Fusion and ITER Flashcards
The ITER Members—
Seven
China, the European Union, India, Japan, Korea, Russia the United States
ITER
I
T
E
R
International
Thermonuclear
Experimental
Reactor
ITER
Additional meaning
“The Way” in Latin
Where is ITER
Saint Paul-lez-Durance, southern France.
The world record for fusion power to date?
Date
Who
Q=
MW
In 1997 the European tokamak JET produced 16 MW of fusion power from a total input power of 24 MW (Q=0.67).
Record for Longest Tokamak Runtime
Plasma containment without fusion
Date, who
With fusion
Date, who
Without fusion, in tokamaks, the longest runtime is 29 hours, set by the fusion startup Tokamak Energy on July 6, 2016.
The record with fusion is 11 ms and was set by the fusion startup Tri Alpha Energy in 2015.
JET
J
E
T
Joint European Torus
ITER
Q=
MW
ITER is designed to produce a ten-fold return on energy (Q=10)
500 MW of fusion power from 50 MW of input power.
FUSION
Three conditions for fusion in a lab?
Three conditions must be fulfilled to achieve fusion in a laboratory
- very very high temperature
- sufficient plasma particle density (to increase the likelihood that collisions do occur)
- and sufficient confinement time (to hold the plasma, which has a propensity to expand, within a defined volume).
Sun Fusion Temperature
In the Sun’s core temperatures reach 15,000,000 °C
In the sun, where does the energy come from?
what percent of the mass is released as energy?
In the fusion of two hydrogen nuclei to form helium, 0.7% of the mass is carried away in the form of kinetic energy of an alpha particle or other forms of energy, such as electromagnetic radiation.
temperature needed for fusion in a lab?
150,000,000° Celsius)
Word origin of ‘tokamak’
from Russian
to(roidál’naya)
kám(era s)
ak(siál’nym magnitnym pólem),
ie. toroidal chamber with magnetic field
What is a Plasma?
At extreme temperatures, electrons are separated from nuclei and a gas becomes a plasma—often referred to as the fourth state of matter. Fusion plasmas provide the environment in which light elements can fuse and yield energy.
Who pays how much for ITER?
Europe is responsible for the largest portion of construction costs (45.6 percent); the remainder is shared equally by China, India, Japan, Korea, Russia and the US (9.1 percent each). The Members deliver very little monetary contribution to the project: instead, nine-tenths of contributions will be delivered to the ITER Organization in the form of completed components, systems or buildings.
Two other contributors to ITER
Names
Dates
The ITER Organization has also concluded non-Member technical cooperation agreements with Australia (through the Australian Nuclear Science and Technology Organisation, ANSTO, in 2016) and Kazakhstan (through Kazakhstan’s National Nuclear Centre in 2017).
ITER non-Member technical cooperation agreements.
Define
Enables this country access to research results of ITER in exchange for construction of selected parts of ITER machine.
When is ITER’s First Plasma scheduled
ITER’s First Plasma is scheduled for December 2025.
That will be the first time the machine is powered on,
Fusion compared to
Coal
Fission
terms of sheer scale, the energy potential of the fusion reaction is superior to all other energy sources that we know on Earth. Fusing atoms together in a controlled way releases nearly four million times more energy than a chemical reaction such as the burning of coal, oil or gas and four times more than nuclear fission.
ITER
How is the energy utilised?
The helium nucleus carries an electric charge which will be subject to the magnetic fields of the tokamak and remain confined within the plasma, contributing to its continued heating.
However, approximately 80 percent of the energy produced is carried away from the plasma by the neutron which has no electrical charge and is therefore unaffected by magnetic fields.
The neutrons will be absorbed by the surrounding walls of the tokamak, where their kinetic energy will be transferred to the walls as heat.
Role of Lithium in Fusion
If the blanket modules surrounding the Tokamak contain lithium, a reaction occurs: the incoming neutron is absorbed by the lithium atom, which recombines into an atom of tritium and an atom of helium. The tritium can then be removed from the blanket and recycled into the plasma as fuel.
Blankets containing lithium are referred to as breeding blankets. Through them, tritium can be bred indefinitely. Once the fusion reaction is established in a tokamak, deuterium and lithium are the external fuels required to sustain it. Both of these fuels are readily available.
Tritium breeding
If the blanket modules contain lithium, a reaction occurs: the incoming neutron is absorbed by the lithium atom, which recombines into an atom of tritium and an atom of helium. The tritium can then be removed from the blanket and recycled into the plasma as fuel.
Blankets containing lithium are referred to as breeding blankets. Through them, tritium can be bred indefinitely. Once the fusion reaction is established in a tokamak, deuterium and lithium are the external fuels required to sustain it. Both of these fuels are readily available.
Tritium breeding
Why is it important?
Tritium is a fast-decaying radioelement of hydrogen which occurs only in trace quantities in nature. It can be produced during the fusion reaction through contact with lithium, however: tritium is produced, or “bred,” when neutrons escaping the plasma interact with lithium contained in the blanket wall of the tokamak.
Lithium from proven, easily extractable land-based resources would provide a stock sufficient to operate fusion power plants for more than 1,000 years. What’s more, lithium can be extracted from ocean water, where reserves are practically unlimited (enough to fulfill the world’s energy needs for ~ 6 million years).
Global inventory for tritium is presently around twenty kilos, which ITER will draw upon during its operational phase. The concept of “breeding” tritium within the fusion reaction is an important one for the future needs of a large-scale fusion power plant.
DEUTERIUM
Origin of Deuterium
Percent of Hydrogen as Deuterium
Deuterium is destroyed in the interiors of stars faster than it is produced. Other natural processes are thought to produce only an insignificant amount of deuterium. Nearly all deuterium found in nature was produced in the Big Bang 13.8 billion years ago, as the basic or primordial ratio of hydrogen-1 to deuterium (about 26 atoms of deuterium per million hydrogen atoms) has its origin from that time.
ITER Timeline
Past Milestones
- Decision to site the project in France
- Signature of the ITER Agreement
- Formal creation of the ITER Organization
2007-2009. Land clearing and levelling. (3 Yrs)
2010-2014. Ground support structure and seismic foundations for the Tokamak (5 Yrs)
