Atomhörnchen · @NeilBrainstrong
11th Sep 2011 from Twitlonger
@focusfusion I just did a nifty little back of the envelope calculation concerning the aneutronic #fusion reaction p + 11B -> 3 4He + 8.7 MeV.
In each ton of seawater, there are 4.4 g 11B. (Source: http://www.webelements.com/boron/geology.html)
Of these, 81% are 11B.
Mass of the World Ocean is 1.332 * 10^30 t. This corresponds to:
1.332*10^30 t * (0.81 * 0.0044 kg/t) = 4.75 kg of 11B.
Which again gives a number of 11B atoms of:
4.75*10^27 kg / (11.01 * 1.66 * 10^-27 kg) = 2.6 * 10^53
If we extract 10% of these (2.6 * 10^52) and each reaction gives an Energy amount of: 8.7 * 1.6*10^-19 J = 1.4 * 10^-18 J,
and the energy is split between 10 billion people and distributed over 5 billion years (~1.6 * 10^17 s) - until the sun turns into a red giant - each person can use as much as:
(2.6 * 10^52 * 1.4 * 10^-18 J) / (10^10 * 1.6*10^17 s) = 22.75 MW.
This means, using the aneutronic boron reaction, everyone on earth (assuming 10 billion people) can use 22.75 MW individually until the earth is burned to cinders by the expanding sun.
For comparison: Presently, in Germany the individual primary energy consumption is around 6000 W, in the US 11000 W and in the Arabic Emirates around 22000 W.