A hydrogen economy is a hypothetical economy in which the energy needed for motive power (for automobiles and other vehicle types) or electricity (for stationary applications) is derived from reacting hydrogen (H2) with oxygen. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός Vehicles, derived from the Latin word vehiculum, are non-living Means of transport. Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 While the primary purpose is to eliminate the use of carbon-based fossil fuels and thus reduce carbon dioxide emissions, a secondary goal is to provide an energy carrier to replace dwindling supplies of petroleum as well as to provide energy independence to countries without oil resources. Fossil fuels or mineral fuels are fossil source Fuels that is Hydrocarbons found within the top layer of the Earth’s crust. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Access to cheap energy has become essential to the functioning of modern economies
In the context of a hydrogen economy, hydrogen is an energy storage medium, not a primary energy source (see nuclear fusion for an entirely separate discussion of using hydrogen isotopes as an atomic energy source). In Physics and Nuclear chemistry, nuclear fusion is the process by which multiple- like charged atomic nuclei join together to form a heavier nucleus Nevertheless, controversy over the usefulness of a hydrogen economy have been confused by issues of energy sourcing, including fossil fuel use, global warming, and sustainable energy generation. Fossil fuels or mineral fuels are fossil source Fuels that is Hydrocarbons found within the top layer of the Earth’s crust. Global warming is the increase in the average measured temperature of the Sustainable energy is the provision of energy such that it meets the needs of the present without compromising the ability of future generations to meet their needs These are all separate issues, although the hydrogen economy affects them all (see below).
Proponents of a hydrogen economy suggest that hydrogen is an environmentally cleaner source of energy to end-users, particularly in transportation applications, without release of pollutants (such as particulate matter) or greenhouse gases at the point of end use. Analyses have concluded that "most of the hydrogen supply chain pathways would release significantly less carbon dioxide into the atmosphere than would gasoline used in hybrid electric vehicles" and that significant reductions in carbon dioxide emissions would be possible if carbon capture or carbon sequestration methods are utilized at the site of energy or hydrogen production. A plug-in hybrid electric vehicle ( PHEV) is a Hybrid vehicle with batteries that can be recharged by connecting a plug to an Electric power Carbon capture and storage ( CCS) is an approach to mitigating Global warming based on capturing Carbon dioxide (CO2 from large 
Critics of a hydrogen economy argue that for many planned applications of hydrogen, direct distribution and use of energy in the form of electricity, or alternate means of storage such as chemical batteries, fuel plus fuel cells, or production of liquid synthetic fuels from CO2 (see methanol economy), might accomplish many of the same net goals of a hydrogen economy, while requiring only a small fraction of the investment in new infrastructure. A fuel cell is an electrochemical conversion device It produces electricity from Fuel (on the Anode side and an oxidant (on the Synthetic fuel or synfuel is any Liquid fuel obtained from Coal, Natural gas, or Biomass. The methanol economy is a suggested future Economy in which Methanol replaces Fossil fuels as a mean of energy storage fuel and raw material for synthetic  Hydrogen has been called the least efficient and most expensive possible replacement for gasoline (petrol).  A comprehensive study of hydrogen in transportation applications has found that "there are major hurdles on the path to achieving the vision of the hydrogen economy; the path will not be simple or straightforward". 
A hydrogen economy is proposed to solve the ill effects of using hydrocarbon fuels in transportation, and other end-use applications where the carbon is released to the atmosphere. In Organic chemistry, a hydrocarbon is an Organic compound consisting entirely of Hydrogen and Carbon.
In the current hydrocarbon economy, the transportation of people and goods (so-called mobile applications) is fueled primarily by petroleum, refined into gasoline and diesel, and natural gas. Hydrocarbon economy is a term stressing that in the current world economy the energy used mostly comes from three Hydrocarbons Petroleum, Coal Transport or transportation is the movement of people and goods from one place to another Fuel is any material that is burned or altered in order to obtain energy Petroleum ( L petroleum, from Greek πετρέλαιον, lit Diesel or Diesel fuel (ˈdiːzəl in general is any Fuel used in Diesel engines The most common is a specific fractional distillate of petroleum Natural gas is a Gaseous Fossil fuel consisting primarily of Methane but including significant quantities of Ethane, Propane, However, the burning of these hydrocarbon fuels causes the emission of greenhouse gases and other pollutants. In Organic chemistry, a hydrocarbon is an Organic compound consisting entirely of Hydrogen and Carbon. Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared Pollution is the introduction of contaminants into an environment that causes instability disorder harm or discomfort to the physical systems or living organisms they are in Furthermore, the supply of hydrocarbon resources in the world is limited, and the demand for hydrocarbon fuels is increasing, particularly in China, India and other developing countries. Talk People's Republic of China) PEOPLE'S REPUBLIC OF CHINA ARTICLE GUIDELINES India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country
Hydrogen has a high energy density by weight. Energy density is the amount of Energy stored in a given system or region of space per unit Volume, or per unit Mass, depending on the context although Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object The fuel cell is also more efficient than an internal combustion engine. The internal combustion engine is said to be 20–30% efficient, while the fuel cell is 35–45% efficient (some even higher) (not accounting for losses in the actual production of hydrogen, which would result in an overall efficiency of about 25%) and together with the electric motor and controller, the drive train overall efficiency approaches 24% with low idling losses. 
Hydrogen production is a large and growing industry. Globally, some 50 million metric tons of hydrogen, equal to about 170 million tons of oil equivalent, were produced in 2004. This article is about the tonne or metric ton For other tons see Ton. The tonne of oil equivalent ( toe) is a unit of energy: the amount of energy released by burning one Tonne of Crude oil, approximately 42 The growth rate is around 10% per year. Within the United States, 2004 production was about 11 million metric tons (MMT), an average power flow of 48 gigawatts. The United States of America —commonly referred to as the (For comparison, the average electric production in 2003 was some 442 gigawatts. ) As of 2005, the economic value of all hydrogen produced worldwide is about $135 billion per year. 
