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Hydrogen as an energy source. Hydrogen for use as a chemical energy source (fuel cells, combustion, etc.) is not a source of energy. The hydrogen “economy” does not refer to a new source of energy. Do not confuse the concept of an energy source with the concept of energy usage. Here.
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Hydrogen as an energy source Hydrogen for use as a chemical energy source (fuel cells, combustion, etc.) is not a source of energy. The hydrogen “economy” does not refer to a new source of energy. Do not confuse the concept of an energy source with the concept of energy usage.
Here Where is the energy stored? Not here H2O
What makes the light? Courtesy of Princeton Plasma Physics Laboratory http://www.pppl.gov/fusion_basics/pages/fusion_energy.html
Hydrogen fuel drives the lamps of the universe -The universe, and the solar system, is more than 90% hydrogen -The sun burns hydrogen: that’s why it shines -The burning is “nuclear”: nuclei of hydrogen are fused to form helium with a large release of energy -By the way, this process goes on and on and eventually builds all the elements, and that’s why we are what we are today, but this is a different issue……
How does the lamp light? A chain of nuclear fusion reactions: The gas “fell” together until the temperature rose to about 15 million degrees C, at which the nuclear fuel began to “burn”: Two protons fuse to make deuterium plus a (positive) electron (plus a neutrino). This takes several billion years on the average, but fortunately there are lots of protons trying it at any time. The deuterium nuclei now fuse, in a two step process to make helium nuclei, releasing about 20 MeV of energy.
p + p > d + positive electron + neutrino Process on the average take several billion years
How does the lamp light? A chain of nuclear fusion reactions: The gas “fell” together until the temperature rose to about 15 million degrees C, at which the nuclear fuel began to “burn”: Two protons fuse to make deuterium plus a (positive) electron (plus a neutrino). This takes several billion years on the average, but fortunately there are lots of protons trying it at any time. The deuterium nuclei now fuse, in a two step process to make helium nuclei, releasing about 20 MeV of energy.
Can we burn hydrogen in nuclear furnaces on the surface of the earth? • What is the fuel? hydrogen (deuterium) in water • The problem: to get the hydrogen nuclei close to each other requires a very high “ignition” temperature, millions of degrees centigrade. Furnaces melt. • The solution: - Large “plasma” devices contain the gas in magnetic bottles (MFE) - Intertial confinement: make little controlled nuclear bombs (ICF)
Deuterium/tritium fusion deuterium fuses with tritium releasing a helium nucleus and a neutron plus 18.3 Mev of energy Per F. Peterson, Professor, University of California, Berkeley http://www.nuc.berkeley.edu/thyd/icf/DT_fusion.html
Comparison to coal Courtesy of Princeton Plasma Physics Laboratory http://www.pppl.gov/fusion_basics/pages/fusion_energy.html
Magnetic confinement today: ITER (the way) http://www.iter.org/ $5-10 B 500 Mw of power Run in 2013 Run for 20 years Demonstrate that can produce this kind of power No power extraction Will use external tritium Will serve as basis for serious power plant design.
Proposed Sites Rokkasho-mura, Japan Cadarache, France
A few facts on politics • Idea started in 1985,US, Soviet Union, Europe, Japan • The US withdrew, then rejoined in 2003 • Last month Canada withdrew • Two sites in Japan and France are the main candidates. Recent meeting to choose disintegrated in accusations (2004).
Inertial Confinement http://www.llnl.gov/nif/library/ife.pdf
Inertial Confinement http://www.llnl.gov/nif/library/ife.pdf
Radioactivity? but… http://www.llnl.gov/nif/library/ife.pdf
Economics of ICF http://www.llnl.gov/nif/library/ife.pdf
Inertial Confinement:NIF http://www.llnl.gov/nif/nif.html
Inertial Confinement:NIF http://www.llnl.gov/nif/nif.html
NIF objectives • To obtain fusion ignition in the laboratory • Stockpile stewardship: how to study hot plasma • High energy density science
Where are we with NIF? • The National Nuclear Security Administration's (NNSA) National Ignition Facility (NIF) at Lawrence Livermore National Laboratory reached a major milestone this week in activating the first four of its 192 laser beams. Starting the week of Dec 9, scientists and engineers powered up the laser beams in a series of increasing energy test runs. At the end of this series of shots these four laser beams generated at total of over 43 kilojoules of infrared light in a pulse lasting five-billionths of a second. This corresponds to a power level of over 8 thousand billion watts (8 terawatts), which is about 10 times more power than the entire US electrical generating capacity, but only lasting 5-billionths of a second. The energy contained in the 43 kilojoule pulse is equivalent to a 1 ton automobile traveling at about 20 miles per hour.
Summary • Hydrogen is not a chemical source of energy. It is possibly very useful as a (stop gap) medium for storage and transfer, but does nor remove the need for a source, such as coal, gas, oil, … • Hydrogen (deuterium) as a nuclear fuel is plentiful and abundant. But nobody knows how to make the furnace. Probably energy source on century time scale. Will we make it?
Inertial Confinement http://www.llnl.gov/nif/library/ife.pdf
Whats new by BOB PARK (APS)
Whats new by BOB PARK (APS)