What's the liberal take on nuclear fusion reactors?

[mistertrickster]

France is setting up a huge international consortium to develop nuclear fusion. What do we think? Is fusion the way out of our oil quagmire?

It sounds pretty good to me so far . . . as I understand it, nuclear waste from fission reactors can eventually be "burned" and disposed by the non-polluting fusion reactors.

*****

http://www.nuc.berkeley.edu/thyd/icf/IFE.html

Energy from Fusion
For fusion reactions to occur at sufficiently high rates to produce useful energy, light elements must be confined at sufficiently high density and temperature for a sufficiently long time. In the sun, gravitational forces provide this confinement, while on earth either magnetic or inertial forces must be used. Researchers in the U.S. and abroad now actively study both magnetic confinement fusion and inertial confinement fusion. Because discussion of the magnetic approach can be found elsewhere, these notes focus on the inertial route to fusion energy.

For fusion power plants, the easiest fusion reaction to generate is that of deuterium, the heavy isotope of hydrogen which is readily separated from water, reacting with tritium, a yet heavier hydrogen isotope produced from the inexpensive element lithium carried in the coolant that removes fusion energy from the target chamber. (Click on green-colored text to go to a glossary with definitions of words). The first chapter of these notes, "D-T Fusion: What is it?", provides a simple introduction to this D-T reaction and the conditions required to initiate it.

[amazona]

1. when I was a kid we were 20 years away from practical fusion energy

Now we're 50 years away.

It might not be the liberal take but the cynical take based on years of hype and promises that never come to fruition is that there are major barriers to making the technology practical and economic.

In other words, it seems to be pie-in-the-sky just like those jetpacks and cancer cures we were promised in the old Weekly Reader.

I'll believe it when I see it.

[mistertrickster]

2. You got a point there . . . but we had a "Manhattan project" to develop

fission. Maybe that's what we need for fusion.

[lapfog_1]

4. It may be something intractable

I don't have a "liberal" position on this... but I'm thinking that
the research dollars (and time) spent on fusion might have been
better spent on hydrogen economy transportation. It's not like we
haven't been spending Billions on this every year for 30 years.
$200 Billion spent on improving photovoltaics for a distributed
grid (improving the efficiency and lowering the costs), or $200
Billion spent on a hydrogen distribution system and solid oxide
fuel cannisters... Not to mention the TIME... 20 or 30 years of
more research!

On the other hand, if there was a fusion breakthough...

it's tough, but maybe about 15 years ago I would have cut the
programs and spent the money on other energy programs.

[Massacure]

9. How you going to make hydrogen?

With coal and natural gas???

[lapfog_1]

11. No... that's why it's called R & D.

Course, the most abundant source of Hydrogen on the planet is water,
that's where I would start. Hydrogen isn't so much a fuel (though
that statement isn't true if one goes off planet) as a energy
transport mechanism. For example, one could make a case that
IF there was a environmentally friendly way to burn coal or
gas (or even oil) that did not contribute to global warming (did not
emit CO2 or somehow sequestered CO2) and if one had a convenient
way to transport hydrogen, it would be MUCH better to burn hydrogen
in our autos rather than gasoline.

This takes research, and research needs both time and money.

Fusion research has had both, and has yet to produce something
which can be moved from Research to Development. And while we
haven't always given the fusion scientists every thing they've
wanted... we have committed enormous resources to the project
for a long period of time (the laser based NIF at LLL is the
latest in a long line of expensive test facilities built for
this purpose)... perhaps the time has come to look at using
new technologies to liberate hydrogen from other sources.

[Ediacara]

3. I love the idea

And I think that it's much much closer than 50 years off. The trouble is, there isn't enough being done to develop the reactors, since in the short term, coal is cheaper. In my opinion, the major obstacle now is one of engineering: how do you build a building that can 1) contain a reaction large enough to continue without stops and starts and 2) how do you build a building able to withstand a reaction that is (supposedly) holding at 100 million degrees C?

Both Kerry and Gore could have won by insisting on an Apollo program for fusion because fusion would have effectively reduced home heating costs to almost nothing (in the long term of course).

[midnight armadillo]

5. Those have been solved

In my opinion, the major obstacle now is one of
engineering: how do you build a building that can 1) contain a reaction
large enough to continue without stops and starts and 2) how do you build
a building able to withstand a reaction that is (supposedly) holding at
100 million degrees C?


