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Hydrogen
In this page I will discuss the way hydrogen
can be produced and used as a replacement for oil and natural gas.
Hydrogen will become the fuel of choice when oil
reserves become in short supply and thus too expensive for common use. Under the
hydrogen economy, pure hydrogen will be produced, distributed, and sold as oil
is now. When this happens is not known. It appears to be on the horizon
considering that oil discoveries and reserves are not keeping up with the
world's demand. Even as oil reserves are dwindling, populous countries like
China are now demanding significant greater amounts of oil.
Consider this. mankind has only been using oil and
natural gas for about 125 years and we can see the end of these reserves. In a
millennium there will certainly be no oil remaining. Will there be a population
on the earth who lives like we do? The world will need a fuel for
transportation. Nuclear power is the only energy source I can see that will be
able to supply ample energy as far out as there will be people on this earth. I
think we should fully develop it. Otherwise there will be wars on wars to fight
for the last drop.
About 7.8 million metric tonnes (17.6 billion pounds) of
hydrogen are produced in the United States today, enough to power 20-30 million
cars or 5-8 million homes. Nearly all of this hydrogen is used by industry in
refining, treating metals, and processing foods.
At the present time there is a lot of action towards fuel-cell
automobiles. But several difficulties exist, as shown below. Fuel-cell
engines are not yet very durable. They are still very expensive, and as shown
below General Motors fuel cell engines are engineered for only a 50,000 mile
lifetime. Coupled with a short life time and a very high cost engine makes the
hydrogen fuel cell engine not yet feasible.
Also the supply of hydrogen is mainly achieved from steam reforming of
natural gas. This is not a reliable future for hydrogen supply.
Natural gas is not too plentiful in the United States and will be too expensive
if expanded usage for vehicle fuels is enacted. Moreover, hydrogen
made from hydrolysis of water is only about 60% efficient. This does not
bode well as a method to obtain hydrogen. This is especially deleterious when
using renewables, since they only have capacity factors of 20% or less.
Enabled
by GENERAL MOTORS' fourth-generation fuel cell propulsion
system, the Equinox Fuel Cell is a fully-functional crossover vehicle,
engineered for 50,000 miles of life.
Where Does Hydrogen Come From?
Hydrogen does not exist in a free chemical
state on earth. It must be extracted from either water or fossil fuels such as
oil, natural gas, or coal. The latter are hydrocarbon fuels to begin with. To
get great quantities of hydrogen, it makes no sense to take hydrogen from hydrocarbon fuels.
These fuels give off their heat through the combustion process.
The combustion of hydrogen
2 H2 + O2 → 2 H2O
produces 51,571 BTU/lb or 120,000 kJ/kg of lower heating value energy. Splitting it to get
hydrogen requires the same amount of energy. But the process of splitting it is
not 100% efficient so it requires considerably more.
There are two methods available to obtain free state
hydrogen from water, and there is a method to get hydrogen from natural
gas. :
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Electrolysis: Electrolysis is a process that
requires an electric current. The electric current is passed through a solution
of an electrolyte and hydrogen is liberated at the cathode, The efficiency of
the process is about 50%. As a result of the low efficiently it is
doubtful process.
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Thermochemical splitting water: This process does
not require an electric current, but it requires a relatively high temperature
700oC to 900oC. Heat is applied in a process called the
Sulfur-Iodine (S-I) thermochemical water cracking. It is currently under
development at EAWA ( Italy), JAERI (Japan) and elsewhere.
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Steam Methane Reforming (SMR) Steam methane
reforming accounts for 95% of the hydrogen produced in the U.S.
The process involves passing steam and methane over a
chemical catalysis in a tube and externally applying heat. It is the most
economical process as long as the price of natural gas remains relatively low,
which does not happen. It also has CO2 as a by product..
The current light water commercial nuclear reactors
cannot supply heat energy high enough in temperature for the thermochemical
process of splitting water to get hydrogen.
In any process of separating hydrogen from its
water molecule, more energy is required then is gotten back from the hydrogen
used as a fuel. But it is necessary to get fuel in a form that can be carried in a
vehicle or airplane tank as well as a pipeline for home heating and cooking.
Comparison of the electrolysis, thermochemical methods to
and SMR to produce hydrogen.
Electrolysis:
Electrolysis requires the generation of electric energy to
produce hydrogen. Water electrolysis takes place as described in most
chemistry books. Many commercial companies manufacturer electrolyzers to
carry out the process of splitting water into its components of oxygen and
hydrogen. The two step process is the following:
Electric energy generation efficiency = 35%
Electrolysis efficiency
= 50%
Combined results
0.35 x 0.50 = 17.5 %
These efficiencies are given as examples of what
they might be, recognizing that each can vary according to the individual system
efficiencies.
