Hydrogen is the simplest and lightest element known to exist, with only one proton and one electron per atom. It is an energy carrier, not an energy source—it must be produced from compounds that contain it. It is the most abundant element in the universe and is the source of the energy we receive from the sun, which is essentially a giant hydrogen gas ball. This radiant energy from the sun is important because it provides light and heat and makes plants grow.
On Earth, hydrogen is only found in compound form such as with oxygen to form water and with carbon to form compounds such as methane, coal and petroleum. At room temperature, it is a transparent, highly flammable gas.
How Hydrogen is Formed
Since hydrogen fuel is not found naturally on Earth, it must be manufactured. Hydrogen fuel is a byproduct of chemically mixing hydrogen/oxygen to produce electricity, water and heat. It is stored in a “cell” or battery.
Hydrogen is usually produced through steam reforming or electrolysis. Steam reforming, which is the least expensive way to create hydrogen, involves separating hydrogen atoms from carbon atoms in methane. This method accounts for about 95% of the hydrogen produced in the United States, but the process creates greenhouse gas emissions.
In electrolysis, an electric current is used to split water into hydrogen and oxygen; then the hydrogen can be extracted and used. Nuclear high-temperature electrolysis uses the heat from a nuclear reactor to warm up water before applying an electric current; by warming the water up first, less electricity is needed to separate the hydrogen and oxygen, reducing the energy consumption.
Today, hydrogen is primarily transported short distances via pipeline. In some instances, hydrogen can be transported via tanker trucks or barges. It can also be transported using elements like ammonia or ethanol that contain hydrogen atoms. When hydrogen is transported long distances, it is best to liquefy it and move it in a tanker truck. But liquefaction is expensive and energy-consuming, so it is usually used in close proximity to where it is created to avoid long transports.
History of Hydrogen
Hydrogen was discovered in 1766 by English chemist and physicist Henry Cavendish. It was named in 1788 by French chemist Antoine-Laurent Lavoisier from the Greek words for “water-former.” In 1783, Jacques Alexander Cesar Charles, a French physicist, launched the first hydrogen balloon flight. In the 1950s, NASA began experimenting with hydrogen fuel cells. Today, there is ongoing research and development into making hydrogen more widely used.
1766 – Hydrogen was first identified as a distinct element by British scientist Henry Cavendish after he evolved hydrogen gas by reacting zinc metal with hydrochloric acid. In a demonstration to the Royal Society of London, Cavendish applied a spark to hydrogen gas, yielding water. This discovery led to his later finding that water (H2O) is made of hydrogen and oxygen.
1783 – Jacques Alexander Cesar Charles, a French physicist, launched the first hydrogen balloon flight. Known as “Charliere,” the unmanned balloon flew to an altitude of 3 kilometers. Only three months later, Charles himself flew in his first manned hydrogen balloon.
1788 – Building on the discoveries of Cavendish, French chemist Antoine Lavoisier gave hydrogen its name, which was derived from the Greek words “hydro” and “genes,” meaning “water” and “born of.”
1800s – English scientists William Nicholson and Sir Anthony Carlisle discovered that applying electric current to water produced hydrogen and oxygen gases. This process was later termed “electrolysis.”
1838 – The fuel cell effect, combining hydrogen and oxygen gases to produce water and an electric current, was discovered by Swiss chemist Christian Friedrich Schoenbein.
1920s – German engineer Rudolf Erren converted the internal combustion engines of trucks, buses and submarines to use hydrogen or hydrogen mixtures. British scientist and Marxist writer J.B.S. Haldane introduced the concept of renewable hydrogen in his paper “Science and the Future” by proposing that “there will be great power stations where during windy weather the surplus power will be used for the electrolytic decomposition of water into oxygen and hydrogen.”
1937 – After 10 successful trans-Atlantic flights from Germany to the United States, the Hindenburg, a dirigible inflated with hydrogen gas, crashed upon landing in Lakewood, New Jersey. The mystery of the crash was solved in 1997. A study concluded that the explosion was not due to the hydrogen gas, but rather to a weather-related static electric discharge that ignited the airship’s silver-colored, canvas exterior covering, which had been treated with the key ingredients of solid rocket fuel.