They can already contain the 100 million degree plasma. The real challenge is having the reactor generate enough tritium to keep running. The plan is to do this by reacting the spare neutron (from fusing a deuterium and a tritium atom into helium and a neutron) with lithium lining the walls of the containment vessel. Without this, they'd need a fission reactor to supply the tritium...

The goal for ITER is to run for 500 seconds continously, producing a surplus 500 MW of power. They hope to accomplish this in 2015 or so. While it's a joke that we're always 30 years away from fusion, there have been huge advancements over the last few decades.

See also the discussion on this topic in the Environment & Energy forum.

I don't think there's a 'liberal' position on this topic - fusion has potential for future energy production, but in the meantime fission could be used without too much drama, especially with the new designs forthcoming.

[Kraklen]

6. I'm all for it.

Yes, it's always been "twenty" years away. But maybe if politicians didn't keep axing the research budgets maybe it wouldn't be. Take this ITER that they're hoping to build in France, that was supposed to be built in the U.S. ten years ago.

[alfredo]

7. I hope they can make it work. My problem is not the technology

but the ethical and intellectual deficiencies of those who control the technology.

[Deja Q]

12. Bingo. And beware of those who say "don't regulate". Their motives are

quite clear: Draconan and devolved.

[alfredo]

14. Some organized crime neighbors resented government

interference. They were big time Republicans. So was my check kiting boss. He kept a picture of Him and Reagan on the wall behind him so you can see it when you were in the office with him. He railed against OSHA and hid whenever he saw a police car coming down the street.

[GreenPartyVoter]

8. If it is clean, safe and viable, why not go for it?

[MadHound]

10. Nope, sorry, fusion isn't the panacea that is being claimed.

We still face the same two major problems with fusion that we do with fission reactors, waste, and human error.

Human error is what caused TMI to fail, along with Chernobyl. And that is going to be the same weakness a fusion reactor faces, with much the same consequences. One major mistake, and you've got radiation leaks, and possibly a reactor melt down.

And the waste from a fusion reactor is as bad or worse than that from a fission reactor. In other words, we're stuck with it for thousands and in some cases millions of years. We're having difficulty dealing with what radioactive waste we have, we don't need to add more to it.

Instead, we would be better off investing our money in alternative energies, wind, solar, biomass, biodiesel, etc. We can easily power ourselves with renewables, without any dropoff in our standard of living. There are few waste or pollution problems, and we won't run out of these energy sources.

Sorry, but nuclear in either fission or fusion form is not the way to go. You're just asking for trouble if you do.

[muriel_volestrangler]

13. A fusion reactor melt down?

My understanding was that the problem in fusion is keeping the reaction going, rather than stopping it. That means a meltdown shouldn't happen. And in what sense is the waste from a fusion reactor worse than from a fission one?

Will Iter produce radioactive waste?

Yes. The neutrons produced in fusion reactions will "activate" the materials used in the walls of Iter's plasma chamber. But one of the project's tasks will be to find the materials that best withstand this bombardment.

This could result in waste materials that are safe to handle in a relatively modest timescale (50-100 years), compared with the much longer lived radioactive waste (many thousands of years) produced as a direct result of splitting atoms in fission reactions.

It has been calculated that after 100 years of post-operation radioactive decay, Iter will be left with about 6,000 tonnes of waste. When packaged, this would be equivalent to a cube with about 10m edges.

http://news.bbc.co.uk/1/hi/sci/tech/4627237.stm

[MadHound]

15. Well I don't know where the BBC got those figures,

But they certainly don't match what the actual scientific studies are saying<http://www.acamedia.info/sciences/J_G/fusion.html> There are several elements that will become activated during the fusion process, and once activated their half lives range from thousands to millions of years.

As far as a meltdown goes, well of course it could happen. A nuclear meltdown is simply when the core coolant is lost for whatever reason(as we've seen, most often caused by human error), and the reactor overheats. Since a fusion reactor runs at temperatures of millions of degrees, even the most modest drop in coolant levels could cause catastrophe. Here are some papers explaining what could happen.
<http://www.inel.gov/relap5/rius/jackson/merrill.pdf#search='accidents%20fusion%20reactor'>
<http://www.osti.gov/bridge/servlets/purl/10110097-CAuZkK/webviewable/10110097.pdf>
<http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=6377679#>

Granted, the chances of this might be less than the chances of a meltdown in a fission reactor, but we really don't know this for a fact, since we've never built and operated a fusion reactor. This is unknown territory we're entering, and quite frankly the hype surrounding this technology resembles the PR that floated around at the start of the fission era. And like a fission reactor, even if there is a major accident at only one site, due to the nature of fusion energy, the accident will effect a great many people, lay waste to a large swath of land, and will continue to adversly effect generations to come.

