Using hydrogen technology to propel a moving object was first proposed by the Rev. W. Cecil who was a fellow at Magdalene College in Cambridge. He presented a paper in 1820 entitled, “On the Application of Hydrogen Gas to produce moving power in Machinery,” in which he discussed that when hydrogen is mixed with air, it produces a “large partial vacuum.” Then, the air that rushes back into this vacuum creates a force “nearly in the same manner as the common steam engine” (Hoffman 2002). Then, in 1923, John Burden Sanderson Aldine gave a lecture at Cambridge in which he stated that “hydrogen-derived from wind power via electrolysis, liquefied and stored, would be the fuel of the future” (Hoffman). In the 1930s, Harry Ricardo and A.F. Burst investigated the burn characteristics of hydrogen as a fuel in England (Hoffman). During World War Two, some of the greatest advancements in hydrogen fuel technology came from a German scientist, Rudolf Erin, but unfortunately due to his affiliation with the Nazi party, most of his business possessions where confiscated and many of his papers where destroyed in the Allied bombing (Hoffman). After the war, Francis T. Bacon developed a practical hydrogen-air fuel cell, which latter became important in the American space program (Hoffman). In 1962, Eduard Justi and August Winsel wrote a paper titled “Cold Combustion-Fuel Cells,” in which they laid out the idea of splitting water into its constituted parts of hydrogen and oxygen. When these elements are combined, enough energy is released to provide power, and water is re-formed (Hoffman). Also in the same year, an Australian electrochemist John Bockris proposed a plan to supply cities in the United States with solar-derived energy via hydrogen (Hoffman). In the last ten years, the development of hydrogen as a fuel has grown in leaps and bounds (see Timeline 1)
Hydrogen as a fuel is produced in six major ways: electrolysis, steam-methane reformation, biomass gasification, photoelectrolysis, coal gasification, and biohydrogen. Water electrolysis is the method of creating hydrogen in which an electrical current is passed through water to separate it into its constituents. While this method produces extremely pure hydrogen, it also uses significant amounts of electricity, which is often produced from coal or other types of power plants (Rocky Mountain Institute 2005). Also, hydrogen can be produced from methane, which is also known as natural gas. The mechanism is a two-step process at temperature of about 1000 ºC and is shown below: (Macdonald and Berry 2000)
CH4(g) + H2O(g) catalyst CO(g) + 3H2(g)
CO(g) + H2O(g) catalyst CO2(g) + H2(g)
However, this process both uses a fossil fuel as a starting material and produces carbon dioxide, a greenhouse gas, and therefore adding to the global climate change problem. Another method to produce hydrogen is by biomass gasification, in when a hydrogen-rich biomass item, such as wood chips or agricultural waste, is heated in a controlled atmosphere. This causes the biomass to convert to gaseous carbon monoxide, carbon dioxide and hydrogen. Most of the hurdles of biomass gasification have been economical, but hopefully the increased demand for hydrogen will make biomass gasification more economically viable. Hydrogen can also be produced from photoelectrolysis, which is the splitting of water into its constituents via the energy in sunlight via a semiconductor. However, this method has not been able to move from beyond the laboratory. Hydrogen can also be produced from coal though gasification, yet this undermines the idea of hydrogen as a “green” fuel, because it is being produced from a fossil fuel.
In addition to all the methods listed above, there is a method to produce hydrogen from green algae and this is known as BioHydrogen (Rocky Mountain Institute). A group led by Paul Weaver from the Nationally Renewable Energy Laboratory in Golden, Colorado, experimented with the algae Rhodospirillum rubrum, which produces hydrogen via its hydrogenase enzyme from water. Typically hydrogenase microbes are killed in the presence of oxygen, but there is a group discovered in a subset of R. rubrum that will continue to produce hydrogen even when exposed to oxygen. These microorganisms do not split water so the next step is to “take just the light-absorbing, water-splitting complex and link it directly to the hydrogen producing enzyme” (Hoffman).
