai, the first commercially produced dedicated fuel cell electric vehicle, and the Hyundai Nexo. The Honda CR-V e:FCEV became available, for lease only, in very limited quantities in 2024.
As of 2019, 98% of hydrogen is produced by steam methane reforming, which emits carbon dioxide. It can be produced by electrolysis of water, or by thermochemical or pyrolytic means using renewable feedstocks, but the processes are currently expensive. Various technologies are being developed that aim to deliver costs low enough, and quantities great enough, to compete with hydrogen production using natural gas.
Vehicles running on hydrogen technology benefit from a long range on a single refuelling, but are subject to several drawbacks including high carbon emissions when hydrogen is produced from natural gas, capital cost burden, high energy inputs in production and transportation, low energy content per unit volume at ambient conditions, production and compression of hydrogen, and the investment required to build refuelling infrastructure around the world to dispense hydrogen. In addition, leaked hydrogen is an invisible, highly flammable gas and has a global warming effect 11.6 times stronger than CO2.
Vehicles
Rationale and context
The rationale for hydrogen vehicles lies in their potential to reduce reliance on fossil fuels, associated greenhouse gas emissions and localised air pollution from transportation. This would require hydrogen to be produced cleanly, for use in sectors and applications where cheaper and more energy efficient mitigation alternatives are limited.Rockets
Many large rockets use liquid hydrogen as fuel, with liquid oxygen as an oxidizer. An advantage of hydrogen rocket fuel is the high effective exhaust velocity compared to kerosene/LOX or UDMH/NTO engines. According to the Tsiolkovsky rocket equation, a rocket with higher exhaust velocity uses less propellant to accelerate. Also the energy density of hydrogen is greater than any other fuel. LH2/LOX also yields the greatest efficiency in relation to the amount of propellant consumed, of any known rocket propellant.A disadvantage of LH2/LOX engines is the low density and low cryogenic temperature required to maintain of hydrogen as a liquid, which means bigger and insulated and thus heavier fuel tanks are needed compared to methane, although methane is more polluting. Another disadvantage is the poor storability of LH2/LOX-powered rockets: Due to the constant hydrogen boil-off, the rocket must be fueled shortly before launch, which makes cryogenic engines unsuitable for ICBMs and other rocket applications with the need for short launch preparations. For first stages, dense fuelled rockets in studies may show a small advantage, due to the smaller vehicle size and lower air drag.
LH2/LOX were also used in the Space Shuttle to run the fuel cells that power the electrical systems. The byproduct of the fuel cell is water, which is used for drinking and other applications that require water in space.
Automobiles
, there were two hydrogen cars publicly available in select markets: the Toyota Mirai and the Hyundai Nexo. The Honda Clarity was produced from 2016 to 2021. Hydrogen combustion cars are not commercially available. In the light road vehicle segment, by the end of 2022, 70,200 fuel cell electric vehicles had been sold worldwide, compared with 26 million plug-in electric vehicles. In 2023, 3,143 hydrogen cars were sold in the US compared with 380,000 battery electric vehicles. With the rapid rise of electric vehicles and associated battery technology and infrastructure, the global scope for hydrogen's role in cars is shrinking relative to earlier expectations. John Max of Hydrogen Fuel News believes that hydrogen may, however, be used directly, or as a feedstock for efuel, to keep classic cars on the road.The first road vehicle powered by a hydrogen fuel cell was the Chevrolet Electrovan, introduced by General Motors in 1966. The Toyota FCHV and Honda FCX, which began leasing on December 2, 2002, became the world's first government-certified commercial hydrogen fuel cell vehicles, and the Honda FCX Clarity, which began leasing in 2008, was the world's first hydrogen fuel cell vehicle designed for mass production rather than adapting an existing model. Honda established the world's first fuel cell vehicle dealer network in 2008, and at the time was the only company able to lease hydrogen fuel cell vehicles to private customers.
The 2013 Hyundai Tucson FCEV, a modified Tucson, was introduced to the market as a lease-only vehicle, and Hyundai Motors claimed it was the world's first mass-produced hydrogen fuel cell vehicle. However, due to high prices and a lack of charging infrastructure, sales fell far short of initial plans, with only 273 units sold by the end of May 2015. Hyundai Nexo, which succeeded the Tucson in 2018, was selected as the "safest SUV" by the Euro NCAP in 2018, but In October 2024, Hyundai recalled all 1,600 Nexo vehicles sold in the US to that time due to a risk of fuel leaks and fire from a faulty "pressure relief device".