1958 – The United States formed the National Aeronautics and Space Administration (NASA). NASA’s space program currently uses the most liquid hydrogen worldwide, primarily for rocket propulsion and as a fuel for fuel cells.
1959 – Francis T. Bacon of Cambridge University in England built the first practical hydrogen-air fuel cell. The 5-kilowatt (kW) system powered a welding machine. He named his fuel cell design the “Bacon Cell.” Later that year, Harry Karl Ihrig, an engineer for the Allis―Chalmers Manufacturing Company, demonstrated the first fuel cell vehicle: a 20-horsepower tractor. Hydrogen fuel cells, based upon Francis T. Bacon’s design, have been used to generate on-board electricity, heat and water for astronauts aboard the famous Apollo spacecraft and all subsequent space shuttle missions.
1974 – International Energy Agency (IEA) was established in response to global oil market disruptions. IEA activities included the research and development of hydrogen energy technologies.
1997 – German car manufacturer Daimler-Benz and Ballard Power Systems announced a $300 million research collaboration on hydrogen fuel cells for transportation.
1998 – Iceland unveiled a plan to create the first hydrogen economy by 2030 with Daimler-Benz and Ballard Power Systems.
1999 – The Royal Dutch/Shell Company committed to a hydrogen future by forming a hydrogen division. Europe’s first hydrogen fueling stations were opened in the German cities of Hamburg and Munich.
A consortium of Icelandic institutions, headed by the financial group New Business Venture Fund, partnered with Royal Dutch/Shell Group, DaimlerChrysler (a merger of Daimer Benz and Chrysler) and Norsk Hydro to form the Icelandic Hydrogen and Fuel Cell Company Ltd. to further the hydrogen economy in Iceland.
Today – In the future, water will replace fossil fuels as the primary resource for hydrogen. Hydrogen will be distributed via national networks of hydrogen transport pipelines and fueling stations. Hydrogen energy and fuel cell power will be clean, abundant, reliable, affordable and an integral part of all sectors of the economy in all regions of the US.
Uses for Hydrogen
Hydrogen has a variety of important uses, including:
- Refining and treating metals
- Processing foods, such as hydrogenating oils or fats (like what you might find in the margarine in your fridge!)
- Refining crude oil in the petroleum industry
- Providing electricity through fuel cells
The main use for hydrogen, though, is as rocket fuel. Liquid hydrogen fuel is used by NASA to get space shuttles into orbit, and hydrogen batteries power the shuttles’ electrical equipment. The hydrogen’s only byproduct is pure water, which the shuttle crew can use as drinking water!
Hydrogen for Transportation
Hydrogen has the potential to make a huge impact on the world’s transportation energy needs. Hydrogen combustion engines and fuel cells could benefit the environment while reducing the world’s consumption of fossil fuels. These engines work by converting hydrogen’s chemical energy into mechanical energy or through a chemical reaction between oxygen and hydrogen.
The problem with using hydrogen in transportation is that it is expensive to produce, store and transport. Now, the US Department of Energy’s Office of Nuclear Energy is working on the Nuclear Hydrogen Initiative in an effort to produce large amounts of hydrogen using nuclear energy in an economical and environmentally friendly way. This effort could give the US emissions-free, large-scale hydrogen production that would provide fuel for cars and trucks. The Nuclear Hydrogen Initiative aims to have an experimental, pilot-scale hydrogen production system in place by 2013. Critics say that the cost is insurmountable and that emission-free fuel-cell vehicles won’t be practical for many years.
Governments in other parts of the world, including Japan and Germany, are also devoting funds to building new hydrogen-powered vehicles and refueling stations. Japanese carmaker Toyota announced plans in 2009 to introduce an affordable fuel-cell car by 2015 (Japan Leads the Race for a Hydrogen Fuel-Cell Car, The Christian Science Monitor, Feb. 1, 2010).
Demand for Hydrogen
Many experts believe hydrogen is an important energy resource for the future since it is clean, abundant and can be produced from a variety of resources. However, new systems—including hydrogen production plants and refueling stations for hydrogen fuel-cell vehicles—must be designed and built before significant contributions of hydrogen can be used. This would be a very costly endeavor. If the cost and logistical obstacles can be overcome, however, and hydrogen is proven to be a feasible solution to the world’s energy needs, the demand will go up significantly.