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PostPosted: Nov 29, 2009 10:09 am 
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The AHWR-300-LEU is designed primarily for export

This is news to me !

From what I heard, its the old 220MW CANDU design that they plan to market abroad (these are clones of the Douglas Point reactor in Ontario).

We have enough confusion about nukes in the media, even without this....


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PostPosted: Nov 29, 2009 10:27 am 
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jaro wrote:
From what I heard, its the old 220MW CANDU design that they plan to market abroad (these are clones of the Douglas Point reactor in Ontario)


In all fairness, they have extended the design out a bit, and modernized it. The real shame is that AECL didn't have the foresight to do it first.


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PostPosted: Nov 29, 2009 12:11 pm 
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DV82XL wrote:
In all fairness, they have extended the design out a bit, and modernized it. The real shame is that AECL didn't have the foresight to do it first.

Good point.

But consider also that here (and in the West in general) the regulator does not allow deployment of modular power plants using a series of small reactors: Each reactor, regardless of size, has to have its own complete set of independent structures, control room, safety equipment, operating staff, etc.
Thus there is a strong incentive to design & build large reactors, to take advantage of the economy of scale, rather than economy of mass production.
Never mind that the US Navy (and others) have demonstrated for many decades that operating ships with several reactors on board can be done quite safely (I believe some aircraft carriers have as many as 4).

India will likely run into this problem sooner or later.

They could do everyone a BIG favour by pioneering the licensing of those 220MW export reactors as modular units, part of a SINGLE nuke plant, to be run from a central control room, etc.

The same regs may then be applied to other modular reactor designs, including PBMR, AHTR, MSR, etc.

Until this happens, there will be little private interest in investing in small reactor development.

In other words, the regulator is stifling development.

India could lead the way in breaking through this.

So far, only the Russians appear to have found a way around the road block, with their KLT-40S barge-mounted twin reactors.
Hopefully their barge design is readily scalable -- to accomodate sets of 4, 6, 8 etc. reactors....


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PostPosted: Nov 29, 2009 3:44 pm 
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Well if I am reading them right, they are more interested in selling single plants to places that would have no need, or cannot afford larger ones. When we are talking about the small reactor market in the West we are generally thinking along the lines of small highly sophisticated devices that ideally could run with minimum oversight. The Indians are offering an entry-level plant that will serve as a technology transfer platform, a starter reactor if you will, that will be used to train a generation of technicians.

This has also been the role of CANDU reactors in many places, India itself being the prime example, and I feel we could have continued to sell plants in the 200-200MWe range to those same nations that are talking to India now.

Also look at the West Indies - this is an ideal size for many of the markets down there especially combined with desal. AECL could have even operated them on a lease bases as merchant plants. There are other examples too of markets that could have been exploited with that size of reactor.

As I see it AECL got into a competition with the LWR crowd, and found themselves out of their league trying to play catch up in unit size. Now we are left with a white elephant of a design, that even we won't build, and our ex customer is going to eat our lunch.


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PostPosted: Nov 29, 2009 7:57 pm 
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Prices are lower in India and China. Chinese have too much to do at home now. Later they will corner the market in nuclear reactors as they have in many other items. India have not got an order yet. Still talks continue for import of reactors due to assured fuel clause even with France who have the highest costs. NPCIL may do the civil works themselves and reduce the costs somewhat. The main attraction is the 'spent' fuel which shall yield fuel for fast reactors and then the thorium fuel!
Similarly Chinese or Indian reactors built outside will have to face local costs in many items.


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PostPosted: Sep 07, 2010 2:12 am 
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Axil wrote:
J. Slough made a very recent presentation of his Field Reversed Configuration (FRC) at UCLA describing his recent fusion efforts and future plans as follows.

http://www.fusion.ucla.edu/FNST/Renew_P ... 20talk.pdf

He has achieved 10e15 neutrons per pulse. The next stage in his development plan is to ramp up the pulse rate to about 1000 pulses per second. That will get him to a fluence of 10e18 neutrons per second.


Axil, do you know of any peer reviewed journals where the claim of production of 10e15 neutrons per pulse by John Slough and staff was reported?

Could you point me at any source that would confirm the production of 10e15 neutrons per pulse from Slough's current FRC experiments?

Thanks for your kind consideration of my question.


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PostPosted: Sep 08, 2010 1:57 pm 
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The claim was made on slide 11 of the referenced presentation as follows: “Phase1: IPA-HF(2010) Nneut ~ 10^15/pulse”



The research of Dr. John T. Slough is funded through peer reviewed government sources including NASA, the department of energy, and the air force office of scientific research.

When the US government spends money sponsoring energy research through the legislative process, peer review is a prime concern.

the House Committee on Science and Technology’s Subcommittee on Energy and Environment routinely holds public hearings to examine the next generation of fusion energy research. Specifically, the Subcommittee looks at both domestic and international partnerships in fusion energy research and programs within the Department of Energy (DOE) Office of Science’s Fusion Energy Sciences (FES) program and DOE’s National Nuclear Security Administration (NNSA).


“Fusion energy has successfully powered the sun and the stars for billions of years, so it’s no surprise that man would try to recreate and harness this energy source here on earth. However, we all know that a working fusion reactor has been much more difficult to achieve than our atomic-age scientists initially expected,” stated Subcommittee Chairman Brian Baird (D-WA). “Over the years, there were also some overly optimistic or even fraudulent proclamations by self-identified fusion researchers who skipped the peer review process and went straight to the media, further complicating the popular and political assessment of the extent to which the federal government should continue to support this research.”