Here is a
recommendation from the US Department of Energy (DOE).
The Department of
Energy’s multi-year research, development, and demonstration plan should address
how best to partner with industry to create robust, efficient, and
cost-effective wind-electrolysis-hydrogen systems that will be ready for
deployment as the distributed hydrogen infrastructure begins to develop. This is
particularly important as there needs to be a research and development emphasis
on optimizing wind-electrolysis-hydrogen
My
comment: Wind power operates in the US at only a capacity factor of about 20%.
Wind will never produce a significant about of hydrogen. Why commit a lot of
money trying to develop wind power to produce hydrogen? And distributed
wind-hydrogen refueling stations? The wind site would take much to much area at
each location. And the sites for refueling stations are not usually windy
locations.
Thermochemical:
The Thermochemical process is in a development state. The
high temperature heat output from a nuclear
reactor can be generated without going through a heat to work cycle. In
thermodynamic terms the heat energy is not diminished by the Carnot Cycle
efficiency. More information about this subject can be obtained from the report Efficiency of hydrogen
production system using alternative nuclear energy technologies, By
Bilge Yildiiz, and Mujid S. Kazimi, MIT nuclear engineering
department.
SMR
This is the most used process today. It supplies more than
90% of the hydrogen produced in the United States. Natural gas and steam are
heated in a tube containing a chemical catalysis. The products are hydrogen and
carbon dioxide CO2. SMR is not a desirable method to produce
hydrogen for auto hydrogen fuel or electric energy production because it uses
natural gas which is in short supply and also produces the green house gas
CO2.
Some good news, and some bad news . . .
One of the crucial limiting factors for
converting to hydrogen-powered energy now is the (primarily energy) cost of
producing hydrogen. The good news is there seems to be a way to do it
efficiently using current technology. The bad news is, it involves nuclear
power
Link:
Green Car Congress: Milestone for H2 Production by High-Temperature
Electrolysis.
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VTA
finds hydrogen buses cost much more to run than diesel vehicles The experiment
sounded so grand three years ago: The Valley Transportation Authority and
SamTrans would test three buses that run on hydrogen fuel cells, emit no
smog-inducing pollutants and help keep the valley's air clean.
Green, yes. But a new
report from the VTA says the $18 million state-mandated pilot project
costs too much green - and raises troubling questions about whether the
program should continue.
The most glaring figure:
Zero-emission buses - or ZEBs - cost $51.66 to fuel, maintain and operate
per mile compared with just $1.61 for a 40-foot conventional diesel coach.
They break down much more frequently, and replacement parts are next to
impossible to order, according to the report.
But the VTA's early results are not encouraging.
Although the cost of a new hydrogen-fuel-cell bus has fallen from about
$3.5 million to $2.5 million, a diesel coach costs about $400,000. And
ZEBs have on average traveled 1,100 miles before needing repairs in the
VTA trial, while a typical diesel bus covers about 6,000 miles.
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This is a lousy and wasteful way
to get hydrogen, but they have more natural gas then they know what to do
with so why not waste it?
Hydrogen Power Plant Plan for UAE
Jan 17 - Independent, The; London (UK) Hydrogen
Energy, a joint venture of BP and Rio Tinto, is in talks to build what would be
the world's first hydrogen power plant in the United Arab Emirates.
The $2bn (1bn) project, which is being studied by the
BP-Rio venture and Abu Dhabi Future Energy, the Government-owned alternative
energy company, is seen as a possible answer to the emirate's rapidly rising
energy needs. Demand for oil and gas in the Middle East has skyrocketed in
recent years as massive profits derived from rising oil prices - Brent crude
closed yesterday at $88.72 per barrel - has fuelled a construction boom.
The hydrogen power plant, which converts natural gas
into hydrogen that can be burned to generate power while the resulting
carbon dioxide is pumped underground using carbon capture and sequestration
technology, would be the first of its kind in the world. It could produce up to
7 per cent of the power needs of the emirate, which is expected to announce
Hydrogen Energy as its partner next week
Hydrogen is difficult to deliver
The government's comments about
hydrogen delivery are the following:
Hydrogen has physical properties that may cause
embrittlement of some high-strength steel piping materials and components such
as compressors and valves that are commonly used today to transport natural gas.
Even if these problems could be overcome, today's natural gas pipelines may not
be available or capable of handling the additional volumes of hydrogen
projected. Therefore, it is likely that significant capital investments in a
dedicated hydrogen delivery infrastructure will be required before a hydrogen
economy is practicable.
My comment: This means that the
hydrogen electrolyzers to convert water to hydrogen by electric energy should be
located on the refueling sites.