There are two primary uses for hydrogen today. About half is used to produce ammonia (NH3) via the Haber process, which is then used directly or indirectly as fertilizer. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 The Haber process, also called the Haber–Bosch process, is the Nitrogen fixation reaction of Nitrogen and Hydrogen, over an iron substrate Fertilizers ( also spelt fertiliser are chemical compounds given to Plants to promote growth they are usually applied either through the soil for uptake by plant Because both the world population and the intensive agriculture used to support it are growing, ammonia demand is growing. The world population is the total number of living Humans on Earth at a given time Agriculture refers to the production of goods through the growing of plants and fungi and the raising of domesticated Animals The study of agriculture The other half of current hydrogen production is used to convert heavy petroleum sources into lighter fractions suitable for use as fuels. Petroleum ( L petroleum, from Greek πετρέλαιον, lit In Mathematics, a fraction (from the Latin fractus, broken is a concept of a proportional relation between an object part and the object This latter process is known as hydrocracking. In Petroleum geology and Chemistry, cracking is the process whereby complex organic Molecules such as Kerogens or heavy Hydrocarbons Hydrocracking represents an even larger growth area, since rising oil prices encourage oil companies to extract poorer source material, such as tar sands and oil shale. The scale economies inherent in large scale oil refining and fertilizer manufacture make possible on-site production and "captive" use. Smaller quantities of "merchant" hydrogen are manufactured and delivered to end users as well.
If energy for hydrogen production were available (from wind, solar or nuclear power), use of the substance for hydrocarbon synfuel production could expand captive use of hydrogen by a factor of 5 to 10. Present U. S. use of hydrogen for hydrocracking is roughly 4 million metric tons per year (4 MMT/yr). It is estimated that 37. 7 MMT/yr of hydrogen would be sufficient to convert enough domestic coal to liquid fuels to end U. S. dependence on foreign oil importation, and less than half this figure to end dependence on Middle East oil. Coal liquefaction would present significantly worse emissions of carbon dioxide than does the current system of burning fossil petroleum, but it would eliminate the political and economic vulnerabilities inherent in oil importation.
Currently, global hydrogen production is 48% from natural gas, 30% from oil, and 18% from coal; water electrolysis accounts for only 4%. Natural gas is a Gaseous Fossil fuel consisting primarily of Methane but including significant quantities of Ethane, Propane, Petroleum ( L petroleum, from Greek πετρέλαιον, lit In chemistry and manufacturing electrolysis is a method of separating chemically bonded elements and compounds by passing an Electric current  The distribution of production reflects the effects of thermodynamic constraints on economic choices: of the four methods for obtaining hydrogen, partial combustion of natural gas in a NGCC (natural gas combined cycle) power plant offers the most efficient chemical pathway and the greatest off-take of usable heat energy. A combined cycle is characteristic of a power producing engine or plant that employs more than one Thermodynamic cycle.
The large market and sharply rising prices in fossil fuels have also stimulated great interest in alternate, cheaper means of hydrogen production. 
Today hydrogen is produced for merchant use and captive industrial applications using mature, thermodynamically efficient technologies. See also Timeline of hydrogen technologies Hydrogen technologies are technologies that relate to the production and use of hydrogen Linking its centralized production to a fleet of light-duty fuel cell vehicles will require the siting and construction of a distribution infrastructure with large investment of capital. A hydrogen vehicle is a Vehicle that uses Hydrogen as its on-board fuel for motive power Further, the technological challenge of providing safe, energy-dense storage of hydrogen on-board the vehicle must be overcome to provide sufficient range between fillups.
Molecular hydrogen is not available on Earth in convenient natural reservoirs, though it is an atmospheric trace gas having a mixing ratio of 500 parts per billion by volume in addition to being produced by microbes and consumed by methanogens in a rapid biological hydrogen cycle. Hydrogen is commonly produced by extraction from Hydrocarbon Fossil fuels via a chemical path Humidity is the amount of water vapor in the air In daily language the term "humidity" is normally taken to mean Relative humidity. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually Methanogens are Archaea that produce Methane as a Metabolic byproduct in Anoxic conditions Most hydrogen on Earth is bonded to oxygen in water. Hydrogen is presently most economically produced using fossil fuels. In practice this is usually methane, though hydrogen can also be produced via steam reforming or partial oxidation of coal. More expensively it can also be produced via electrolysis using electricity and water, consuming approximately 50 kilowatt-hours of electricity per kilogram of hydrogen produced. In chemistry and manufacturing electrolysis is a method of separating chemically bonded elements and compounds by passing an Electric current Though the use of platinum as a catalyst for electrolytic separation of H2O into hydrogen and oxygen is well-known, the actual amount of known or projected platinum in Earth would allow for less than a hundredth of a cubic centimeter for every one out of three people on Earth for private use or ownership. Nuclear power can provide the energy for hydrogen production by a variety of means, but its widescale deployment is opposed in some Western economies while it is embraced in others. Renewable energy is being used to produce hydrogen in Denmark and Iceland. Renewable energy is Energy generated from Natural resources mdashsuch as Sunlight, Wind, Rain, tides and geothermal 
The environmental effects of hydrogen production can be compared with alternatives, taking into account not only the emissions and efficiency of the hydrogen production process but also the efficiency of the hydrogen conversion to electricity in a fuel cell.
