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NUCLEAR FUSION- POWER TO THE FUTURE
Riya Ashar ([email protected])
Why We Should Develop a New Source of Energy
One of the biggest global challenges we are
currently facing right now is global warming. The
atmospheric temperature has risen approximately 1.5
degrees Fahrenheit in the last two hundred years, with the
biggest increase being in the last fifty years. One reason
that it is increasing is because of the amount of CO2 that is
being expelled in the air is increasing. The main source of
CO2 in the atmosphere is the production of electricity.
According to the U.S. Energy Information Administration
approximately 71 percent of the CO2 in the air is from coal
powered plants, and about 33 percent of electricity is
produced coal powered plants [1], which means if we
completely cut coal fired plants from a method of
electricity production we could cause a lot less CO2 to be
released into the atmosphere causing the temperature to
stop increase. That is why scientist, environmentalists,
engineering, and many other professions are trying to find
another way to produce energy without all the negative
consequences of a coal powered plants. One method that is
being heavily research right now is nuclear fusion.
Many professionals are looking into trying to
harness the power of an atom because they contain large
amounts of energy even though they are so small. People
are looking in nuclear fusion because there are negative
impacts of all the types of energies, and they are hoping
that nuclear fusion has less negative impacts that the other
types of energy. For example, nuclear energy (fission
based) produces about 19.5 percent of United States
energy, according to US Nuclear Power Plants Institution
[2], but there are negative consequences to it, such as what
to do with the radioactive uranium that is left over after the
reaction and mining of the uranium. Another example is
solar energy which is very efficient and they costly.
According to Northwestern University solar panels run at
an average of 14 percent efficiency, and they are not very
useful during different times of the days, and parts of the
year [3]. Solar panels do not produce much electricity
during night because there is a considerably less amount of
UV in the air, and during winter because it is generally
University of Pittsburgh
11.2.2016
darker. Another energy source is wind, which also in not
very reliable because the wind varies and it is not a constant
energy. That is why fusion energy would be a very good
source because unlike fission based there is no mining
required for uranium and there are no toxic products
produced from the reaction.
After about ten years of research on nuclear
fusion, scientists in Germany have developed a specific
type of nuclear fusion reactor called the Stellarator
specifically the Wendelstein 7-X. There are different types
of fusion reactors including the Tokomak, and dyromak,
but the newest one is currently the Stellarator. Scientist are
calling the stellarator the “black horse” of nuclear reactors
according to Science Mag [4]
I have always been interested in the environment
and last year I took environmental studies in my high
school and I learned how global warming and CO2 affects
everyone and everything in the world because of the
horrible consequences of it produces, so I think it is crucial
that we find a source of energy that has the ability to
produce as much energy as a coal powered plant, but does
not have as many negative consequences to it. I know I
want my great great children to be able to see a real polar
bear, but with the speed the ice is melting because the
global temperature is rising polar bears are expected to
become extinct within the next 50 years.
History of Nuclear Fusion and Stellarators
According to Princeton Plasma and Physics
Laboratory magneic fusion research began in 1951 by
Professor of Astronomy Lyman Spitzer, Jr. He had been
involved in studying rarefied gases in space, and got the
idea from the energy of the sun. He came up with the idea
of the stellarator, which got approved by the Atomic
Energy Commission in Washington [5]. Unfortunately, the
stellarator were abandoned because scientists developed a
new type of fusion machine called tokamak. The reason the
stellarator was abandoned according to ITER was because
stellarator plasmas are driven by very complex
mathematics, and back in the 1960s when they were being
developed the tokamak seemed like it was less complex,
Riya Ashar
until around the 1990s people were having problems with
the concept with the tokamak so the stellarator came back
into the picture.
How Nuclear Fusion and the Stellarator Would
Reduce the Amount of CO2 in the Air
In a fusion reaction, a large amount of energy is
released when two light atomic nuclei are fused together to
form one heavier atom. This is also the process that
provides the energy powering the Sun and other stars. To
achive fusion in a reactor two types of hydrogen deuterium and tritium must be heated to temperatures over
100 million degrees Celsius, to form ions. When the ions
collide they fuse together generating energy in the process.
One of the hard parts about produing the energy is that
when the ions have a lot of energy they move very fast and
they hit the side of the walls and cause the ions to lose their
energy, which is why they are held in by a magnetic cage.
A current-carrying wire is wound around a tube which
creates a straight magnetic field down the center of the tube
that draws the ions away from the wall.[6]. If scientist
develop a way to produce energy from fusion we could
reduce the amount of CO2 in the air because fusion does
not produce any CO2.
hydrogen without any fusion reaction. In the later phase of
the WX-7 starting in 2019 they will attempt to use
deuterium and tritium to actually get a fusion reaction.
Eventually, the scientists at Max Planck’s Institute for
Plasma Physics want the WX-7 to be able to produce
energy, but for right now they need to perfect the system
before they can actually produce any energy from it [7].
