Revisiting hydrogen - Wayne State University

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Revisiting hydrogen
Marilyn Radler
Oil & Gas Journal, January 17, 2005 – Page 15.
More than a year ago in this column, this editor wrote about the push for research into the deployment of
hydrogen technologies, fuel cells, and hybrid-vehicle technologies (OGJ, July 7, 2003, p. 15).
The conclusion was then, and remains now, that any widespread use of such technology would not occur in
the near future, nor would there soon be a significant decrease in the use of fossil fuels for transportation.
A study released last month from the Cato Institute says that renewable energy sources will not relieve the
US of its dependence on foreign sources of energy any time soon. Moreover, in this study, Donald Anthrop,
professor emeritus of environmental studies at San Jose State University, says that the transition toward
hydrogen-powered fuel cells from gasoline would greatly increase total US energy consumption even if the
hydrogen were extracted from water rather than from fossil fuels.
In addition to federal programs to underwrite research of hydrogen-powered fuel cells, the governor of
California is promoting the use of state funds to begin building a network of hydrogen refueling stations
across the state. The reasoning behind these moves is that if the stations and the technology are in place,
automakers will manufacture fuel cell-powered vehicles and consumers will buy them.
While advocates of hydrogen-powered fuel cell technologies concede that their appreciable penetration of
the market is at least several decades away because of cost considerations, Anthrop notes that these
proponents disregard the environmental costs of the technology. He says that harnessing hydrogen for
widespread use in the energy sector will require more energy than it will save, and it will worsen rather than
improve environmental quality.
Producing hydrogen
In the Cato paper, the professor looks at two methods of producing hydrogen: electrolysis and steam
reforming. He says that environmentalists often cite the electrolysis method as a viable and attractive way to
reduce greenhouse gas emissions. But he calculates that one must put 140.8 kw-hr of energy into the front
end of a coal-fired power plant with a typical overall efficiency of 40% to produce 17.4 kw-hr of electricity
from a hydrogen-powered fuel cell in an automobile.
Also by Anthrop's calculations, using the steam reforming method to produce hydrogen, which involves
mixing steam and natural gas and then heating the mixture in a reforming tank, would produce less energy
than if the natural gas were burned in a generating plant. Of course additional inputs are required to
generate the steam, heat the reformer tank, and separate the products in this method.
The professor asserts that powering all of the automobiles in the US by the steam reforming method would
require an increase in US natural gas consumption of about 66%. This would have big economic
ramifications, driving up the price of gas and impacting US economic growth. Also, a large percentage of
such masses of gas would likely be imported as LNG from the gas-rich Middle East.
Environmental costs
Concerned with the environmental implications of moving vehicles with hydrogen-powered fuel cells rather
than with gasoline, Anthrop figures that replacing 16 quadrillion btu (quads) of gasoline-fired energy with 32
quads of coal-fired energy to produce electrolysis hydrogen would result in a 2.7-fold increase in carbon
emissions.
Proponents of renewable energy sources argue that using alternative sources to produce hydrogen could
reduce the need for fossil fuels and net carbon emissions, but Anthrop cites problems in the use of several
renewable sources, noting that hydroelectric power plants, photovoltaic (PV) cells, and wind farms are not
ideal sources.
Hydropower generation leads all other renewable energy forms in the US but still represents a small part of
the energy mix. Plus, Anthrop cites the mounting public pressure to remove existing dams, so it's unlikely
there will be construction of new hydroelectric power generation capacity in the US.
PV cells, which are used to produce solar power, convert little of the solar radiation that strikes their panels
into electrical energy. The professor says that the energy required to make a PV panel will exceed the
energy produced by the fuel cells that come from it. Also, costs of this type of energy would be prohibitive.
Wind power facilities are capital-intensive, and the power generated by them is only intermittently available,
Anthrop adds.
Anthrop concludes that the marketplace and private investors, rather than government, will best judge the
merits of emerging technologies.
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