International Thermonuclear Experimental Reactor (ITER)

Discussion in 'General Science & Technology' started by Success_Machine, Apr 8, 2002.

Thread Status:
Not open for further replies.
  1. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    ITER - "The Way" translated from latin. It is expected to be the first fusion reactor to produce power far beyond break even, and lead immediately to construction of dozens of commercial fusion powerplants.

    <A href=http://www.wired.com/news/technology/0,1282,48000,00.html>Wired Article</a>

    <a href=http://www.iter.org/>ITER homepage</a>

    With 15 years of oil left before exponentially increasing demand in Asia-Pacific countries causes worldwide shortages, we need a clean power source to produce hydrogen for transportation. Ordinary nukes produce long-lived radioactive waste. Coal liquefaction has immediate pollution problems. Maybe fusion power should be pursued forthwith. If it is not possible then we should get it out of the way and concentrate on real solutions.
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. goofyfish Analog By Birth, Digital By Design Valued Senior Member

    Messages:
    5,331
    Do you know where this figure comes from?

    Peace.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    International Thermonuclear Experimental Reactor

    I did a numerical analysis based on BP worldwide oil statistics. The result is that there will be rather profound oil shortages by 2015, which is actually just thirteen years from now, not fifteen. This shortage will be caused by the exponential increase in Asia-Pacific oil consumption, and also by the simultaneous exhaustion of reserves in North America and Europe, and their need to import. By 2015 nearly all the oil supply in the world will come from one place, Saudi Arabia, and they won't be able to meet such extraordinary demand. In fact just 10-15 years after that there won't be any oil left at all. The exact date when this will happen is open to debate of course but the timeframe is fairly certain from my perspective, within a few years of actual.

    So we will need something to help produce hydrogen for transportation. Will fusion be available? The reports from ITER-Canada say that it will not be available in time, but they also say that the slow schedule is partly political. There isn't enough support for the project and that is slowing it down.

    I would like to know if fusion can really happen. There is alot of skepticism surrounding it.
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Deus Seeker of Truth Registered Senior Member

    Messages:
    65
    One thing I think they might run into if they try to use fusion engines for transportation is that even if you can produce more energy than you need to create the reaction, there is still a large amount of energy required to start the fusion. That means either we need really good battery technology or something else that can start the reaction.

    Then there's the obvious question of what happens in a crash? You don't have to worry about any radioactive waste with fusion, but the vehicles involved will most likely be destroyed or severly damaged if the magnetic field containing the plasma is destroyed.

    As far as for regular household electricity, I think regular fission plants work fine for the time being. Fusion would be greate down the road, but right now fission plants work pretty well, especially if you recycle the waste until you can't get any more fuel out of it. Then, not only do you end up with much less waste, but the half life of the waste is much less. I wish more countries, especially the US, would do this.
     
  8. goofyfish Analog By Birth, Digital By Design Valued Senior Member

    Messages:
    5,331
    What, and give up our pollutant-belching smoke stacks?

    Please Register or Log in to view the hidden image!



    Peace.
     
  9. Deus Seeker of Truth Registered Senior Member

    Messages:
    65
    There is an old brick smokestack in the city I live in. It's the only remaining part of a factory that used to be there. I guess the city thought it was cool since it's still there and there is a park behind it where the factory was long ago. That would be a nice end to all smokestacks, eh?
     
  10. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    Hydrogen Fuel for Transportation

    I did not mean to suggest that nuclear engines be used for transportation. Rather, I suggested that nuclear fusion reactors could be used to produce hydrogen, which in turn would be used as a fuel for cars, trucks, buses & airplanes.

    But like I said, it doesn't look like fusion will be developed sufficiently to be useful by the year 2015. Therefore we'll probably have to use ordinary nuclear fission powerplants, or coal liquefaction to produce fuels to offset oil shortages.

    I don't know how significant politics is to the development of fusion, but if it could speed things up it would be nice. I for one would like to know if fusion is possible.
     
  11. Deus Seeker of Truth Registered Senior Member

    Messages:
    65
    There are other ways to get hydrogen. Did you see that BMW has a hydrogen powered car that they are showing off? I forget how much the thing would cost to actually buy. I just hope we start moving to cleaner transportation soon.
     
  12. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    Check this out

    General Motors concept car "Autonomy", powered by hydrogen fuel cells:

    http://www.edmunds.com/news/conceptcarspotlight/articles/48581/article.html


    Sadly, I don't think it will be possible to produce hydrogen in sufficient quantities to support personal transportation, perhaps only mass transit, and cargo transport (locomotives, container ships, tractor-trailers, emergency vehicles, etc).

    While hydrogen cars like the ones produced by BMW and GM may look great, only a few people might buy them. Everyone else will end up buying smaller and smaller cars, until they just give up because there is no more fuel left.

    Nuclear fusion may be the only way to produce sufficient hydrogen without generating huge quantities of radioactive waste or air pollution. But we don't know if it will work?
    This is a question that needs to be answered in the next 10 years in my opinion. Any later than that and it will be too late.
     
  13. goofyfish Analog By Birth, Digital By Design Valued Senior Member

    Messages:
    5,331
    Too late for...?

    Mankind starves for oil and war is the result?
    Research is forced into exploring alternative power?
    Governments start over with Feudal-agricultural societies?
    Global starvation, populations fall dramatically?

    What do you mean?

    Peace.
     
    Last edited: Apr 9, 2002
  14. Success_Machine Impossible? I can do that Registered Senior Member

    Messages:
    365
    Expected 60 years before fusion power

    By too late I mean after 2015 we will have to increasingly rely on polluting nuclear or coal for energy & fuel. Fusion wont' be available for several decades, so neither will a clean source of automotive hydrogen.

