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Sustainable high-temperature plasma is what we need to create fusion as an energy source. Current fusion processes rely on pulsing a very short instant of high

by NamTaf 8y ago

Sustainable high-temperature plasma is what we need to create fusion as an energy source. Current fusion processes rely on pulsing a very short instant of high temperature. This creates a brief instance of fusion, but takes heaps more energy than that quick moment of fusion releases. Thus, it's a net negative of energy. One way to do this that the US uses for nuclear weapons research is to zap a small bit of gas with a tonne of high energy lasers all at the same instant. A high temperature plasma represents a continuous supply of fusing atoms. The current research at ITER, this place, etc. are attempts to create a persistent environment for fusion. If they can do that, then it creates an environment where research can focus on 1) reduce the energy required to hold it at that temperature (which includes limiting how much plasma leaks out, since leaking plasma drops the temperature), and 2) work out ways to extract the energy created by fusion. As I understand (and I could be wrong, it's been years since I last read about it), ITER plans to generate a net-negative energy situation (i.e. it'll never produce energy, just consume it) but hopes to create a sustainable plasma field at temperatures that cause fusion.

zaarn 8y ago
ITER will never produce electric energy but they plan to achieve Q=5, ie, output 5 times more energy than put in. The more important work on ITER is work around enabling actual power stations using Q=5 and developing the tech to maintain operating fusion reactors (remote robots, etc.)
- therein 8y ago
  At that point can't you just store the output current in supercapacitors for later use anyway? You can even feed it into the machine itself. Supercapacitors easily have better than 20% efficiency for each cycle.
  - zaarn 8y ago
    No, ITER doesn't have any planned way to make electricity, the power it outputs will be largely thermal and radiative. Engineers will likely put up a cooling system to measure the thermal output, especially after putting up the various ways to turn the major neutron radiation into heat (which is a fun way to produce energy with rare materials as a byproduct). DEMO, to my knowledge, will then include an actual electric generator to be hooked up to the fusion core.

by NamTaf 8y ago

zaarn 8y ago

ITER will never produce electric energy but they plan to achieve Q=5, ie, output 5 times more energy than put in. The more important work on ITER is work around enabling actual power stations using Q=5 and developing the tech to maintain operating fusion reactors (remote robots, etc.)

therein 8y ago
At that point can't you just store the output current in supercapacitors for later use anyway? You can even feed it into the machine itself. Supercapacitors easily have better than 20% efficiency for each cycle.
- zaarn 8y ago
  No, ITER doesn't have any planned way to make electricity, the power it outputs will be largely thermal and radiative. Engineers will likely put up a cooling system to measure the thermal output, especially after putting up the various ways to turn the major neutron radiation into heat (which is a fun way to produce energy with rare materials as a byproduct). DEMO, to my knowledge, will then include an actual electric generator to be hooked up to the fusion core.