Toyota launched the world's first dedicated mass-produced fuel cell vehicle, the Mirai, in Japan at the end of 2014 and began sales in California, mainly the Los Angeles area and also in selected markets in Europe, the UK, Germany and Denmark later in 2015. The car has a range of and takes about five minutes to refill its hydrogen tank. The initial sale price in Japan was about 7 million yen. Former European Parliament President Pat Cox estimated that Toyota would initially lose about $100,000 on each Mirai sold. At the end of 2019, Toyota had sold over 10,000 Mirais, but in 2024, Toyota's worldwide sales fell to 1,702 hydrogen fuel cell vehicles. Many automobile companies introduced demonstration models in limited numbers.
In 2013 BMW leased hydrogen technology from Toyota, and a group formed by Ford Motor Company, Daimler AG, and Nissan announced a collaboration on hydrogen technology development. In 2015, Toyota announced that it would offer all 5,680 patents related to hydrogen fuel cell vehicles and hydrogen fuel cell charging station technology, which it has been researching for over 20 years, to its competitors free of charge to stimulate the market for hydrogen-powered vehicles. By 2017, however, Daimler had abandoned hydrogen vehicle development, and most of the automobile companies developing hydrogen cars had switched their focus to battery electric vehicles. By 2020, all but three automobile companies had abandoned plans to manufacture hydrogen cars. The Honda CR-V e:FCEV became available, for lease only, in very limited quantities in 2024.
A significant number of the public hydrogen fuel stations in the California are not able to dispense hydrogen. In 2024, Mirai owners filed a class action lawsuit in California over the lack of availability of hydrogen available for fuel cell electric cars, alleging, among other things, fraudulent concealment and misrepresentation as well as violations of California’s false advertising law and breaches of implied warranty.
Heavy trucks
The International Energy Agency's 2022 net-zero emissions scenario sees hydrogen meeting approximately 30% of heavy truck energy demand in 2050, mainly for long-distance heavy freight.United Parcel Service began testing of a hydrogen powered delivery vehicle in 2017. In 2020, Hyundai began commercial production of its Xcient fuel cell trucks and shipped ten of them to Switzerland.
In 2022 in Australia, five hydrogen fuel cell class 8 trucks were placed into use to transport zinc from Sun Metals' Townsville mine to the Port of Townsville, Queensland, to be shipped around the world.
Aeroplanes
Some publications project hydrogen may be used in shipping and jetplanes, while others predict that biofuels and batteries will have more commercial success. Companies such as Boeing, Lange Aviation, and the German Aerospace Center are pursuing hydrogen as fuel for crewed and uncrewed aeroplanes. In February 2008 Boeing tested a crewed flight of a small aircraft powered by a hydrogen fuel cell. Uncrewed hydrogen planes have also been tested. For large passenger aeroplanes, The Times reported that "Boeing said that hydrogen fuel cells were unlikely to power the engines of large passenger jet aeroplanes but could be used as backup or auxiliary power units onboard."In July 2010, Boeing unveiled its hydrogen-powered Phantom Eye UAV, powered by two Ford internal-combustion engines that have been converted to run on hydrogen.
Ships
hydrogen fuel cells are not suitable for propulsion in large long-distance ships but are being considered as a range-extender for smaller, short-distance, low-speed electric vessels, such as ferries. Hydrogen in ammonia is being considered as a long-distance fuel.Buses
Fuel-cell buses were trialed in Ursus Lublin in 2017. Solaris Bus & Coach introduced its Urbino 12 hydrogen electric buses in 2019. Several dozen were ordered. The first city in the U.S. to have a fleet of hydrogen powered buses was Champaign, Illinois, when in 2021 the Champaign–Urbana Mass Transit District ordered two New Flyer XHE60 articulated hydrogen fuel cell buses, with 10 more New Flyer XHE40 buses added in 2024.In 2022, the city of Montpellier, France, cancelled a contract to procure 51 buses powered by hydrogen fuel cells, when it found that "the cost of operation for hydrogen is 6 times the cost of electricity". By 2025, most hydrogen bus programs in Europe had been cancelled or fuel cell bus purchases discontinued.