While hydrogen (the element) is abundant on Earth, and indeed is the most abundant element in the universe, manufacturing hydrogen does require the consumption of a hydrogen carrier such as a fossil fuel or water. Fossil fuels or mineral fuels are fossil source Fuels that is Hydrocarbons found within the top layer of the Earth’s crust. The former consumes the fossil resource and produces carbon dioxide, but often requires no further energy input beyond the fossil fuel. Decomposing water requires electrical or heat input, generated from some primary energy source (fossil fuel, nuclear power or a renewable energy). Chemical decomposition or analysis is the separation of a Chemical compound into elements or smaller compounds Fossil fuels or mineral fuels are fossil source Fuels that is Hydrocarbons found within the top layer of the Earth’s crust. Nuclear power is any Nuclear technology designed to extract usable Energy from atomic nuclei via controlled Nuclear reactions Renewable energy is Energy generated from Natural resources mdashsuch as Sunlight, Wind, Rain, tides and geothermal The economics and environmental impact of any implementation of any future hydrogen economy will largely be determined by future energy development. Economics is the social science that studies the production distribution, and consumption of goods and services. See also Nature The natural environment, commonly referred to simply as the environment, is a terminology that is comprised of all living and Energy development is the ongoing effort to provide sufficient Primary energy sources and secondary Energy forms to meet civilization's needs
Biohydrogen can be produced in an algae bioreactor. Biological hydrogen production is done in a Bioreactor based on the production of hydrogen by Algae. Biohydrogen is Hydrogen produced via Biological processes Fermentation Biohydrogen gas can be extracted from Biomass through Dark fermentation Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Biochemical engineering is a branch of Chemical engineering or Biological engineering that mainly deals with the design and construction of unit processes that In the late 1990s it was discovered that if the algae is deprived of sulfur it will switch from the production of oxygen, i. Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the e. normal photosynthesis, to the production of hydrogen. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy.
It seems that the production is now economically feasible by trespassing the 7–10 percent energy efficiency (the conversion of sunlight into hydrogen) barrier.
Biohydrogen can and is produced in bioreactors that utilize feedstocks other than algae, the most common feedstock being waste streams. The process involves bacteria feeding on hydrocarbons and exhaling hydrogen and CO2. The CO2 can be sequestered successfully by several methods, leaving hydrogen gas. A prototype hydrogen bioreactor using waste as a feedstock is in operation at Welch's grape juice factory in North East, Pennsylvania.
The predominant methods of hydrogen production rely on exothermic chemical reactions of fossil fuels to provide the energy needed to chemically convert feedstock into hydrogen. Hydrogen Challenger is a 66 meter (216' 6" refitted coastal tanker for mobile Hydrogen production, it is fitted with a Vertical axis wind turbine But when the energy supply is mechanical (hydropower or wind turbines), hydrogen can be made via electrolysis of water. Electrolysis of water is the decomposition of Water (H2O into Oxygen (O2 and Hydrogen gas (H2 In current market conditions, the 50 kWh of electricity consumed to manufacture one kilogram of hydrogen is roughly as valuable as the hydrogen produced, assuming 8 cents/kWh. The price equivalence, despite the inefficiencies of electrical production and electrolysis, are due to the fact that most hydrogen is made from fossil fuels which couple more efficiently to producing the chemical directly, than they do to producing electricity. However, this is of no help to a hydrogen economy, which must derive hydrogen from any source other than fossil fuels if it is to achieve the goals which primarily drive it. 
Hydrogen can be generated from energy supplied in the form of heat (e. g. , that of concentrating solar thermal or nuclear) and electricity through high-temperature electrolysis (HTE). High-temperature electrolysis (also HTE or steam electrolysis) is a method currently being investigated for the production of Hydrogen from water with In contrast with low-temperature electrolysis, HTE of water converts more of the initial heat energy into chemical energy (hydrogen), potentially doubling efficiency, to about 50%. In Physics, heat, symbolized by Q, is Energy transferred from one body or system to another due to a difference in Temperature Fuel efficiency, in its basic sense is the same as Thermal efficiency, meaning the efficiency of a process that converts chemical potential energy contained in a carrier Because some of the energy in HTE is supplied in the form of heat, less of the energy must be converted twice (from heat to electricity, and then to chemical form), and so potentially far less energy is required per kilogram of hydrogen produced. HTE has been demonstrated in a laboratory, but not at a commercial scale. 
HTE processes are generally only considered in combination with a nuclear heat source, because the only other non-chemical form of high-temperature heat (concentrating solar thermal) is not consistent enough to bring down the capital costs of the HTE equipment. It is possible that research into HTE and high-temperature nuclear reactors may eventually lead to a hydrogen supply that is cost-competitive with natural gas steam reforming. For example, some prototype Generation IV reactors have coolant exit temperatures of 850 to 1000 degrees Celsius, considerably hotter than existing commercial nuclear power plants. Generation IV reactors (Gen IV are a set of theoretical nuclear reactor designs currently being researched The Celsius Temperature scale was previously known as the centigrade scale. Nuclear power is any Nuclear technology designed to extract usable Energy from atomic nuclei via controlled Nuclear reactions High temperature (950–1000 °C) gas cooled nuclear reactors have the potential to split hydrogen from water by thermochemical means using nuclear heat. General Atomics predicts that hydrogen produced in a High Temperature Gas Cooled Reactor (HTGR) would cost $1. General Atomics is a nuclear physics and Defense contractor headquartered in San Diego California. 53/kg. (The first commercial generation IV reactors are expected around 2030). In 2003, steam reforming of natural gas yielded hydrogen at $1. 40/kg. At 2005 natural gas prices, hydrogen costs $2. 70/kg.
One side benefit of a nuclear reactor that produces both electricity and hydrogen is that it can shift production between the two. For instance, the plant might produce electricity during the day and hydrogen at night, matching its electrical generation profile to the daily variation in demand, and offloading the extra output at night into a storable medium for energy.
Some thermochemical processes, such as the sulfur-iodine cycle, can produce hydrogen and oxygen from water and heat without using electricity. The sulfur-iodine cycle (S-I cycle is a series of thermochemical processes used to produce hydrogen. These processes can be more efficient than high-temperature electrolysis. Thermochemical production of hydrogen using chemical energy from coal or natural gas is generally not considered, because the direct chemical path is more efficient.
None of the thermochemical hydrogen production processes have been demonstrated at production levels, although several have been demonstrated in laboratories.
