Definition
Basic
On a weight basis, hydrogen has nearly three times the energy content of gasoline (120 MJ/kg for hydrogen versus 44 MJ/kg for gasoline). However, on a volume basis the situation is reversed (8 MJ/litre for liquid hydrogen versus 32 MJ/litre for gasoline). This means that a way of storing the amount of hydrogen needed for a certain application, for example for a driving distance of 300 km, is required.
Hydrogen storage describes the methods for storing hydrogen for subsequent use as energy source. It is a main goal in the development of the hydrogen society and it is a key enabling technology for the advancement of hyrogen and fuel cell power technologies in transportation, stationary and portable applications.
Commodification
Hydrogen is the most abundant element in the universe, but molecular hydrogen is not available on Earth, as most of it is bonded to oxygen in water. Currently, the dominant technology for direct production of this element is steam reforming from hydrocarbons. Some other less effective methods are electrolysis of water and thermolysis.
Once hydrogen is produced, it needs to be stored. Hydrogen can be compressed and stored in tanks at high pressures, or stored into liquid form. Another approach is to store it in metal hydrides, compounds that can store hydrogen in their structure and release it under certain temperature and pressure conditions.
Hydrogen can then be converted to energy via traditional combustion methods and through electrochemical processes in devices called “fuel cells”.
History
Origin
Hydrogen is a chemical element with atomic number 1 and it is represented by the symbol H. Robert Boyle (1627-1691), an English chemist and physicist, published a paper ("New experiments touching the relation betwixt flame and air") in 1671 in which he described the reaction between iron filings and dilute acids which results in the evolution of gaseous hydrogen.
However it was only much later that it was recognized as an element by Henry Cavendish (1731-1810) in 1766 when he collected it over mercury and described it as "inflammable air from metals". The name comes from the Greek words “hydro” and “genes” meaning “water” and “generator”.
The first hydrogen-filled balloon was invented by Jacques Charles in 1783. Hydrogen provided the lift for the first reliable fo
javascript:nicTemp();rm of air-travel following the 1852 invention of the first hydrogen-lifted airship by Henri Giffard. German count Ferdinand von Zeppelin promoted the idea of rigid airships lifted by hydrogen that later were called Zeppelins; the first of which had its maiden flight in 1900.
Regularly scheduled flights started in 1910 and by the outbreak of World War I in August 1914, they had carried 35,000 passengers without a serious incident. Hydrogen-lifted airships were used as observation platforms and bombers during the war.
In 1937 the first hydrogen-cooled turbogenerator went into service with gaseous hydrogen as a coolant in the rotor. The nickel hydrogen battery was used for the first time in 1977 aboard the U.S. Navy's Navigation technology satellite-2 (NTS-2).
Hoffmann, Peter
Popular Use
In 1838 the fuel cell effect, combining hydrogen and oxygen gases to produce water and en electric current, was discovered by the Swiss chemist Christian Friedrich Schoenbein. In 1845 Sir William Grove demonstrated the Schoenbein’s discovery on a practical scale by creating a “gas battery”. For this achievement he is known as the “Father of the Fuel Cell”.
In the 70s, the OPEC oil embargo and the resulting supply shock showed that alternative fuels were needed, and as a result, development of hydrogen fuel cells for conventional commercial applications began. In the 90s, the first demonstrations of fuel cell vehicles took place.
Money Involved
Investment
Global investments in building the hydrogen economy cost was nearly $2 billion in 2009, and was expected to rise to exceed $2.2 billion in 2010, approaching $5.4 billion by 2015. These figures represent a compound annual growth rate (CAGR) of 19.3% over the next 5 years.
Building enough centralised hydrogen plants to supply the fuel needed to run all the cars, trucks and buses in use in the world today would require a staggering $8 trillion of investment at current costs.
Use
Primary
About 50 million metric tonnes of hydrogen were produced in 2004. Hydrogen is primarily used in the petroleum and chemical industries. The largest application of hydrogen is the processing of fossil fuels and in the production of ammonia, which is then used as fertiliser. Other uses of hydrogen are as hydrogenating agent (increasing the level of saturation of unsaturated fats and oils), in the production of methanol, and as a coolant in generators.
Production
Hydrogen does not naturally exist in its elemental form on Earth; it must be produced from other compounds.
Hydrogen can be produced from natural gas using steam in a process called “steam methane reforming”. 95% of the hydrogen used today in the U.S. is produced in this way. If methane is burned in air instead, then the process is called “partial oxidation”.
Electrolysis of water, consisting of applying an electric current to split water into hydrogen and oxygen is another method. The electricity needed can be produced in a variety of ways, but electricity generated using renewable energy technologies is preferred.
With gasification, coal or biomass are converted into gaseous components by applying heat under pressure in the presence of air/oxygen and steam. The gas undergoes a series of reactions, and hydrogen is obtained.
Transportation
Commonly, hydrogen is produced at or near where I is used, and an efficient way of delivering it over long distances does not yet exist.
Transmission using pipelines is the least expensive way to deliver large amounts. Fot short disntances and not so big amounts, hydrogen is compressed and transported in high-pressure tube trailers. Cryogenic liquid hydrogen tankers is another option for longer distances, but it is costly due to the amount of energy it requires.
Alternative delivery forms are transport of hydrogen in chemical compounds.
Storage
Hydrogen has physical characteristics that make it difficult to store in large quantities without taking up a significant amount of space. For the hydrogen economy to be a reality, hydrogen storage will be required at production sites, onboard vehicles and refueling stations.
