A fuel cell is an electrochemical cell that converts the chemical energy of a fuel and an oxidizing agent into electricity through a pair of redox reactions. Fuel cells are different from most batteries in requiring a continuous source of fuel and oxygen to sustain the chemical reaction, whereas in a battery the chemical energy usually comes from substances that are already present in the battery. Fuel cells can produce electricity continuously for as long as fuel and oxygen are supplied.
Liquid hydrogen (H2(l)) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.
Fuel efficiency is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile. Non-transportation applications, such as industry, benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion, such as ammonia production during the Haber process.
Aviation fuels are petroleum-based fuels, or petroleum and synthetic fuel blends, used to power aircraft. They have more stringent requirements than fuels used for ground use, such as heating and road transport, and contain additives to enhance or maintain properties important to fuel performance or handling. They are kerosene-based for gas turbine-powered aircraft. Piston-engined aircraft use leaded gasoline and those with diesel engines may use jet fuel (kerosene). By 2012, all aircraft operated by the U.S. Air Force had been certified to use a 50-50 blend of kerosene and synthetic fuel derived from coal or natural gas as a way of stabilizing the cost of fuel.
The hydrogen economy uses hydrogen to decarbonize economic sectors which are hard to electrify, essentially, the "hard-to-abate" sectors such as cement, steel, long-haul transport, etc. In order to phase out fossil fuels and limit climate change, hydrogen can be created from water using renewable sources such as wind and solar, and its combustion only releases water vapor into the atmosphere.
Hydrogen fuel refers to hydrogen which is burned as fuel with oxygen. It can be a zero-carbon fuel, provided that it is created in a process that does not involve carbon. There are many types of hydrogen like white, green, blue, grey, black, or brown hydrogen owing to the various methods of processes by which they come. It can be used in fuel cells or internal combustion engines. Regarding hydrogen vehicles, hydrogen has begun to be used in commercial fuel cell vehicles such as passenger cars, and has been used in fuel cell buses for many years. It is also used as a fuel for spacecraft propulsion and is being proposed for hydrogen-powered aircraft. The fuel technology has seen awakened interest from automakers who claim it is comparatively cheap and safer to incorporate into the modern vehicle architecture over recent challenges faced by electric vehicle makers.
A fuel cell vehicle (FCV) or fuel cell electric vehicle (FCEV) is an electric vehicle that uses a fuel cell, sometimes in combination with a small battery or supercapacitor, to power its onboard electric motor. Fuel cells in vehicles generate electricity generally using oxygen from the air and compressed hydrogen. Most fuel cell vehicles are classified as zero-emissions vehicles that emit only water and heat. As compared with internal combustion vehicles, hydrogen vehicles centralize pollutants at the site of the hydrogen production, where hydrogen is typically derived from reformed natural gas. Transporting and storing hydrogen may also create pollutants. Fuel cells have been used in various kinds of vehicles including forklifts, especially in indoor applications where their clean emissions are important to air quality, and in space applications. Fuel cells are being developed and tested in trucks, buses, boats, ships, motorcycles and bicycles, among other kinds of vehicles.
The Sabatier reaction or Sabatier process produces methane and water from a reaction of hydrogen with carbon dioxide at elevated temperatures and pressures in the presence of a nickel catalyst. It was discovered by the French chemists Paul Sabatier and Jean-Baptiste Senderens in 1897. Optionally, ruthenium on alumina makes a more efficient catalyst. It is described by the following exothermic reaction:
A fossil fuel power station is a thermal power station which burns a fossil fuel, such as coal or natural gas, to produce electricity. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator. The prime mover may be a steam turbine, a gas turbine or, in small plants, a reciprocating gas engine. All plants use the energy extracted from the expansion of a hot gas, either steam or combustion gases. Although different energy conversion methods exist, all thermal power station conversion methods have their efficiency limited by the Carnot efficiency and therefore produce waste heat.
In physics, energy density is the amount of energy stored in a given system or region of space per unit volume. It is sometimes confused with energy per unit mass which is properly called specific energy or gravimetric energy density.
The methanol economy is a suggested future economy in which methanol and dimethyl ether replace fossil fuels as a means of energy storage, ground transportation fuel, and raw material for synthetic hydrocarbons and their products. It offers an alternative to the proposed hydrogen economy or ethanol economy, though these concepts are not exclusive.
A hydrogen station is a storage or filling station for hydrogen fuel. The hydrogen is dispensed by weight. There are two filling pressures in common use: H70 or 700 bar, and the older standard H35 or 350 bar. As of 2021, around 550 filling stations were available worldwide.
Electrolysis of water is using electricity to split water into oxygen and hydrogen gas by electrolysis. Hydrogen gas released in this way can be used as hydrogen fuel, or remixed with the oxygen to create oxyhydrogen gas, for use in welding and other applications.
The H-Prize program is a series of inducement prizes intended to encourage research into the use of hydrogen as an energy carrier in a hydrogen economy. The program is sponsored by the United States Department of Energy and administered by the Hydrogen Education Foundation. In 2014, an H-Prize competition was launched to develop a small-scale hydrogen generation and refueling station for hydrogen fuel cell electric vehicles. The prize, named the H2 Refuel H-Prize and worth $1 million, was awarded in January 2017, to the consortium "SimpleFuel".
Hydrogen production is the family of industrial methods for generating hydrogen gas. As of 2020, the majority of hydrogen (~95%) is produced from fossil fuels by steam reforming of natural gas and other light hydrocarbons, partial oxidation of heavier hydrocarbons, and coal gasification. Other methods of hydrogen production include biomass gasification, methane pyrolysis, and electrolysis of water. Methane pyrolysis and water electrolysis can use any source of electricity including solar power.
Hydrogen technologies are technologies that relate to the production and use of hydrogen as a part hydrogen economy. Hydrogen technologies are applicable for many uses.
A nickel–hydrogen battery (NiH2 or Ni–H2) is a rechargeable electrochemical power source based on nickel and hydrogen. It differs from a nickel–metal hydride (NiMH) battery by the use of hydrogen in gaseous form, stored in a pressurized cell at up to 1200 psi (82.7 bar) pressure. The nickel–hydrogen battery was patented on February 25, 1971 by Alexandr Ilich Kloss and Boris Ioselevich Tsenter in the United States.
Tallawarra Power Station is a 435-megawatt (583,000 hp) combined cycle natural gas power station in the city of Wollongong, New South Wales, Australia. Owned and operated by EnergyAustralia, the station is the first of its type in New South Wales and produces electricity for the state during periods of high demand. It is located on the western shore of Lake Illawarra in the suburb of Yallah.
The Honda FCX is a family of hydrogen fuel cell automobiles manufactured by Honda.
The Toyota Mirai is a mid-size hydrogen fuel cell vehicle (FCV) manufactured by Toyota, and is the first FCV automobiles to be mass-produced and sold commercially. The Mirai was unveiled at the November 2014 Los Angeles Auto Show. As of November 2022, global sales totaled 21,475 units; the top-selling markets were the U.S. with 11,368 units, Japan with 7,435 and the rest of the world with 2,622.