> US estimates of another 200 years of fuel

The world has a half trillion years' worth of fission fuel, at current
nuclear electricity production rates.

The world currently uses 64,615 tonnes of uranium per year.
http://www.world-nuclear.org/info/reactors.html

The world has 40 trillion tonnes of uranium.
http://nuclearinfo.net/Nuclearpower/UraniuamDistribution

Combined with thorium, the world has 200 trillion tonnes of fission
fuel.

200 trillion tonnes fuel / 64,615 = 3.1 billion years of fuel.

The use of breeder reactors would drop the yearly fuel use to 1,000
tonnes/year.

200 trillion tonnes fuel / 1,000 = 200 billion years of fuel.

The thermal efficiency of current reactors averages 34%.

Raise efficiency from 34% to 68% = 400 billion years of fuel.

Raise efficiency from 34% to 85% = 500 billion years of fuel.

> The world currently uses 64,615 tonnes of uranium per year.
> http://www.world-nuclear.org/info/reactors.html

Let's add some realistic growth to that shall we? 6.4 million tones use per
year in a few decades time if everyone turns nuclear and Chjina and India
continue trying to match US living standards. And they won't have much
choice unless alternatives have been developed. I'd like to believe that
such nations would be able to break lockstep with Us technological
docterine, but they've yet to demonstrate the capacity to throw off their
crippling lack of confidence in that area.

Question for the class: What percentage of this projected annual fuel usage
would we need to lose track of to allow terrorists to build a few crude
bombs?

> The world has 40 trillion tonnes of uranium.
> http://nuclearinfo.net/Nuclearpower/UraniuamDistribution

The world has even more hydrogen! Why don't we use that to run our cars! Oh
wait...
Estimate total geological capacity of the earth's crust has nothing to do
with how much is politically, economically, and safely accessable. And you'd
sound a little more credable if you didn't keep quoting from such biased
sites.

"Daz White is the best washing powder in the world! How do we know? Their
own website says so! So it must be true!"

> Raise efficiency from 34% to 85% = 500 billion years of fuel.

Actually, forget credability if you think this is even remotely possible.

From Nuclearinfo:
The total abundance of Uranium in the Earth's crust is estimated to be approximately 40 trillian tonnes.

,,,and from Wikipedia:
The oceanic crust is 5 km (3 mi) to 10 km (6 mi) thick[3] and is composed primarily of basalt, diabase, and gabbro. The continental crust is typically from 30 km (20 mi) to 50 km (30 mi) thick.

At the boundary with the lithosphere, the temp of the surrounding rock rise to 500 to 1000 degrees Centigrade.
No known material could even BEGIN to withstand the pressure of the overlying rock at anywhere near those depths and temps.

From NAtional Geographic:
The ambitious new mining projects are "ultra-deep" mines with shafts that are deeper than 2.2 miles (3.5 kilometers) in the ground, where temperatures rise well over a hundred degrees Fahrenheit (55 degrees Celsius) and rock shatters like glass.

There is only a limited amount of mass we can access on this earth. This is an unfortunate byproduct of gravity and limits to material strength. Thus the ACCESSIBLE uranium is far below what you posit and of course, you conveniently ignore the residual radioactive waste disposal problem,,,

The ONLY clean, relatively open ended power source we can readily access is solar and the most efficient way to do that is from orbit.

GAry 7