The most mature gas technology is the compact storage in gas tanks under high pressure. Cryogenic containers for liquid hydrogen, on the contrary, require less volume than the gas storage, but they consume great quantities of power, equivalent to one third the energy value of the hydrogen.
Another way is to store it in materials: on the surface of solids (by adsorption) or within solids (by absorption). In adsorption, hydrogen attaches to the surface of a material, and in absorption hydrogen atom incorporate into the solid lattice framework. Hydrogen can also be stronlgy bound within molecular structures, as chemical compounds conatining hydrogen atoms (hydrides). When hydrogen need to be used, it is released from these materials under certain conditions of pressure and temperature.
Conversion
Hydrogen is an energy carrier that requires an end-use device to produce heat or electricity.
It can be combusted in the same manner as gasoline, with the benefit of releasing fewer emissions than when fossil fuels are combusted. Some applications are space shuttle’s main engines and internal combustion engine vehicles.
If hydrogen is used in a fuel cell then its energy is converted into electricity and heat. Fuel cells can work with several different fuels, but if hydrogen is used, only water is produced as by-product. Fuels cells can achieve higher efficiencies than internal combustion engines.
Challenges
Production
Hydrogen production costs are high relative to conventional fuels, as the cost per unit of energy delivered through hydrogen when produced from hydrocarbons is higher than the cost of the same unit of energy from the hydrocarbon itself. Current technologies produce large quantities of carbon dioxide, and advanced hydrogen production methods need development. Furthermore, there is little demand of hydrogen as an energy carrier, and its growth will depend on the development of storage and conversion devices.
Delivery
Delivery technologies cost more than conventional fuel delivery. Costumers expect the same degree of convenience, cost performance and safety when dispensing hydrogen fuel as when dispensing conventional fuels, but current dispensing systems are inconvenient and expensive.
Storage
Storage is critical in the hydrogen cycle and improved storage technologies are needed to satisfy end-user expectations and boost consumer confidence in hydrogen-powered alternatives. While compressed and liquid storage are expensive, they would be more affordable if there were more hydrogen-fuelled vehicles on the road.
Conversion
While fuel cell technologies have generated much excitement, they are still in various stages of maturity. Most have not been manufactured in large quantities and numerous performance issues - including durability, reliability, and cost - remain to be resolved. Combustion turbines and engines that use hydrogen or hydrogen/natural gas blends, already in use in both mobile and stationary applications, are much closer to satisfying these criteria than are fuel cells.
Possibilities
Clean Energy
Hydrogen in a clean energy carrier that can be produced from diverse resources, including renewable energy (solar, wind, geothermal). Hydrogen is expected, in the long term, to reduce dependence on oil and emissions of greenhouse gases and other pollutants.
United States Department of Energy
Hydrogen holds the potential to provide energy services to all sectors of the economy: transportation, buildings and industry. It can complement or replace network-based electricity – the other main energy carrier – in final energy uses. Hydrogen can provide storage options for intermittent renewables-based electricity technologies such as solar and wind. Hydrogen may also be an attractive technology for remote communities which cannot economically be supplied with electricity via a grid.
Key Countries
Public R&D Spending on Hydrogen
(in million $US, 2003)
1. Japan - 270
2. United States - 97
3. France - 45
4. Germany - 34
5. Italy - 34
Prospects
Outlook
The leading sources of long-term global energy projections, including the US Energy Information Administrations’ International Energy Outlook 2005 and the IEA’s World Energy Outlook 2005, project hydrogen to play only a marginal role in meeting final energy needs in the next 20-25 years. However, both reports acknowledge that major technological breakthroughs could result in earlier and faster market penetration.
Longer-term scenarios developed by the IEA paint a slightly more optimistic outlook for hydrogen use: in a scenario that assumes a $50 per tonne carbon-dioxide penalty, hydrogen use, mostly for transport, reaches almost 300 million tonnes of oil equivalent – enough to fuel over a quarter of all passenger cars in the world.
Transition to Globalisation
Hydrogen-Powered Buses in Iceland
The world's first hydrogen filling station opened in Reykjavik way back in April 2003, and the city has been using hydrogen-powered buses since. At about $1.67 million apiece (about 3-4 times more than a typical diesel bus), these buses don’t come cheap; on the other hand, they can travel about 400 km on one tank.
Globalisation > Economy > Transportation
Transition to Political Tools
European Commission Promotes Take-Up of Hydrogen Cars and Development of Hydrogen
The European Commission adopted in 2007 two proposals to make a step forward in the development and marketing of clean and safe hydrogen vehicles: setting up of the Fuel Cells and Hydrogen Joint Technology Initiative (JTI). The JTI should accelerate the development of hydrogen technologies to the point of commercial take-off between 2010 and 2020. Secondly, the comission proposed to simplify the approval of hydrogen cars so that they will be seen more often on Europe’s streets.
Political Tools > Regional > Europe > EU > Dom. Policies > Economy > Energy
Transition to Political Actors
European Hydrogen Association
In 2000 five national hydrogen organisations established the European Hydrogen Association (EHA) and started a close collaboration to promote the use of hydrogen as an energy vector in Europe. In 2004 major European industries active in the development of hydrogen and fuel cell technologies joined the EHA and enforced this effort to create a commercial market for stationary and transport applications and a role as market leader for the European hydrogen and fuel cell sector.
The EHA currently represents 19 national hydrogen and fuel cell organisations and the main European companies active in the hydrogen infrastructure development.
Political Actors > Business > Interest Organisations
