[ExI] Could Thorium solve our energy problem?

[Adrian Tymes]

--- On Fri, 7/9/10, Henrique Moraes Machado (CI) <cetico.iconoclasta at gmail.com> wrote:
> <Brent Neal, Ph.D.>
> > The relevant data are:
> > 4.3 Mton world thorium reserves (source: OECD)
> > Energy density: 80TJ / ton thorium (estimate based on
> conversion to U233 via slow neutrons)
> > World energy consumption (2006): 498 EJ (source: EIA,
> IAEA, OECD)
> > World energy annual growth rate (computed from
> 1980-2006): 1.8%
> > The calculation of when the cumulative energy usage
> exceeds the energy available in the world's reserves of
> thorium is left as an exercise to the reader. Please note
> that you have to include the efficiency of a Carnot engine
> in the calculation for full marks. :)
> </Brent Neal, Ph.D.>
> 
> A thousand, ten thousand, a million. Even a couple hundred
> years would buy more than enough time to develop a usable
> fusion solution.

Not even one year - at least for full displacement.

4.3 Mtons * 80 TJ/ton = 344 EJ < 498 EJ

And that's without the Carnot engine and other unavoidable
inefficiencies (for instance, you can't simply teleport the
thorium to the reactors, so there's transportation and
extraction costs as well), which could easily reduce the
energy actually obtained to less than 1% of this amount.

Based on that data, the answer to the thread's titular
question appears to be "no".  It could perhaps solve a very
small part of the problem, but apparently not enough to be
worth much investigation.  (Now, if someone could find a way
to get far more than 80 terajoules from a ton of thorium,
that might be of use.)