Слайд 2World’s reserves of fuel are going to be exhausted in
about 50 years. It’s also predicted that the gas and
the coal resources will be used up in about 60 and 220 years.
The demand for energy
in the world still grows.
It’s time now for mankind
to take care of next
generations and provide
them with new energy
sources which will not
damage our environment and which will be efficient. It’s time to harness the energy of stars.
Слайд 3Fusion energy...
Fusion is the process in which light nuclei fuse
together to form heavier ones, is the energy source of
stars. The sun fuses hydrogen to form helium. In that
reaction, about a half of a
percent of the hydrogen mass is
converted into energy, as described
by Einstein’s famous equation
E=mc2 , which relates mass and
energy. This energy escapes as light,
almost all of which is lost in the
depths of space. Less than one part
in a billion falls on earth, where it has sustained the water cycle, wind and life for billions of years.
Слайд 4Fusion on earth
Hydrogen atoms in the sun and stars fuse
at very high temperatures and under the extreme pressure
cause of gravity force. In principle, fusion is possible to carry out with many light elements. Among all possible reactions, the fusion of deuterium and tritium (two isotopes of hydrogen) is the easies to achieve and has been chosen to the basis for future fusion power plants.
In the process, the
deuterium and tritium
are converted into
helium and a neutron,
and a lot of energy
(about 17,6 MeV).
Слайд 5The world of plasma
Atomic nuclei repel each other, because they
both have a positive charge. To bring the nuclei close
enough together for fusion to occur, they need to collide with a very high velocity, which means that the temperature of the gas must be very high. For deuterium-tritium fusion the required temperature is in the range 100-150 million degrees centigrade. At such temperatures the atoms in the gaseous fuel lose their electrons, and together they form a “plasma” which is the fourth state of aggregation.
Слайд 6Pros of fusion energy power plants:
No CO2 emission –
greenhouse gases as we all know, changes the climate. It
causes the rise in the global temperature, changes in precipitation patterns, and a rise of the sea level. A fusion power plant doesn’t emit such gases. If the fusion programme is successful, fusion could start to contribute in the second half of century.
A sustainable energy source – safe and environmentally responsible energy source, with a Widely available and secure fuel supply. Once developed, it will have the potential to play a major role in energy production, alongside other energy generation technologies.
Слайд 7The fuel is practically inexhaustible (every cubic meter of water
contains 33 grams of deuterium, the tritium can be produced
form lithium which is one of the most abundant light metals in the earth’s crust ),
Very small amount of fuel needed - only 100 kg deuterium(from 2800 cubic meters of sea water) and 150 kg of tritium(from 10 tons of lithium ore) will be needed to operate a 1000 MW electrical power plant for one year, instead of 2700000 tons of coal during the same period.
Слайд 8No harmful radioactive emissions – primary materials for fusion (lithium
and deuterium) are not radioactive and can be transported easily.
The tritium which is the radioactive fuel component is produced inside the machine itself in a lithium-containing blanket surrounding the plasma. The neutrons released by the fusion reactions react with the lithium in the blanket, transforming it into tritium. In this way the only radioactive fuel component is both produced and burned in the machine in a closed loop. Tritium has to be transported during the start-up and decommissioning only.
Слайд 9Small amount of “ash” – inert gas helium. Exhaustive safety
studies have shown that a fusion power station can be
operated without risk of radioactive releases harmful to humans and the environment. No evacuation will be necessary beyond the area of the power station because of limited amount of tritium that could be released.
Small quantity of fuel inside and quick shutdown - the total amount of deuterium and tritium in the plasma is tiny: the weight of plasma vessel would be about the same as ten postage stamps. It could be turned off quickly – like a gas burner.
Слайд 10Fusion milestones:
Fusion research has seen enormous world-wide progress over the
past decades. Experiments on tokamaks () progressed rapidly at the
beginning of 70’s, which allowed the planning of first deuterium–tritium experiments. Achievements:
-1991, controlled deuterium-tritium in JET (The Joint European Torus, near Oxford, UK) fusion reactions were achieved for the first time on earth, releasing a fusion power of 1.7 MW.
-1994 tokamak TFTR – up to 10 MW of fusion energy
1997- JET, fusion lasted for a few seconds, 16 MW of energy
Iter project, Demo project