Strategy to mine an asteroid, Part XIX

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Still thinking about this topic.  When I left off last time, I figured that getting the government to do this is probably unlikely.  It will have to be private sector and it will probably need something to hang your hat on, so to speak, to finance the startup of this thing.


Well, a thought came to me today, and there may be a way to do it.  Essentially, the space sail utilizes a mirror.  The mirror bounces the light off of it and that creates a reaction just as fuel does when it is burned in a rocket.  The thing about light is that the momentum of the photons is much less than that of matter.  So, you need lots of photons in order to generate any thrust worth mentioning.  That is why solar sails have to be so large.  There's momentum in a photon, but not much.  Since there's so little momentum, we can utilize the mirror to bounce the light back towards the surface of the earth.  Thus, we can use the mirror to make money on the ground before we take off for the asteroid.

By utilizing the sunlight from the space sail, we can speed up the growth of an agricultural product, or we can just make seaweed for biofuels.  The sale of the biofuels will make money for the enterprise.  It also occurred to me that if you were to sell carbon credits in a country that has a carbon market, you may be able to pick up some additional change.

I figure that within a few years of operating it as a biofuel making device, there will be enough earnings to outfit the space sail for its trip to the asteroid.  Getting the thing up there and built will take one rocket launch, most likely a Falcon heavy launch.  The rest of the equipment and construction will take a second launch.  The cost of two launches--- about half a billion.

Come to think of it, that's a lot of biofuel.  If you made a dollar a gallon, that be a half a billion gallons.  You'd have to obtain this from a patch of sea of 4 square kilometers.  Well, I figure the biofuels are worth more than the electricity would be worth, and it can produce enough electricity.  If it can produce enough electricity, I figure the biofuels would be enough.  It's a guess though, and the guess may be wrong.

Update:

The guess is wrong, most likely.  After some time to run the numbers, the amount of biomass that might be obtained this way will not yield enough revenue to make this plan work.  Evidently, biofuels are less efficient than photovoltaic cells.  That surprises me a bit.

Update:

A couple more points.  Seaweed is considered a type of algae.  So, in the numbers mentioned in the update above, the output from seaweed could be much higher.  Secondly, this source claims an output that might be worth considering.  That would be true even without the advantage of a space mirror which would turn production into a 24/7 proposition.  Bottom line:  don't rule it out yet.



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