Rather than going with such an unknown, and potentially disastorous technology, let us go with the known technology, wind, solar, biodiesel, and other alternative, known, safe and renewable energy sources. There is plenty of energy potential in these renewables to power the US for generations to come, and they are both safe and clean.

[muriel_volestrangler]

16. Perhaps the figures come from this European organisation

The European Fusion Information Network Web Site:

# a runaway fusion reaction is intrinsically impossible. Furthermore once its supply of fresh fuel is cut-off, the reactor can continue operating for only a few tens of seconds ;
# there are few radioactive waste problems : fusion generates no radioactive ash, and the unburnt gases are treated on site. Structural components of the reactor which have become radioactive through exposure to the neutrons will have to placed in storage - but, provided they are made of carefully-selected materials, the storage time could be less than one hundred years.

http://www.fusion-eur.org/fusion_cd/popu.htm

Of your links, the first comes from 1983; I have no knowledge, but perhaps the design has changed since then (I know this is only Wikipedia, and therefore may be inaccurate, but this Wikipedia article talks about the naturally occuring lithium isotope compensating for lost neutrons, so perhaps a neutron multiplier is not considered necessary now). The BBC link said part of this project is to determine suitable materials for the structure of the reactor that won't produce long-lived radio-isotopes.

The next 2 links talk about safety matters, but I can't see anything about meltdown; and the last is about a fission-fusion hybrid reactor, which is a different thing from a fusion reactor (they put fissionable material in the blanket on purpose in that one).

This PDF (from the European site) says:

• Inherent and passive safety
- Can Chernobyl-type accidents occur?
First, the amount of fuel available at each instant is sufficient for only a few tens of seconds, in sharp contrast with a fission reactor where fuel for several years of operation is stored in the reactor core. Second, fusion reactions take place at extremely high temperatures and the fusion process is not based on a neutron multiplication reaction. With any malfunction or incorrect handling the reactions will stop. An uncontrolled burn (nuclear runaway) of the fusion fuel is therefore excluded on physical grounds. Even in case of a total loss of active cooling, the low residual heating excludes melting of the reactor structure <18>.
• Radioactivity
The basic fuels (D and Li) as well as the direct end product (He) of the fusion reaction are not radioactive. However, a fusion reactor will require radiation shielding since it has a radioactive inventory consisting of (i) tritium and waste contaminated by tritium and (ii) reactor materials activated by the neutrons of the fusion reaction. Studies <18-20> indicate, however, that an adequate choice of the latter can minimise the induced radioactivity such that recycling should become possible after some decades to a century. Thus, radioactivity does not have to be inherent to nuclear fusion, in contrast to nuclear fission where the fission reaction itself leads to dangerous long-lived radioactive products.
The tritium cycle is internally closed, and the total tritium inventory in the fusion power plant will be on the order of a few kg, of which only about 200 grams could be released in an accident. Special permeation barriers will have to be used to inhibit discharge into the environment of tritium diffusing through materials at high temperature <18>. As tritium is chemically equivalent to hydrogen, it can replace normal hydrogen in water and all kinds of hydrocarbons. It could thus contaminate the food chain when released in the atmosphere. The absorption of tritium contaminated food and water by living organisms is a potential hazard. However, possible damage is reduced owing to the short biological half-life of tritium in the body of about 10 days.

[MadHound]

18. Interesting, but a puff propaganda piece nonetheless

Your source mentions little about the temperatures that the core will release, nor does it really deal with the activation of core components. And considering that there proposal is to manufacture tritium, well gee, they're going to need a fission reactor or cycletron to accomplish that.

This is really pie in the sky stuff, and having talked to nuclear engineers about this, it is fifty years at least before there is a chance at a safe, working reactor. And yet, it will still produce radioactive wastes. I realize that my first source was over twenty years old, however I put it out there for the equations concerning the half lives of isotopes that are going to be produced during the operation of a fusion reactor. I simply don't see how this EU piece is going to produce isotopes with half lives as small as they claim. They're still going to have to build the reactor out of steel and lead components, among others, and the half lives of isotopes produced from those two materials are in the thousands of years.