Thermo to hydrogen overall efficiency using Modular High
temperature gas cooled reactor (MHR-ST)
50% with the reactor temperature of 850 C (
1,562 F)
The comparison of these two are quite revealing in that
the Thermochemical conversion of generated heat or electric energy strongly
favors the Thermochemical process. As usual, the advantages are encumbered by
much more difficult to construct high temperature gas cooled reactor system.
Of course the generation of electric energy by wind or
solar does not suffer the Carnot Cycle efficiency, but I do not believe that
either of these methods could generate enough electric energy to operate our
transportation fleets. And the cost of electric energy from the renewables is
too high.
Equivalent cost of hydrogen
energy to
a gallon of gasoline using electrolysis of water at 50% efficiency
| Energy Source |
Cost per kWh
|
Equivalent cost of a
gallon of gasoline* |
| Nuclear, Coal, Hydro |
$0.033 |
$2.38 |
| Wind |
$0.07 |
$10.69 |
| Solar Trough |
$0.17 |
$12.24 |
| Solar PV |
$0.24 |
$16.54 |
* This cost information does not include the state and
federal taxes.
It is obvious that reliance on wind or solar
trough, solar PV's to energize a hydrogen refueling station is not a wise
choice.
Here is the
California Fuel Cell Partnership (CAFCP)
explanation of where hydrogen comes from.
Where does hydrogen come from?
Hydrogen is the most abundant element in the universe, and
can be found in water, fossil fuels and other sources. It bonds with other
elements to form commonly known molecules such as water, methane (natural gas)
and methanol. Hydrogen is produced by unlocking the chemical bonds in the
molecules that form these substances. The water molecule (H 20), for example,
consists of two hydrogen atoms bonded to an oxygen atom. One way to produce
hydrogen is to break water apart through a process called electrolysis. In this
process, electricity is used in the presence of a catalyst to separate the
hydrogen from the oxygen in the water. Another approach is to liberate the
hydrogen by "reforming" fuels such as natural gas, gasoline or methanol.
Currently, our members are exploring many options for producing hydrogen.
My comments: Liberating hydrogen from
reforming fuels such as natural gas, gasoline, and methanol is wasteful. These
fuels are expensive to get in the first place and are in short supply. To reform
them further reduces the energy yield of these items. They did not say what
many options their members are exploring to produce hydrogen. At a meeting I
attended they emphatically ruled out the nuclear option. I suspect they
intend renewables as the energy source to provide hydrogen. Of course
renewables will not begin provide a significant energy base for transportation
vehicles.
The CAFPC considers it a major accomplishment
when they get a lot of people showing up to ride in fuel cell powered autos.
Nuclear Reactors Will Produce
the Hydrogen
To those in the know, "hydrogen economy" has always meant
nuclear power. The idea dates from the early 1970's and was developed by
engineers; it goes like this. We're running out of oil, but breeder reactors
will give us almost unlimited, cheap nuclear power. The problem is that nukes
make electricity, which is not so good for cars, trucks airplanes etc. So lets
make hydrogen with nuclear power and have hydrogen cars. In 1973, Scientific
American published this plan for "Freedom CAR."
What Are the economics of nuclear
power to produce hydrogen?
The passage below was taken from the Report:
"The Economic Future of Nuclear Power" by the
University of Chicago, August 2004.
This study reviews the prospects of hydrogen as a
transportation fuel that would reduce U. S. dependence on foreign oil and have potentially large environmental benefits. Mass production costs need to be
reduced by roughly one-half to two-thirds to achieve widespread adoption of
hydrogen.
The environmental benefits of hydrogen would
be tempered if fossil fuels, with their attendant carbon
emissions, were used to produce the hydrogen. Carbon emissions from oil would
then simply be replaced by emissions from fossil-fuel power generation or steam
methane reforming.
Nuclear energy, on the other hand, would
provide a pollution-free input to hydrogen production. A hydrogen economy,
accompanied by more stringent control of carbon emissions, could greatly expand
the demand for nuclear power.
A Future Nuclear Power Plant for
Hydrogen Production.
Below is a is a published paper by a group of
scientists from the US and abroad. The paper describes a nuclear reactor plant
which has the ability to provide hydrogen for the worlds future energy needs.
This concept will be necessary some day when oil and natural gas reserves no
longer meet the energy needs of the US and the world as well. It is a concept we
should have started yesterday to get a leg up in the problem.
A PROPOSED MODULAR-SIZED. INTEGRATED
NUCLEAR
AND
HYDROGEN-BASED ENERGY SUPPLY-CARRIER
SYSTEM
Bruce W. Spencer, Richard D. Doctor, and David C.