Hydrogen is the product of a number of chemical reactions with metals. Sodium is a classic example, with water and sodium metal reacting to form sodium hydroxide and hydrogen. Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22 Sodium hydroxide ( Na[[hydroxide OH]]) also known as Lye, caustic soda and (incorrectly according to IUPAC nomenclature Another example which has gained some recent interest is aluminium (as an aluminium/gallium alloy) reacting with water to produce aluminium oxide and hydrogen. WikipediaNaming Gallium (ˈgæliəm is a Chemical element that has the symbol Ga and Atomic number 31 An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has  In all cases the pure metal is consumed.
Although molecular hydrogen has very high energy density on a mass basis, due in part to its low molecular weight, as a gas at ambient conditions it has very low energy density by volume. See also Hydrogen economy Hydrogen storage describes the methodologies for storing H2 for subsequent use The molecular mass (abbreviated m of a substance, more commonly referred to as molecular weight and abbreviated as MW, is the Mass of one If it is to be used as fuel stored on board the vehicle, pure hydrogen gas must be pressurized or liquefied to provide sufficient driving range. Increasing gas pressure improves the energy density by volume, making for smaller, but not lighter container tanks (see pressure vessel). A pressure vessel is a closed container designed to hold gases or liquids at a Pressure different from the ambient Pressure. Achieving higher pressures necessitates greater use of external energy to power the compression. Alternatively, higher volumetric energy density liquid hydrogen may be used. However liquid hydrogen is cryogenic and boils at 20. 268 K (–252. 882 °C or –423. 188 °F). Cryogenic storage cuts weight but requires large liquification energies. Cryogenics is often used incorrectly to refer to Cryonics, cryopreserving humans or animals In Physics, to liquefy (sometimes spelled liquify) means to turn something into the Liquid state The liquefaction process, involving pressurizing and cooling steps, is energy intensive. The liquefied hydrogen has lower energy density by volume than gasoline by approximately a factor of four, due to the low density of liquid hydrogen — there is actually more hydrogen in a liter of gasoline (116 grams) than there is in a liter of pure liquid hydrogen (71 grams). Liquid hydrogen storage tanks must also be well insulated to minimize boil off. A Hydrogen tank (other names- cartridge or Canister) is used for Hydrogen storage, most tanks are made of Composite material because of Hydrogen embrittlement Ice may form around the tank and help corrode it further if the liquid hydrogen tank insulation fails.
The mass of the tanks needed for compressed hydrogen reduces the fuel economy of the vehicle. Because it is a small, energetic molecule, hydrogen tends to diffuse through any liner material intended to contain it, leading to the embrittlement, or weakening, of its container. Hydrogen embrittlement (or hydrogen grooving) is the process by which various metals most importantly high-strength Steel, become brittle and crack following exposure
Distinct from storing molecular hydrogen, hydrogen can be stored as a chemical hydride or in some other hydrogen-containing compound. Hydride is the name given to the negative Ion of Hydrogen, H− Hydrogen gas is reacted with some other materials to produce the hydrogen storage material, which can be transported relatively easily. At the point of use the hydrogen storage material can be made to decompose, yielding hydrogen gas. As well as the mass and volume density problems associated with molecular hydrogen storage, current barriers to practical storage schemes stem from the high pressure and temperature conditions needed for hydride formation and hydrogen release. For many potential systems hydriding and dehydriding kinetics and heat management are also issues that need to be overcome. Chemical kinetics, also known as reaction kinetics is the study of rates of chemical processes
A third approach is to absorb molecular hydrogen into a solid storage material. Absorption, in Chemistry, is a physical or chemical Phenomenon or a process in which Atoms Molecules, or Ions enter some Unlike in the hydrides mentioned above, the hydrogen does not dissociate/recombine upon charging/discharging the storage system, and hence does not suffer from the kinetic limitations of many hydride storage systems. Hydrogen densities similar to liquefied hydrogen can be achieved with appropriate absorption media. Some suggested absorbers include MOFs, nanostructured carbons (including CNTs) and clathrate hydrate. Metal-Organic Frameworks (MOFs are Crystalline compounds consisting of metal ions or clusters coordinated to often rigid organic molecules to form one- two- or three-dimensional A nanostructure is an object of intermediate size between Molecular and Microscopic ( micrometer -sized Structures In describing nanostructures See also Graphene, Buckypaper Carbon nanotubes (CNTs are Allotropes of carbon with a nanostructure that can have a length-to-diameter Clathrate hydrates (or gas clathrates gas hydrates clathrates hydrates etc were first documented in 1810 by Sir Humphrey Davy; they are crystalline
The most common method of on board hydrogen storage in today's demonstration vehicles is as a compressed gas at pressures of roughly 700 bar (70 MPa). Many people believe that the energy needed to compress hydrogen to these pressures presents a major barrier to a hydrogen economy. For example, if one considers the entire world using hydrogen just in their cars, then a large amount of energy would be needed simply to compress the hydrogen for storage, of the order of 30% of the total energy used for transport. If this energy was not recovered in any way, the net energy used to compress it would be wasted. Currently, vehicle fuel cells are very expensive, typically 100 times more expensive per kW output than conventional internal combustion engines. It further has been suggested that cars utilizing Li-ion or Li-polymer batteries for onboard energy storage are capable of being more efficient than hydrogen-fueled cars would ever be, and that they just need to be mass produced to become cost effective. Lithium-ion batteries (sometimes abbreviated Li-ion batteries) are a type of Rechargeable battery in which a Lithium ion moves between the Anode Lithium-ion polymer batteries, polymer lithium ion, or more commonly lithium polymer batteries (abbreviated Li-poly Li-Pol LiPo LIP PLI or LiP are
The hydrogen infrastructure consists mainly of industrial hydrogen pipeline transport and hydrogen-equipped filling stations like those found on a hydrogen highway. A hydrogen infrastructure is composed of the structural elements that provide the framework supporting the hydrogen fueling infrastructure Hydrogen pipeline transport is a transportation of hydrogen through a pipe as part of the Hydrogen infrastructure. See also [[Hydrogen infrastructure]] A hydrogen highway is a chain of Hydrogen -equipped filling stations and other infrastructure along a Road Hydrogen stations which are not situated near a hydrogen pipeline get supply via hydrogen tanks, hydrogen tube trailers, liquid tankers or dedicated onsite production. A hydrogen station is a storage or Filling station for Hydrogen, usually located along a road or Hydrogen highway, or at home as part of the Distributed A Hydrogen tank (other names- cartridge or Canister) is used for Hydrogen storage, most tanks are made of Composite material because of Hydrogen embrittlement
Because of hydrogen embrittlement of steel, natural gas pipes have to be coated on the inside with carbon fibers. Hydrogen embrittlement (or hydrogen grooving) is the process by which various metals most importantly high-strength Steel, become brittle and crack following exposure Proponents of the hydrogen economy envision local hydrogen sources. The challenges that large, rural high-efficiency hydrogen generators face are far more acute in an urban environment. Thus, some kind of transmission system will probably be required for cities.
