NUCLEAR FUSION - SCIENCE AND TECHNOLOGY
News: Explained
| Why fusion could be a clean-energy breakthrough
What's in the news?
● U.S.
researchers announced a historic nuclear fusion breakthrough that could pave
the way for alternative clean energy sources.
● The
Lawrence Livermore National Laboratory
(LLNL) said an experiment it conducted this month “produced more energy
from fusion than the laser energy used to drive it”.
Key takeaways:
● The
U.S. Department of Energy described the achievement of fusion ignition as a
“major scientific breakthrough” that will lead to “advancements in national
defense and the future of clean power.”
● LLNL
director Dr. Kim Budil described it as “one of the most significant scientific
challenges ever tackled by humanity.”
● Scientists
have been working for decades to develop nuclear fusion - touted by its
supporters as a clean, abundant and safe source of energy that could eventually
allow humanity to break its dependence on the fossil fuels driving a global
climate crisis.
What is nuclear fusion?
● The
reaction happens when two light nuclei
merge to form a single heavier nucleus.
● Because
the total mass of that single nucleus is less than the mass of the two original
nuclei, the leftover mass is energy that
is released in the process.
● In
the case of the sun, its intense
heat - millions of degrees Celsius and the pressure exerted by its gravity
allow atoms that would otherwise repel each other to fuse.
Experiments of Nuclear Fusion:
● Scientists
have long understood how nuclear fusion has worked and have been trying to
duplicate the process on Earth as far back as the 1930s.
● Current
efforts focus on fusing a pair of
hydrogen isotopes - deuterium and tritium, the particular combination releases
“much more energy than most fusion reactions” and requires less heat to do so.
Significance:
● Nuclear
fusion offers the possibility of “basically
unlimited” fuel if the technology can be made commercially viable.
● The
elements needed are available in
seawater.
● It's
also a process that doesn't produce the
radioactive waste of nuclear fission.
Tokamak:
● The
scientists have tried to recreate nuclear fusion involving what's called a tokamak - a doughnut-shaped vacuum
chamber that uses powerful magnets to turn fuel into a superheated plasma
(between 150 million and 300 million degrees Celsius) where fusion may occur.