ITER tokamak cannot be self-sufficient in tritium breeding

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Drakkith said:
Umm, I don't think that looking 5 years in the past is sufficient to say that future energy demand won't/isn't increasing.
"Won't" and "Isn't" are to very different things. I did not say "Won't". The data says, not me, that for the last 5 years US electric demand "Isn't" increasing (linear fit).
A quick look on that table shows that up until 2008 there was a continual increase. ...
The 5 year window is sufficient to say this: the 5 year trend (ie lately) is flat or down with a linear fit to those numbers, no more no less.
US billion kwh vs year:
1zmph0x.png
 
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• Till 2008 increasing.
• After August 2008 (crisis beginning) some fall which if we call as” trend" - very short term
• After the end of crisis - do not know but think that growth again
 
Let me put it this way mheslep. Your post was pointless and serves no purpose in regards to this thread. Not only did it not refute what you quoted, it ignores all long term trends, other variables, and only takes one single country into account. So what if the US energy usage has flattened out in the last few years? That has no bearing on this discussion.
 
Drakkith said:
Let me put it this way mheslep. Your post was pointless and serves no purpose in regards to this thread. Not only did it not refute what you quoted, it ignores all long term trends, other variables, and only takes one single country into account. So what if the US energy usage has flattened out in the last few years? That has no bearing on this discussion.
Ah, good, then the US can drop all support for ITER.
 
Poitevin's description of tritium-breeding blankets has moved, available here:
http://www.iter-industry.ch/wp-content/uploads/2010/01/Pr__sentation_Poitevin.pdf
 
Poitevin's Pdf tells that beryllium could be an other neutron multiplier, as an alternative to lead, but beryllium is scarce.

Believing the miners at USGS rather than the chemist cited by Wiki, we have 80,000 t of beryllium ressources - exploitable ore, not reserves which limit to present economic conditions.
http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/mcs-2012-beryl.pdf page 29

According to the IEA, the worldwide energy consumption was in 2008:
http://www.iea.org/textbase/nppdf/free/2011/key_world_energy_stats.pdf (pages 24 and 6)
- 15 PWh = 54 EJ as electricity made from hydrocarbons (including coal) or from uranium;
- 10 Gtep as hydrocarbons (including coal) or uranium, or 440 EJ replaceable by 300 EJe of electricity.

1 mole or 9g of beryllium produces about 1,4 mole of tritium of which each atom produces 25MeV heat converted to 35% in electricity, or 130 TJe/kg of Be.

If other uses continue to need 270 t/year of beryllium, ressources cover :
- 120 years of electricity, needing 270 + 410 t/year. That's less than coal;
- 31 years of hydrocarbon replacement, needing 270 + 2300 t/year - and we want to replace hydrocarbons.

With beryllium as a neutron multiplier, ITER wouldn't hold it promises. Even if it only produced the electricity presently consumed, its R&D would have been longer than its operational life.

Except if someone sees a better neutron multiplier (no Th nor U nor Pu, thanks), we have only Pb and its radioactive waste.

Marc Schaefer, aka Enthalpy