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Fusion Reactor Sets New Endurance Record
!splut writes "Fusion fans out there will be interested to know that an experimental French fusion reactor has set a new duration record of 210 seconds. Most fusion reactor research works (or tries to) by containing and compressing a quantity of plasma via an electomagnetic field in a toroidial chamber. Fusion energy could potentially provide a a clean, efficient, and virtually inexhaustible source of energy, but fusion reactoins have proven difficult to contain and control, so this is a significant achievement."
Grumble, Grumble
What needs to be understood is that they've managed to use a fusion generator to generate electricity. However, they've never managed to create electricity in a useful fashion.
As it stands, they can create an efficient reactor that is not self-sustaining or a self-sustaining reactor that is not efficient. In other words, the former uses very little outside power, but isn't stable and ceases to function. The latter is more stable, but uses more fuel than conventional means.
Fusion power is not a pipe dream. Just as conventional power reactors have been improved over time to produce electricity more efficiently, so will fusion reactors eventually be improved to the point where they're useful. Will it be in the next decade? It may well be, but regardless of when it will happen, it will happen.
The same french tokamak (Tore Supra) had set the previous record of 120 seconds in 1996.
The figures on this page (in french) shows that the reactor produced 2MW during most of that 1996 experiment. That is 2MW of *excess* power for such a small experimental reactor!!!
Actually fusion really isn't the miracle power source they have made it out to be. Sure, it doesn't pollute, and the fuel cost is almost peanuts. But the reactors themselves will always cost huge amounts of money and still take quite a bit of manpower to run.
However, fusion will still eventually end up somewhat cheaper than other forms of power generation. It just isn't a miracle "too cheap to meter" type of thing.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
I think that you have fallen into a semantic trap.
"Sustaining" is too vague. The ultimate definition of a "viable", or "commercially usable" reactor is one that produces enough power so that by selling that power it can pay for itself, it's fuel, staff, etc. This is what an electrical power plant does. It costs $X to build, $Y/yr to maintain, and operate. If the power that it generates can be sold for > X + (Y * useful_lifespan), then the power plant is viable and probably will be built by somebody.
There are designs for fusion plants that are purposefully not "sustaining". Instead, they pulse. During the pulses, they make more than enough power to fire off the next pulse. What they don't do, yet, is make enough to fire off the next pulse, AND pay for themselves.
Good judgement comes from experience, and experience comes from bad judgement.
- W. Wriston, former Citibank CEO
Self-sustaining does not mean never-ending. What it means is that no more energy is required to continue the reaction, but if your fuel runs out, you're toast. Look at the sun (or any star for that matter). They're self sustaing, but they don't last forever. Eventually they run of fuel and collapse or explode.
The origional poster was correct, a huge amount of energy is used to initiate/control this reaction. Fusion reactions do release (not create) an amazing amount of energy, but so far we have had to use an even more amazing amount of energy to control it. We are getting closer and closer to breaking through the efficiency barrier, and I don't doubt that we will someday. It's just going to damn slow.
Well, we have been able to get a massive payback in terms of energy release. It's called a hydrogen bomb. A conventional fission bomb is detonated right up against a bunch of hydrogen isotopes, quickly achiving the tempuature and pressure necessary in order to fuse.
BOOM
Don't Bogart the fish sticks