
Nations collaborating to build world's largest tokamak - bryanrasmussen
http://www.iter.org/proj/inafewlines#4
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taf2
" plant will use this heat to produce steam and then electricity by way of
turbines and generators"

Has anyone thought of a better way to "harness" power to produce electricity
than heat? I'm guessing in the future there will be a more efficient way that
changes how we think about the production of electricity.

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olegkikin
The efficiency of modern steam turbines is not too bad. And considering that a
lot of energy is used for water heating anyway, the overall efficiency (term:
co-generation) is even higher.

~~~
jessriedel
Importantly, according to this

[https://physics.stackexchange.com/a/191465/7911](https://physics.stackexchange.com/a/191465/7911)

the efficiency of steam is not far from the thermodynamical maximum under the
assumption that the nuclear energy is initially converted into thermal heat in
solid objects. You can do better, but only by harnessing the fission products
(neutrons, protons, etc.) themselves before they thermalizes with surrounding
material. This is possible, but it's a completely new and separate challenge
in nuclear engineering, with a maximum improvement of about a factor of 2 in
energy efficiency.

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IgorPartola
My understanding of this was that basically we have achieved the scientific
break even point already. That is we can have short lived fusion in a tokamak
where we produce more energy than is consumed by the reaction. The trick is
getting to practical break even: you also need to power the magnetic field.

It seems that we are getting closer with every attempt to getting to that
break even, but it is very slow progress. I also remember reading something
about an attempt at building a tokamak that didn't run continuously, but in
short bursts. The idea was that it was more feasible to actually get closer to
the break even that way.

Anyone have a quote in what our current best efficiency is?

~~~
dave_sullivan
I saw this a while back and thought it was a good summary:
[https://youtube.com/watch?v=L0KuAx1COEk](https://youtube.com/watch?v=L0KuAx1COEk)

I forget the current best efficiency, but it's getting close.

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jcoffland
> ITER will not capture the energy it produces as electricity, but—as first of
> all fusion experiments in history to produce net energy gain—it will prepare
> the way for the machine that can.

So this is a very large and expensive project that will never produce any
actual electricity. Seems at high risk for budget cuts. No one can predict the
political environment over the next decade. If it's anything like the last
ten, this project is at risk even of they can stay on schedule and within
budget.

~~~
losteric
Our irrational prioritization of public spending is seriously disheartening.

On one hand we have ITER, an international ~$20B R&D investment that pays
dividends even if it fails - and America's 10% commitment is rightly seen as
politically uncertain.

On the other hand, American's almost take for granted that we must spend $300B
_every year_ on war in the Middle East - for inarticulable and unquestionable
reasons.

Imagine where we would stand if we turned just 10% of that fraction of our
total military budget towards advanced R&D... commercialized fusion would
literally revolutionize the world, and the technology would be an irresistibly
compelling diplomatic carrot (esp. in the Middle East, in the form of cheap
desalination)

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Mizza
But are they going to be leapfrogged by the stellarator?

~~~
jcoffland
Here is a good explanation of the differences between these two types of
reactor:

[https://m.youtube.com/watch?v=vqmoFzbZYEM](https://m.youtube.com/watch?v=vqmoFzbZYEM)

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m-j-fox
2035 is a long time from now. Hope someone hatches a practical energy plan in
the meantime.