What does hydrogen production mean and how can it apply to a more sustainable society? There is a philosophy called the “hydrogen economy,” that states that nations should change from an oil-based society to a society that relies on hydrogen. This “hydrogen economy would make it possible a vast redistribution of power” in which the oil companies and utilities would become obsolete. In this new economy, each human being would “become the producer as well as the consumer of his or her own energy” (Rifkin 2002). This idea is called “distributed generation” (Rifkin). Rifkin also cites access to electricity as a main contributor to economic growth and that for “every 100 household, 10 to 20 new businesses are created”(Rifkin). Also according to Stanford researches Mark Z. Jacobson, Whitney Goldsborough, Mark Colella and David M. Golden that converting currently operating automobiles from running by diesel or gasoline to hydrogen fuel-cell technology “would prevent millions of cases of respiratory illness and tens of thousands of hospitalizations annually”(“Toward a Hydrogen Economy” 2005).
However, there are challenges to this new “hydrogen” economy. The first being that the United States lacks an infrastructure for hydrogen fuel, therefore it gives the hydrogen cars a limited range. Also, as shown by the many methods of hydrogen production outlined, there are many ways to get hydrogen, nevertheless the only truly sustainable way to produce hydrogen is through either wind or solar power, where carbon dioxide and other greenhouse gases are not produced. As Americans, and stewards of creation, we need to look at the economic and environmental impact that oil has on the Earth. C. E Thomas, Vice President of Energy and Environment of Directed Technologies, Inc., was once quoted,
In economic terms, the cost of fuels dose not include the externalities of health effects due to urban air pollution, oil spills, ground water contamination, the military cost of defending oil, and, most important, the potential risks of major climate change. Put another way, society has a very high discount rate- we discount any adverse effects that occur in the future.
If the price of coal, oil, and, yes, even natural gas included a full account of externalities, then hydrogen would look much more promising overnight. If people had to pay $10/gallon for gasoline or 30 cents/[kilowatt-hour] for electricity to cover fossil fuel damages to our health and environment, then suddenly hydrogen fuel-cell vehicles and hydrogen produced by win, solar or biomass would look like a bargain. Investors would flock to hydrogen equipment manufacturers. People would convert their SUVs to run on clean-burning hydrogen derived from wind energy at only $2.50/gallon of gasoline equivalent.
A truly sustainable energy future has two attributes: no pollution or greenhouse gas emissions, no consumption of non-renewable resources. There are only two energy options that meet this sustainability goal: renewable hydrogen and fusion (quoted in Hoffman).
As we weigh the “externalities” of the cost of fuel, an energy source not based upon fossil fuels needs to be developed further by nations. There also needs to be more education about these alternative fuels to the common public. Thomas also stated,
Sustainability requires the intervention of governments. Governments alone have the responsibility of protecting the commons. Industry has no major incentive (other than public relations) to build a sustainable energy system. Their overriding objective is return on investment, and burning fossil fuels is very profitable. At best, they will sponsor renewable energy R&D or fuel-cell programs with an infinitesimally small fraction of their profits to give the appearance of preparing for a sustainable future. But most governments do not have the vision or leadership to look into the future and to implement policies that will provide for the welfare of future generations. Certainly, the US federal government is effectively paralyzed, barely able to pass all 13 appropriations bills, let alone tackle any significant societal problems. No US leader has the vision to state the need for sustainability and to follow the vision up with bold implantation programs (quoted in Hoffman).
A hydrogen economy will be our only viable and sustainable energy solution for the future and the government needs to step in to strongly encourage industry to continue to develop more sustainable solutions to the fuel situation.
Timeline 1: taken from Hoffman
Works Cited
Hoffman, Peter. 2002. Tomorrow’s Energy: Hydrogen, Fuel Cells, and the Prospect for a Cleaner Planet. The MIT Press, Cambridge, MA.
Rocky Mountain Institute.2005. “Where Dose Hydrogen Come From?”
Macdonald, Averil and Berry Martyn. 2000.Science through Hydrogen: Clean Energy for the Future. Heliocentris Energiessystemes GmnH, Berlin, Germany.
“Toward a Hydrogen Economy.” 2005. Environment 47.7: 7(1)
Rifkin, Jeremy. 2002. A Hydrogen Economy: The Power to Change the World. Los Angeles Times. Sept. 2, 2002.
written for independent study in environmental chemistry
4th November 2005
s.e.w
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