Hydrogen use would require the alteration of industry and transport on a scale never seen before in history. For example, according to GM, 70% of the U. S. population lives near a hydrogen-generating facility but has just about no access to hydrogen, despite its wide availability for commercial use.  The distribution of hydrogen fuel for vehicles in the U. S. would require new hydrogen stations costing 20 billion dollars.  and 4. 6 billion in the EU. 
In a future (full) hydrogen economy, primary energy sources and feedstock would be used to produce hydrogen gas as stored energy for use in various sectors of the economy. Producing hydrogen from primary energy sources other than coal, oil, and natural gas, would result in lower production of the greenhouse gases characteristic of the combustion of these fossil energy resources.
One key feature of a hydrogen economy is that in mobile applications (primarily vehicular transport) energy generation and use is decoupled. The primary energy source need no longer travel with the vehicle, as it currently does with hydrocarbon fuels. Instead of tailpipes creating dispersed emissions, the energy (and pollution) can be generated from point sources such as large-scale, centralized facilities with improved efficiency. This allows the possibility of technologies such as carbon sequestration, which are otherwise impossible for mobile applications. Alternatively, distributed energy generation schemes (such as small scale renewable energy sources) can be used, possibly associated with hydrogen stations. Distributed generation, also called on-site generation, dispersed generation, embedded generation, decentralized generation, decentralized A hydrogen station is a storage or Filling station for Hydrogen, usually located along a road or Hydrogen highway, or at home as part of the Distributed
Aside from the energy generation, hydrogen production could be centralized, distributed or a mixture of both. While generating hydrogen at centralized primary energy plants promises higher hydrogen production efficiency, difficulties in high-volume, long range hydrogen transportation (due to factors such as hydrogen damage and the ease of hydrogen diffusion through solid materials) makes electrical energy distribution attractive within a hydrogen economy. Hydrogen damage is the generic name given to a large number of Metal degradation processes due to interaction with Hydrogen. In such a scenario, small regional plants or even local filling stations could generate hydrogen using energy provided through the electrical distribution grid. While hydrogen generation efficiency is likely to be lower than for centralized hydrogen generation, losses in hydrogen transport can make such a scheme more efficient in terms of the primary energy used per kilogram of hydrogen delivered to the end user.
The proper balance between hydrogen distribution and long-distance electrical distribution is one of the primary questions that arises in the hydrogen economy.
An accounting of the energy utilized during a thermodynamic process, known as an energy balance, can be applied to automotive fuels. With today's technology, the manufacture of hydrogen via steam reforming can be accomplished with a thermal efficiency of 75 to 80 percent. Steam reforming (SR hydrogen reforming or catalytic oxidation, is a method of producing Hydrogen from Hydrocarbons. Additional energy will be required to liquefy or compress the hydrogen, and to transport it to the filling station via truck or pipeline. The energy that must be utilized per kilogram to produce, transport and deliver hydrogen (i. e. , its well-to-tank energy use) is approximately 50 megajoules. Subtracting this energy from the enthalpy of one kilogram of hydrogen, which is 141 megajoules, and dividing by the enthalpy, yields a thermal energy efficiency of roughly sixty percent.  Gasoline, by comparison, requires less energy input, per gallon, at the refinery, and comparatively little energy is required to transport it and store it owing to its high energy density per gallon at ambient temperatures. Well-to-tank, the supply chain for gasoline is roughly 80 percent efficient (Wang, 2002). The most efficient distribution however is electrical, which is typically 95% efficient. Electric vehicles are typically 3 to 4 times as efficient as hydrogen powered vehicles. An electric car is a type of alternative fuel Car that utilizes Electric motors and Motor controllers instead of an Internal combustion engine A hydrogen vehicle is a Vehicle that uses Hydrogen as its on-board fuel for motive power 
Another pathway proposed for hydrogen production is distributed electrolysis. This method would bypass the problems of distributing hydrogen somewhat by distributing electricity instead. It would take advantage of existing infrastructure to transport electricity to small, on-site electrolysers located at filling stations. Hydrogen can be produced through electrolysis of water, which is roughly 70 percent efficient (using the lower heating value for hydrogen). However, accounting for the energy used to produce the electricity (i. e. , enlarging the system boundary) and accounting as well for transmission losses will reduce this efficiency.
