Fission power inherently zero cost (was The single-shell city can be

> > There are no lower bounds for the cost of terrestrial nuclear
> > power. Add automation and scale, and the cost modulates toward
> > zero.
> How can you seriously argue that there exist no lower bounds for
> the cost of terrestrial nuclear power?

The fuel supply is vast -- 40 trillion tons of uranium alone.
The fuel is energy-dense -- $100/bbl oil = $1 million/kg uranium.
The fuel can be mined robotically.
The fuel can be processed and assembled robotically.
The reactor units can be built, fueled, and run robotically.
The spent reactors and spent fuel are dense and contained and
therefore easy and cheap to deal with. Simply mothball them
(today, this is called SafStor for the reactors, and
onsite-storage for the spent fuel). The radioactive-flux
continuously decays. Someday, a team of robots might come along
and recycle everything. If not, there would be no loss.
http://www.google.com/search?q=SafStor+nuclear

> The Council of Foreign Relations looked at the issue of uranium
> supplies:

There has recently been turbulence in the uranium market. The CFR
article explained why. The present spot-market price is $60/lb,
down from the CFR article's quoted price of $138/lb some nine
months ago.
http://www.uxc.com/review/uxc_Prices.aspx

The long-term view is an approach toward zero-cost for uranium,
as long as demand continues to increase. Uranium and thorium
together add up to some half to one trillion years of fuel
supply, at current nuclear-electricity generation rates. The
math is pretty simply, if we allow for some rounding errors.

Current uranium consumption is 65,000 tons per year.
http://www.world-nuclear.org/info/reactors.html

Current economically-minable-with-current-technology (without
breeder reactors) uranium totals some 40 trillion tons.
http://nuclearinfo.net/Nuclearpower/UraniuamDistribution

Richard Garwin estimates that breeder reactors would extend
supplies 60-fold. That would bring consumption down to 1,000
tons per year. 40 trillion tons / 1,000 tons = a 40 billion
year fuel supply. Add 160 trillion tons of thorium, and the
fuel supply becomes 200 billion years. Double the current
nuclear-electric thermodynamic efficiency of 34% to 68%, and
the fuel supply doubles to 400 billion years. Nudge up the
efficiency another 20% to 82%, and the fuel supply becomes a
nice, even half-trillion years.

If we use, instead of Richard Garwin's 60-fold breeder-induced
fuel-supply extension figure, Bill Hannahan's...
http://www.nuclearcoal.com/energy_facts.htm

...120-fold figure, the Earth's fission-fuel supply comes to
one trillion years worth.

It would not actually last that long, of course, since the
half-lives of the fuel isotopes are:

uranium-235 700 million years
uranium-238 4.5 billion years
thorium-232 14.1 billion years

Even if the thorium supply were tapped for most of, say, 20
billion years, the earth would likely have to be moved to
make way for an expanding sun.

In reality, breeder reactors will probably not be "needed" for
many hundreds or even thousands of years, even assuming
continuous upward demand for fuel. The breakeven uranium price
is currently thought to be some $1000/kg of mined uranium.
Below that price, breeder reactors do not make economic sense.
Even the current artificially-inflated spot-market price of
$60/lb = $132/kg is not nearly high enough to justify breeder
reactors.

http://www.cfr.org/publication/14705/global_uranium_supply_and_demand.
html

Thanks for the link.

As to why all mineral prices ultimately trend toward zero,
there are some theory explanations here:
http://www.juliansimon.com/writings/Ultimate_Resource