    Here is a summary taken from the ITER homepage:


    Fusion power was produced in [previous] experiments - the record now is about 10 MW - but only for a second or two.

    During these experiments the whole experimental plant was consuming more than 100 MW, so no prizes for these experiments as a power source! The problem is that these experiments are too small to generate sufficient power to make a power source, whereas ITER would be in the size range where a reactor could operate. Based on extrapolation from existing experiments, ITER should generate 500 MW of fusion power for the range between several hundred seconds up to continuous operation. This power shows up as heat which is cooled away. In principle, you could connect up a steam turbine and generate electricity with this heat (ITER will not do this for efficiency, cost and reliability reasons), which might give about 150 MW of electrical power. The power taken to run ITER is about 110 MW electrical, so ITER could sell about 40 MW electrical back to the grid. Of course a commercial scale reactor would need to be just a bit bigger (or work a bit better - it is not yet clear which - hence the need to construct ITER), so that a fusion reactor would have typically 4000 MW of fusion power (1300 MW electrical power) and hence sell ~1000 MW to the grid.

    The problem with hot fusion is rather getting it to work at all, since it requires special conditions which are easy to go outside, causing the reaction to die out. Then of course although the fuels are cheap, the capital investment up front is rather high, requiring a lot of confidence from the investors that it is going to work (hence the worldwide experimental development programs which spreads the risk of failure so everyone's cost is minimised, and so that when we eventually get to building power reactors we can be confident they will work). Thirdly for fusion to not create radioactive waste that hangs around for a long time (>100 years) existing structural steels and other materials will have to be developed a bit to rid them of problem isotopes (but here already ITER is pretty good with most of its materials available for recycling after 100 years storage) and to test them so the nuclear regulators will sanction their use.

    Actually where fusion goes and whether it gets developed at all depends on the taxpayer and his elected representatives. They have taken the initiative to put together programmes of fusion research around the world and most of these programmes lead on to our machine, ITER, as their next logical step. ITER is however just an experiment so they have taken this decision because presumably they foresee an energy shortage coming up in the medium term and want to collaborate on developing one way to overcome it. How well fusion stands up against the alternatives is something we in the business cannot decide. We can only advise.

    So the simple answer is that we are almost ready to go ahead and build ITER. It just needs the commitment of the governments and therefore the taxpayers concerned. We can only advise them that we think we are ready, can do it and that it is essential to do it for longer term energy (and hence economic) stability. It's then up to them. The building of ITER would take 10 years, and 20 years are foreseen for operation, so we could probably start designing DEMO by 2020, and if needed operating it by 2035. This puts the first commercial fusion power station (the step after DEMO) on line at the earliest in about 2050.

    ITER is not an electric power producing reactor. In some respects, like plasma size, ITER is like a prototype power reactor, but in others it is far away. That's why the first commercial implementation of fusion has to remain in the middle of the next century. There is still lots more engineering to do to make the device reliable and economically competetive.

    ITER will therefore not produce any electrical power, except in a token experiment using a test blanket module to show it is possible. To use conventional steels in our experimental plant (necessary to get nuclear licensing) we have to operate at relatively low temperatures. These are not the best for steam raising so we have saved ourselves the cost of a turbogenerator, thermal store, etc. ITER will also be a pretty unreliable energy source at the beginning, so this also makes sense from that viewpoint. The heat will be rejected to the environment, probably via cooling towers. In the follow up device - DEMO - conventional steam raising and power generation will be used.

    Up to now fusion experiments have addressed only the scientific feasibility of fusion, with little attention to how it can be turned into a practical electrical power source. ITER is the first really "nuclear" fusion experiment, which from the outset has to be designed to satisfy anything mother nature and the safety regulators can dream up, as well as to be repairable when it fails. The only convincing experiment is one conducted in the real environment, and ITER will be the first time prototypical fusion power reactor technologies will be put together with plasma physics to try to make a viable power source. No doubt we will get some of the technology wrong, and make some items at unnecesary cost, but we will only find that out by trying this step. Further speculation from today's knowledge base will tell us nothing.

    ITER will really be the first fusion device that produces more energy than it consumes, but for a limited time. Experiments so far (like JET, TFTR or JT-60) have attempted to reach "breakeven" - a point where the fusion power produced by reactions in the plasma is equal to the power you are putting into the plasma from outside to keep it hot. However although going close, they have not achieved this. ITER will produce many times more power from fusion than it consumes as power input to the plasma, just because of the scaling to larger size. Bigger plasmas are easier to keep hot than small ones. However, be careful in your understanding, I am talking about thermal power (i.e energy transfer rate - J/s - at a given time) and not electrical energy (i.e J). ITER will not be used to generate electrical energy (i.e electricity), except on a token small scale to indicate that we can do it. That is because we would have to design a higher temperature blanket around the plasma to do this efficiently, which it is not worth designing (we will test our ideas on ITER but in special test cells which also include prototypical tritium breeding) and installing turbogenerators (which would cost more money). We would also have to operate with short times between pulses or in steady state, and we don't know how to do that yet and want to keep costs to a minimum for this experiment. The thermal energy we create when the plasma is operating will be dissipated into the environment via cooling towers. However we will need electrical energy to drive our systems and heat the plasma using microwaves and neutral particle beams. So in this sense only the machine afterwards (DEMO) will be a net producer of electricity (if that is what you mean by energy). However if you add up all the electrical inputs to the plant in ITER and convert them to thermal energy, and compare that with the thermal energy we can produce operating our pulsed device as often as we can, even ITER will produce more thermal energy than it consumes.

    http://www.iter.org
     
Thread Status:
Not open for further replies.

Share This Page