Natural gas combined cycle power plants, which account for almost all builds of new electricity plants in the United States, generate electricity at efficiencies of 60 percent or greater. Increased demand for electricity, whether due to hydrogen cars or other demand, would have the marginal impact of adding new combined cycle power plants. On this basis, distributed production of hydrogen would be roughly 40 percent efficient. However, if the marginal impact is referred to today's power grid, with an efficiency of roughly 40 percent owing to its mix of fuels and conversion methods, the efficiency of distributed hydrogen production would be roughly 25 percent. (Note that, analogous to hydrogen production from a fossil fuel, gasoline must be refined from crude oil, the "primary energy resource". )
The distributed production of hydrogen in this fashion will be expected to generate air emissions of pollutants and carbon dioxide at various points in the supply chain, e. g. , electrolysis, transportation and storage. Such externalities as pollution must be weighed against the potential advantages of a hydrogen economy. Other fuel cell technologies based on the exchange of metal ions (i. e. zinc-air fuel cells) are typically more efficient at energy conversion than hydrogen fuel cells, but the widespread use of any electrical energy → chemical energy → electrical energy systems would necessitate the production of electricity. Zinc-air batteries (non-rechargeable and zinc-air Fuel cells (mechanically-rechargeable are electro-chemical batteries powered by the Oxidation
In summary, the so-called production problem is seen to be a combination of two different problems: one of producing hydrogen efficiently from energy sources, and the other of locating suitable (renewable or at least less polluting) energy sources to do it.
One of the main offerings of a hydrogen economy is that fuel cells can replace internal combustion engines and turbines as the primary way to convert chemical energy into kinetic or electrical energy. A fuel cell is an electrochemical conversion device It produces electricity from Fuel (on the Anode side and an oxidant (on the The internal combustion engine is an engine in which the Combustion of Fuel and an Oxidizer (typically air occurs in a confined space called a A turbine is a rotary Engine that extracts Energy from a Fluid flow The reason to expect this changeover is that fuel cells, being electrochemical, are usually (and theoretically) more efficient than heat engines. Electrochemistry is a branch of Chemistry that studies Chemical reactions which take place in a Solution at the interface of an electron conductor Currently, fuel cells are more expensive to produce than common internal combustion engines, but are becoming cheaper as new technologies and production systems develop.
Some types of fuel cells work with hydrocarbon fuels while all can be operated on pure hydrogen. In the event that fuel cells become price-competitive with internal combustion engines and turbines, large gas-fired power plants could adopt this technology. Such commercialization would be an important step in driving down the cost of fuel cell technology.
Much of the interest in the hydrogen economy concept is focused on the use of fuel cells in cars. The cells can have a superior power-to-weight ratio, are much more efficient than internal combustion engines, and produce no harmful emissions. If a practical and engineer-able method to store and carry hydrogen is introduced and fuel cells become cheaper, they can be economically viable to power hybrid fuel cell/battery vehicles, or purely fuel cell-driven ones. See also Hydrogen economy Hydrogen storage describes the methodologies for storing H2 for subsequent use A hybrid vehicle is a vehicle that uses two or more distinct power sources to propel the vehicle In electronics a battery is a combination of two or more Electrochemical cells which store chemical Energy which can be converted into electrical energy The economic viability of fuel cell powered vehicles will improve as the hydrocarbon fuels used in internal combustion engines become more expensive, due to the depletion of easily accessible reserves or economic accounting of environmental impact through such measures as carbon taxes. A carbon tax is an environmental Tax on emissions of Carbon dioxide and other Greenhouse gases It is an example of a pollution tax.
Currently it takes 2½ times as much energy to make a hydrogen fuel cell than is obtained from it during it's service life. 
When evaluating costs, Oil and Gas (fossil fuels) are generally used as the cheapest reference, even though the true cost of those fuels is seldom considered. Being fossil fuels — a non-renewable source of energy — the millions of years required to be formed inside the Earth seem to mean "no cost" in most calculations and only the production costs are considered. Given such calculated low cost reference, any number of watts required for hydrogen production seem too much even if those watts come from a rather opposite — renewable — source of power like the Sun.
From the above, Hydrogen seems unlikely to be the cheapest carrier of energy over long distances. Advances in electrolysis and fuel cell technology have not addressed the underlying cost problem.
Hydrogen pipelines are more expensive than even long-distance electric lines. Hydrogen is about three times bulkier in volume than natural gas for the same enthalpy, and hydrogen accelerates the cracking of steel (hydrogen embrittlement), which increases maintenance costs, leakage rates, and material costs. In Thermodynamics and molecular chemistry, the enthalpy (denoted as H, h, or rarely as χ) is a quotient or description of Hydrogen embrittlement (or hydrogen grooving) is the process by which various metals most importantly high-strength Steel, become brittle and crack following exposure The difference in cost is likely to expand with newer technology: wires suspended in air can utilize higher voltage with only marginally increased material costs, but higher pressure pipes require proportionally more material.
Setting up a hydrogen economy would require huge investments in the infrastructure to store and distribute hydrogen to vehicles. In contrast, battery electric vehicles, which are already publicly available, would not necessitate immediate expansion of the existing infrastructure for electricity transmission and distribution, since much of the electricity currently being generated by power plants goes unused at night when the majority of electric vehicles would be recharged. The battery electric vehicle, or BEV, is a type of Electric vehicle (EV that uses chemical Energy stored in Rechargeable battery A study conducted by the Pacific Northwest National Laboratory for the US Department of Energy in December 2006 found that the idle off-peak grid capacity in the US would be sufficient to power 84% of all vehicles in the US if they all were immediately replaced with electric vehicles. 
Different production methods each have differing associated investment and marginal costs. The energy and feedstock could originate from a multitude of sources i. e. natural gas, nuclear, solar, wind, biomass, coal, other fossil fuels, and geothermal.
Hydrogen gas can be created through the natural gas steam reforming/water gas shift reaction method, outlined above. This creates carbon dioxide (CO2), a greenhouse gas, as a byproduct. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared This is usually released into the atmosphere, although there has also been some research into interring it underground or undersea. The steam reformers in methane-based fuel cells convert hydrocarbons into either carbon dioxide or carbon monoxide (CO). Methane is a Chemical compound with the molecular formula. It is the simplest Alkane, and the principal component of Natural gas. A fuel cell is an electrochemical conversion device It produces electricity from Fuel (on the Anode side and an oxidant (on the In Organic chemistry, a hydrocarbon is an Organic compound consisting entirely of Hydrogen and Carbon. Carbon monoxide, with the chemical formula CO is a colorless odorless tasteless yet highly toxic Gas. 