Wade, Argonne National Laboratory
Prof. Kenneth Lee Peddicord Texas A&M University
Mr. Charles Boardman, General Electric Company
Dr. Giuseppe Marucci, ENEA (Italy)
Motivation and Overview
The goals of the proposed concept are to
achieve an expanded role for nuclear energy; to extend its applicability into
the non-electric two-thirds of the primary energy market; and to provide a
sustainable global energy supply architecture with fission generated heat
coupled to those modern energy converters (gas turbines and fuel cells) that
will already be in widespread use in the decades following 2020.
Abstract:
A system is proposed for the utilization of
nuclear energy to produce hydrogen, electricity, potable water and other
marketable resources in a self-contained, modular plant featuring zero carbon
emissions. The reference process for hydrogen production (and oxygen byproduct)
is the Sulfur-Iodine thermochemical water cracking cycle. This cycle requires
process heat at up to 900 C temperature which is provided by a fast neutron
spectrum, heavy liquid metal cooled converter reactor designed for near
autonomous operation during a 15-year refueling interval. The reactor is
radically simplified and of modular construction for economic competitiveness,
and is additionally designed for proliferation resistance and passive safety. It
features maximum fission conversion of fuel, and operating lifetime, minimum
waste. The reactor heats a gaseous heat transport medium for operation of the
water cracking cycle, The waste heat is used for desalinization and process
heating. The potable water produced is used for local consumption and to feed
the water cracking process. A fraction of the hydrogen and oxygen products of
this process are used to power a combustion turbine cycle for high efficiency
base or load-following electricity generation. The main portion of the hydrogen
is available to power fuel cells envisioned to be used in the transportation
sector.
A DOE planned Electric Power and
Hydrogen Production System for the Future
The Generation IV Roadmap identified reactor
system concepts for producing electricity and hydrogen that excelled at meeting
the goals of superior economics, safety, sustainability, proliferation
resistance, and physical security.
One of these reactor system concepts, the Very
High Temperature Gas Cooled Reactor System (VHTR), is also uniquely suited for
producing hydrogen without the consumption of fossil fuels or the emission of
greenhouse gases.
DOE has selected this system for the Next
Generation Nuclear Power (NGNP) Project, a project to demonstrate emissions-free
nuclear-assisted electricity and hydrogen production by 2017.
Another View By ROBERT F. KENNEDY
Jr.
Robert F. Kennedy Jr. is a lawyer for the Natural
Resources Defense Council. He stated the following:
Here's why the environmental community isn't
ecstatic over President Bush's call to spend more than $1 billion over five
years to develop a hydrogen-powered car to wean us from our addiction to Middle
East oil. Certainly, fuel cells that use renewable resources like wind and solar
power to extract hydrogen from water promise America a safe, clean energy
solution. However, in a SOP (standard operating procedure) to the energy
industry, the White House wants to extract hydrogen instead from coal and
natural gas (without controlling carbon emissions), thereby increasing global
warming and fouling our landscape. Worse, the president wants to build a new
generation of nuclear power plants specifically for hydrogen production.
My comments:
This is the same Robert Kennedy
Jr. who preaches conservation and renewables, and then flies around the country
in his private jet and rails against the 130 unit wind turbine installation
proposed for installation off
the coast of Martha's Vineyard where he lives. Along with John Kerry, they don't
want a wind farm in their back yard. The Kennedy's live abundantly off of
old Joe Kennedy's ill gotten gains, but they want us to conserve and live like
paupers.
It is not possible to take the environmentalist's proposals seriously that
wind and solar can produce hydrogen to power even a single city. No
conceivable mix of solar and wind could adequately produce electric energy and
hydrogen quantities sufficient for our transportation vehicles.
Epilogue
Now if we can keep the Democrats
out of the presidency long enough so they will not be able to scratch the
progress of nuclear power hydrogen/electric energy production systems as payback
to the environmentalists, we can make real progress. This my friends will wean
us from Mideast oil.
Throughout this web Site it can be
seen that everyone including the religions and environmentalists talk about the
fuel cell-hydrogen system holding the future to our energy supply. However, the
method of procuring hydrogen as a fuel has been left out. Also I believe
that hydrogen should be not be obtained from fossil fuels. These are not capable
of fulfilling the worlds long term energy supply.
Over time the proposed
nuclear-driven energy supply architecture would displace fossil and provide
energy to support a global energy infrastructure meeting all aspects of
sustainable development - secure longevity, ecological compatibility and social
acceptability. With concomitant institutional innovation it might succeed to
fuel an increase in GDP/capital for the 80% of humanity which was not reached by
the Industrial Revolution. [1]
REFERENCE [1] G. Bruntland,
Chairman, World Commission on Environment and Development, (1987), Our Common
Future (The Bruntland Report), Oxford University Press, Oxford, United Kingdom.
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