Again, why should we put a lot of faith in such an unproven technology? We already have more than enough fuel that can be derived from known, proven alternative, renewable fuels that don't produce such toxic waste, or are such a potential hazard to operate. It simply doesn't make sense.

[muriel_volestrangler]

20. No, the tritium is produced from the lithium

which is arranged around the reactor as a 'blanket' to capture the neutrons that the fusion reaction produces. Your link said that a 'neutron multiplier' would be needed, and some of the half lifes they quote are for materials that might be produced from that multiplier. The PDF I linked to from the European site does mention beryllium, though I can't find any recent figures on how much beryllium 10 might be produced.

The PDF did say the total heat would not be enough to melt the reactor. I'm not sure what you mean about the 'activation of core components'. I think the half lifes quoted in the link you gave are for trace elements in structural materials (which may be avoided with different alloys), or the multipliers (beryllium seems to be the one chosen for ITER; how much radioactive beryllium will be produced, I'm not sure).

Yes, it's unproven; that's why this is a prototype. There are questions whether it will be possible to build enough capacity from completely renewable sources (there is the storage question for both wind and photovoltaic), and research into a continuous process does seem worthwhile to me.

[MadHound]

22. Sorry, sometimes I talk shorthand

Like I'm at work, talking with a fellow colleague at the reactor, my bad. Activation of an element means that a normally inert ingredient becomes radioactive after being exposed to a large dose of radiation. For instance steel can become activated after only a couple of weeks in the core, depending on what its exposure is. Anything that goes into the core sooner or later becomes radioactive, it is the nature of radiation. It is also at the heart of what I do, which is working with radiopharmaceuticals.

And quite frankly, I don't know where the PDF piece is getting its info. Any nuclear reactor operates at many millions of degrees, that is why coolant is needed. Take away the coolant, and you've got major problems.

And there are no questions about the availability concerning renewables. A 1991 DOE report has stated that there is enough harvestable wind energy in three states, North Dakota, South Dakota and Texas, to supply our nations electrical needs through the year 2030. Combine this with a biodiesel hybrid, along with solar and the others, and you have a sane, sensible energy policy. Storage for both wind and solar is simply done by the grid, I'm producing in Boston, yet you aren't in LA. My excess energy goes cross country via the grid and powers you.

There is no need to go rushing headlong into this unproven technology, not when there is such a catastrophic downside to it.

[karlrschneider]

17. I'm a liberal who often disagrees with liberals

;-)

But as a scientist and engineer, I'm very much in favor of trying to make a working fusion machine. I doubt I will ever be convinced it can NOT be done. :D

[fla nocount]

19. If there were a way to strap a meter on a sunbeam. We would have

stopped having conversations like this decades ago. The Templars, the Robber/Railroad/Oil Barons, the landed Gentry, the MSM....whatever you want to call them, have a vested interest in creating an illusion of lack when it comes to the only universal commodity which is ENERGY. Be it spiritual (religions), physical (big pharma, water monopolies, GM foods,etc.) Perception and consciousness in all their facet's rely on ENERGY. Without it we're all dead in a dead world. Our masters know this and thus pukes come to power.

Energy is everywhere in everything where we are conscious. It's in the wind that blows our hair, the sun that warms our backs and the heat from our bodies. It is the one thing that drives the universe and it has no limits. It is everywhere.

It's not lack of imagination, Tesla wasn't an anomaly. It's suppression of imagination, of knowledge that limits us. This suppression is focused, it's intentional and it's malevolent. It's also ancient.

Just my two cents.

[freethought]

21. I say "Go For it!"

First-if you want to develop fusion energy, you're not going to get there by standing still. Sure it may take years to develop a commerically viable tommakak (the name for a fusion reactor). One can not expect to get there by doing nothing.

Second-some posters have called this 'unproven' technollogy. Well, when it starts out, just about any technollogy is unproven. The point is to prove it.

As far as safety is concerned there is the 'human factor'. Consider fission power now. The U.S. record of safety is, overall, good. We have one accident, fortunately it was contained. If you want to site Chernobyl, just remember the plant management was doing something they should not have been doing and they knew it. We live with human factor of mistakes every day. Developing fusion is worth the risk.