Conclusion
The earth is currently rising in temperature very fast
because of the greenhouse effect of CO2. A lot of the CO2
in the atmosphere is from the production of electricity from
coal. That is why I think is necessary for scientist to
develop a new source of energy that produces as much
electricity as coal, but does not have as many negative
consequences to it. That is why scientist,
environmentalists, physicists, engineers, and many other
professions are trying to harness the power of atoms. If this
technology eventually works it could potential change the
world, because everything is being affected in the changing
of the temperature.
Nuclear fusion produces energy from combing
two atoms together, as the sun does. It requires a very hot
temperature to turn the atoms into plasma. Once the atoms
turn into plasma they collide with other plasma causing a
lot of energy to be expelled. Nuclear fusion is better than
other sources because it does not produce toxic waste like
nuclear fission does, theoretically it should run at a very
high efficiency rate. Unfortunately, it will take some time
for Stellarators to actually produce energy because they are
still at the initial testing phase of it have no stellarator has
produce electricity from it including the WX-7 located in
Germany. Scientist view the WX-7 as having a lot of
potential, but we will not really know until they start
producing energy which will still take a few years.
Why the Stellarator is better than the Tokamak
Stellarators use a different type of system to
produce nuclear fusion. While Stellarators produce energy
for about 30 minutes, tokamars produce pulses of energy
that last about five minutes. This is a lot less efficient
because you continuously have to produce a reaction.
Another advantage of the stellarator to the tokamaks is that
the plasma is in a much steadier state, and the likelihood of
disruptions is a lot less likely, because there is no current
in the plasma. The main disadvantage to the stellarator is
that the coil system needed to generate the magnetic field
is much more complicated and harder to build. Another
disadvantage is that the stellarators need to be very large
because the curved coils needed for the reaction [8].
Sources
[1] E.I.A. “How Much of U.S. Carbon Dioxide Emissions
Are Associated with Electricity Generation” 2015.
Accessed 10.27.2016.
http://www.eia.gov/tools/faqs/faq.cfm?id=77&t=11
Stellarator WX- 7 Located in Germany
After eighteen years of building, more than a
million hours of assembly, and about one billion Euros, the
main assembly was completed. On December 10th, 2015
the first helium plasma was produced in the WX-7 at the
Max Planck Institute for Plasma Physics. The operating
team put the magnetic field to 2.5 Tesla and initiated the
computer-controlled experiment. They put about one
milligram of gas into the evacuated plasma vessel and
turned on the microwave heating for a short 1.3 megawatt
pulse. Currently, the WX-7 Stellarator only confines
[2] N.E.I. “US Nuclear Power Plants”. 2015. Access
10.29.2016
http://www.nei.org/KnowledgeCenter/Nuclear-Statistics/US-Nuclear-Power-Plants
[3] Northwestern. “Power System”. 5.18.2015. Accessed
10.27.206
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Riya Ashar
[4] Science. “The Bizarre Reactor that Might Save Nuclear
Fusion.
10.21.2015.
Accessed
10.28.2016
http://www.sciencemag.org/news/2015/10/bizarrereactor-might-save-nuclear-fusion
[5] Princeton Plasma Physics Laboratory. “History”. 2016.
Accessed 10.29.2016. http://www.pppl.gov/about/history
[6] Culham Centre Fusion Energy. “How Fusion Works”.
2012.
Accessed
10.29.2016.
http://www.ccfe.ac.uk/How_fusion_works.aspx
[7] Thomas Rummel, Beate Kemnitz, Thomas Klinger.
“First Plasma in the Superconducting Fusion Device
Wendelstein 7-X”. 1.2016. Accessed 10.29.2016.
http://snf.ieeecsc.org/sites/ieeecsc.org/files/HP104_Rum
melTh_First%20plasma%20in%20W7-X_012016B.pdf
[8] P. Helander, C.D. Beidler, T.M. Bird. “Stellarator and
Tokamak Plasma: a Comparison. 11.21.2012. Accessed
10.28.2016.
http://www.physics.ucla.edu/~jenko/PAPERS/PPCF124009.pdf
Additional Sources
[9] Jessica Orwig. “Germany’s about to Switch on a
Revolutionary Nuclear Fusion Machine”. 11.1.2015.
Accessed 10.28.22016
[10] Alexander Hellemans. “Fusion Stellarator
Wendelstein 7-X Fires up for Real”. 2.3.2016. Accessed
10.30.2016
http://spectrum.ieee.org/energywise/energy/nuclear/wend
elstein-7x-really-starts-up
[11] ITER. “The Stellarator Renaissance”. 4.15.2012.
Accessed
10.30.2016
https://www.iter.org/newsline/172/680
[12] Alexander Hellemans. “Fusion Stellarator Starts Up”.
5.21.2014.
Accessed
10.30.2016.
http://spectrum.ieee.org/energy/nuclear/fusion-stellaratorstarts-up
Acknowledgements
One person I would like to thank is my grandfather
because without him I would not have had a laptop to
write this on because mine broke. I would also like to
thank the artists Elliphant for her good music which got
me pumped to write my essay. I would additional like to
thank my friend Julie for helping me come up with an
idea for my paper. And lastly, I would like to thank Twix
bars because that is the only thing I eat when I have to
write an essay.
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