Today, the DOE is scrupulous in meeting their peer review responsibilities pursuant to the expectations and funding requirements of the US congress.

It is clear to me if any fraudulent and unsupportable claims are made by a fusion researcher in an attempt to deceive; he will risk losing his support and funding provided by the associated responsible executive branch department that administrates this funding for the US congress.

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PostPosted: Sep 08, 2010 9:12 pm 
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Axil wrote:
J. Slough made a very recent presentation of his Field Reversed Configuration (FRC) at UCLA describing his recent fusion efforts and future plans as follows.

http://www.fusion.ucla.edu/FNST/Renew_P ... 20talk.pdf

He has achieved 10e15 neutrons per pulse. The next stage in his development plan is to ramp up the pulse rate to about 1000 pulses per second. That will get him to a fluence of 10e18 neutrons per second.


What this paper means is unclear because they are only notes from a lecture. The graph that mentions 10e15 neutrons appears to me to be a calculation, not actual results. Where are his actual results published?

Remember, fusion is easy, but break even is horrendous.


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PostPosted: Sep 09, 2010 3:58 am 
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On one hand, the fast reactors are essencial for fissile material economy for uranium poor countries like India, (uranium exporters are in single figures) and on the other hand thorium based fuels and particularly U233 gives good neutron output in reactors. It could be that fast thorium reactors while not with best breeding ratio (There is no fast fission of thorium) will be the energy saviour for India and the world.
Molten salts and particularly FLiBe are moderating to some extent and are suitable for thermal spectrum. Sodium is too fire prone even if the Russians and Indians are building a reactor apiece with sodium coolant.
As far as thermal spectrum thorium fueled reactors are concerned, my mind, after going through all the discussions, goes to a uranyl salt solution in light or heavy water. That would be a fluid fuel with easy removal of volatile fission products like Xe and Kr. Sulfate or some other acid radicals, while keeping uranyl in solution, could precipitate most of Samarium reducing neutron loss. As far as thorium is concerned, it is more difficult to get into solution and should best be kept solid.
As far as liquid metal coolant for fast reactors is concerned, Al-Mg eutectic, while melting at a higher temperature than sodium (around 450C), reduces fire risk to a very large extent. It also has a high thermal conductivity and low neutron absorption. It could replace sodium or fused salts. Like them, it has a low vapour pressure and avoids very heavy castings. It boils high enough for a high temperature reactor.
I hope Indians are able to produce thorium fueled reactors for themselves and for good of the world sooner rather than later.


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PostPosted: Sep 13, 2010 1:49 pm 
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pstudier wrote:
Axil wrote:
J. Slough made a very recent presentation of his Field Reversed Configuration (FRC) at UCLA describing his recent fusion efforts and future plans as follows.

http://www.fusion.ucla.edu/FNST/Renew_P ... 20talk.pdf

He has achieved 10e15 neutrons per pulse. The next stage in his development plan is to ramp up the pulse rate to about 1000 pulses per second. That will get him to a fluence of 10e18 neutrons per second.


What this paper means is unclear because they are only notes from a lecture. The graph that mentions 10e15 neutrons appears to me to be a calculation, not actual results. Where are his actual results published?


Remember, fusion is easy, but break even is horrendous.



One of the indispensable tools in the development of a nuclear based product is a reliable and comprehensive mathematical/computational model of the processes involved in the product.

This method of system validation holds true for fusion development.

As an interested observer of fusion development, one of the big design testing validation criteria is the conformation of the fusion power or “neutron production scaling equations”. Each fusion system design has a unique scaling equation that projects how an increase in various dependent systems related quantities project to increases in power, heat, and/or neutron production.

The calculations and projections that appear in the referenced presentation are also found in various published papers.

http://burningplasma.org/web/ReNeW/whit ... source.pdf

Quote:
A plot of the neutron yield per pulse as a function of the two key variables can be found in Fig. 2. The IPA (2008) result was actually obtained at Ti ~ 1 keV and ZedP = 1 mWb in deuterium. The data point represents the yield expected if a DT fuel was used. Improvements planned for the current IPA device are to increase the energy of the FRC by an additional stage of acceleration and increase the compression field substantially. With these upgrades, the neutron yield will be increased by over two orders of magnitude. The target yield for the Component Test facility (CTF) would be obtained by employing a larger source, an additional stage of acceleration, and a somewhat higher magnetic field. This facility can be constructed in less than 2 years. With a parallel development aimed at validating the envisioned repetitive pulse power technology, a prototype CTF could be completed within three years. Given a 20 Hz rep rate, this device would produce an average neutron output of ~ 4x1017s-1, spread over an axial extent of ~ 1 meter depending on the FRC post merging length. This would represent a wall loading of 1.6 MW/m2 at the burn chamber wall. Higher loading can be obtained by increasing Ep, B, or ZedP.


For example, I don’t believe that a 15T superconducting magnet currently exists right now. But such a magnet is in development. When this increased magnetic field is applied to the Helion design, the scaling factor will produce the associated neutron flux.

The same is true for the reputation rate. This is another design requirement that will be demonstrated eventually. The same is true for D-T fusion.

Nobody works with tritium because of the problems of exposure, contamination, and containment. As an alternative, deuterium is used in experimentation.

When the Component Test Facility is funded and built then all the dependent fusion variables can be fully expanded and the associated neutron flux scaling equations can be fully validated.

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