Recently, there have also been some concerns over possible problems related to hydrogen gas leakage, (this has been pointed out in a paper published in Science magazine by a group of Caltech scientists). Molecular hydrogen leaks slowly from most containment vessels. It has been hypothesized that if significant amounts of hydrogen gas (H2) escape, hydrogen gas may, due to ultraviolet radiation, form free radicals (H) in the stratosphere. In Chemistry, radicals (often referred to as free radicals) are atoms molecules or ions with Unpaired electrons on an otherwise Open shell These free radicals would then be able to act as catalysts for ozone depletion. Ozone depletion describes two distinct but related observations a slow steady decline of about 4 percent per decade in the total amount of Ozone in Earth's A large enough increase in stratospheric hydrogen from leaked H2 could exacerbate the depletion process. However, the effect of these leakage problems may not be significant. The amount of hydrogen that leaks today is much lower (by a factor of 10–100) than the estimated 10–20% figure conjectured by some researchers; for example, in Germany, the leakage rate is only 0. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. 1% (less than the natural gas leak rate of 0. 7%). At most, such leakage would likely be no more than 1–2% even with widespread hydrogen use, using present technology. 
Hydrogen has been feared in the popular press as a relatively more dangerous fuel, and hydrogen in fact has the widest explosive/ignition mix range with air of all the gases except acetylene. Hydrogen also usually escapes rapidly after containment breach. Additionally, hydrogen flames are difficult to see, so may be difficult to fight. An experiment performed at the University of Miami attempted to counter this by showing that hydrogen escapes while gasoline remains by setting alight hydrogen- and petrol-fuelled vehicles. 
In the LZ 129 Hindenburg disaster, 2/3 of passengers and crew survived, though the skin of the Hindenburg may have contributed. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout It was concluded at the time by the board of enquiry that the fire was cause by electrostatic discharge of hydrogen leaking from the rear of the craft. Electrostatic discharge ( ESD) is the sudden and momentary Electric current that flows between two objects at different Electrical potentials The term is Recent research indicates that the outer fabric was highly inflammable, and that electrostatic sparks ignited the fabric first, which then spread to the hydrogen within. Electrostatics is the branch of Science that deals with the Phenomena arising from what seems to be stationary Electric charges Since Classical
In a more recent event, an explosion of compressed hydrogen during delivery at the AEP Muskingum River Coal Plant caused significant damage and killed one person. American Electric Power ( is a major investor-owner Electric utility in various parts of the United States. 
One of the measures on the roadmap is to implement higher safety standards like early leak detection with hydrogen microsensors. A hydrogen microsensor is a Gas detector that detects the presence of Hydrogen. 
(For comparison: Deflagration limit of gasoline in air: 1. 4–7. 6%)
As per chapters 4 through 6 of the document, hydrogen collects under roofs and overhangs, where it forms an explosion hazard; any building that contains a potential source of hydrogen should have good ventillation, strong ignition suppression systems for all electric devices, and preferably be designed to have a roof that can be safely blown away from the rest of the structure in an explosion. It also enters pipes and can follow them to their destinations.
Several domestic U.S. automobile manufactures have committed to develop vehicles using hydrogen. The United States of America —commonly referred to as the (They had previously committed to producing electric vehicles in California, a program now defunct at their behest. The Electric Vehicle was an American Automobile manufactured only in 1899 ) Critics argue this "commitment" is merely a ploy to sidestep calls for increased efficiency in gasoline and diesel fuel powered vehicles and diverts us from needed steps to address global warming, such as greater focus on conservation, green fuel production and other green technologies. Diesel or Diesel fuel (ˈdiːzəl in general is any Fuel used in Diesel engines The most common is a specific fractional distillate of petroleum The distribution of hydrogen for the purpose of transportation is currently being tested around the world, particularly in Portugal, Iceland, Norway, Denmark, Germany, California, Japan and Canada, but the cost is very high. Portugal, officially the Portuguese Republic (República Portuguesa is a country on the Iberian Peninsula. Iceland, officially the Republic of Iceland ( ( Ísland or Lýðveldið Ísland ( The Hynor Hydrogen highway in Norway was established in 2003 and is part of the Scandinavian hydrogen highway partnership with hyfuture and hydrogen The Hydrogen link network in Denmark was established in 2005 by the Nordic Transportpolitical Network to form a Hydrogen highway with Hydrogen Sweden and Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. The California Hydrogen Highway is a series of hydrogen refueling stations in California. The Japan hydrogen fuel cell project is a project started in 2002 with activities related to Hydrogen vehicles.
Some hospitals have installed combined electrolyzer-storage-fuel cell units for local emergency power. These are advantageous for emergency use due to their low maintenance requirement and ease of location compared to internal combustion driven generators.
The North Atlantic island country of Iceland has committed to becoming the world's first hydrogen economy by the year 2050. Iceland, officially the Republic of Iceland ( ( Ísland or Lýðveldið Ísland (  Iceland is in a unique position. Presently, it imports all the petroleum products necessary to power its automobiles and fishing fleet. A fishing fleet is an aggregate of commercial Fishing vessels. Iceland has large geothermal resources, so much that the local price of electricity actually is lower than the price of the hydrocarbons that could be used to produce that electricity.
Iceland already converts its surplus electricity into exportable goods and hydrocarbon replacements. In 2002, it produced 2,000 tons of hydrogen gas by electrolysis-- primarily for the production of ammonia (NH3) for fertilizer. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor Ammonia is produced, transported, and used throughout the world, and 90% of the cost of ammonia is the cost of the energy to produce it. Iceland is also developing an aluminium -smelting industry. Aluminium costs are primarily driven by the cost of the electricity to run the smelters. Either of these industries could effectively export all of Iceland's potential geothermal electricity.
Neither industry directly replaces hydrocarbons. Reykjavík, Iceland, had a small pilot fleet of city buses running on compressed hydrogen, and research on powering the nation's fishing fleet with hydrogen is under way. For the Greater Reykjavík Area see the Greater Reykjavík Area. For more practical purposes, Iceland might process imported oil with hydrogen to extend it, rather than to replace it altogether.
The Reykjavík buses are part of a larger program, HyFLEET:CUTE, operating hydrogen fueled buses in eight European cities. HyFLEET:CUTE buses also operate in Beijing and Perth (see below).
A pilot project demonstrating a hydrogen economy is operational on the Norwegian island of Utsira. Norway ( Norwegian: Norge ( Bokmål) or Noreg ( Nynorsk) officially the Kingdom of Norway, is a Constitutional Utsira is a municipality in the county of Rogaland, Norway. Utsira was separated from Torvastad July 1 1924 The installation combines wind power and hydrogen power. Wind Power is the conversion of wind energy into a useful form such as electricity using Wind turbines At the end of 2007 worldwide capacity of wind-powered generators was In periods when there is surplus wind energy, the excess power is used for generating hydrogen by electrolysis. In chemistry and manufacturing electrolysis is a method of separating chemically bonded elements and compounds by passing an Electric current The hydrogen is stored, and is available for power generation in periods when there is little wind.
A joint venture between NREL and Xcel Energy is combining wind power and hydrogen power in the same way in Colorado. The National Renewable Energy Laboratory (NREL located in Golden Colorado, as part of the U Xcel Energy Inc ( is a Public utility company based in Minneapolis Minnesota, serving customers in Colorado, Michigan, Minnesota Wind Power is the conversion of wind energy into a useful form such as electricity using Wind turbines At the end of 2007 worldwide capacity of wind-powered generators was 
Hydro in Newfoundland and Labrador are converting the current wind-diesel Power System on the remote island of Ramea into a Wind-Hydrogen Hybrid Power Systems facility. Newfoundland and Labrador Hydro is a provincial Crown corporation that provides hydroelectric power for Newfoundland and Labrador, Canada. Newfoundland and Labrador (ˈnuːfɨn(dlənd ən(d ˈlæbrəˌdɔr (Terre-Neuve-et-Labrador is a province of Canada, the tenth and latest to join the Confederation Wind-diesel Hybrid Power Systems are designed to provide electrical generating capacity to remote communities and facilities that are not linked to a power grid Ramea Newfoundland and Labrador ( NST) is a small town located on Northwest Island one of a group of five major islands One of the key issues with Wind energy is its intermittent nature. 
A similar pilot project on Stuart Island uses solar power, instead of wind power, to generate electricity. Stuart Island is located in the San Juan Islands of Washington state USA, north of San Juan Island and west of Waldron Island. Solar energy is the Light and radiant heat from the Sun that powers Earth 's Climate and Weather and sustains Life Wind Power is the conversion of wind energy into a useful form such as electricity using Wind turbines At the end of 2007 worldwide capacity of wind-powered generators was When excess electricity is available after the batteries are full, hydrogen is generated by electrolysis and stored for later production of electricity by fuel cell. 
The UK started a fuel cell pilot program in January 2004, the program ran two Fuel cell buses on route 25 in London until December 2005, and switched to route RV1 until January 2007. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located London ( ˈlʌndən is the capital and largest urban area in the United Kingdom. 
The Hydrogen Expedition is currently working to create a hydrogen fuel cell-powered ship and using it to circumnavigate the globe, as a way to demonstrate the capability of hydrogen fuel cells. 
Western Australia's Department of Planning and Infrastructure currently operates three Daimler Chrysler Citaro fuel cell buses as part of its Sustainable Transport Energy for Perth Fuel Cells Bus Trial in Perth.  The buses are operated by Path Transit on regular Transperth public bus routes. The trial began in September 2004 and concluded in September 2006. The buses' fuel cells use a proton exchange membrane system and are supplied with raw hydrogen from a BP refinery in Kwinana, south of Perth. The hydrogen is a byproduct of the refinery's industrial process. The buses are refueled at a station in the northern Perth suburb of Malaga.
Hydrogen is simply a method to store and transmit energy. Various alternative energy transmission and storage scenarios may be more economic, in both near and far term. These include:
Hydrogen storage has been proposed by some to be optimal in a narrow range of energy storage time, probably somewhere between a few days and a few weeks. A plug-in hybrid electric vehicle ( PHEV) is a Hybrid vehicle with batteries that can be recharged by connecting a plug to an Electric power This range is subject to further narrowing with any improvements in battery technology. It is always possible that some kind of breakthrough in hydrogen storage or generation could occur, but this is unlikely given the physical and chemical limitations of the technical choices are fairly well understood. See also alternative fuel, zinc economy, lithium economy or liquid nitrogen economy, hydrocarbon economy, low-carbon economy. Alternative fuels, also known as non-conventional Fuels are any Materials or substances that can be used as a Fuel, other than conventional fuels Zinc-air batteries (non-rechargeable and zinc-air Fuel cells (mechanically-rechargeable are electro-chemical batteries powered by the Oxidation The lithium economy is a concept analogous to the Hydrogen economy, Methanol economy, Ethanol economy, electron economy Vegetable oil economy A liquid nitrogen economy is a hypothetical proposal for a future Economy in which the primary form of energy storage and transport is Liquid nitrogen. Hydrocarbon economy is a term stressing that in the current world economy the energy used mostly comes from three Hydrocarbons Petroleum, Coal A Low-Carbon Economy (LCE or Low Fossil Fuel Economy (LFFEis a popular term that refers to an Economy which has a minimal output of Greenhouse Gas (GHG emissions into the