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Economics of Space Settlements, Part II

Previously, I talked about why space settlement, using current technology, would cost too much to ever happen.  But what if the costs were to drop enough, through nanotechnology or some comparable magic wand?

Simple: the price of goods sold by space settlements would be too low to pay back even those new, low costs.  Why?  The same nanotechnology that lowers the costs of space settlement would lower the cost of finding or making those same goods on Earth.

Consider the Niven/Pournelle dream of asteroid mining.  (I cut my teeth on Pournelle’s science fact essays collected in A Step Farther Out.)  All it costs to bring thousands of tons of highly pure iron or nickel to Earth from the asteroid belt are the capital and operational expenses of round-trip travel and smelting.  At current nickel prices, those expenses would have to be less than about $9/lb of delivered nickel to pay off.  For iron, those expenses would have to be closer to $0.10/lb of delivered iron to pay off.  (Remember, using current technology, the expenses would be at least $1000/lb, if not much more).

Let’s assume nanotechnology can lower those expenses 10,000-fold.  It would do so by making both the machines to do the travel and smelting work, and the energy to drive that work, much cheaper than today.  So nanotech-using miners could settle the asteroid belt, ship nickel or iron to Earth, and make a profit, right?

Except for one thing.  Those lower expenses for smelting machinery and the energy to run it would also apply to Earth-based mining.  Reduce the costs of Earth-based mining by, let’s say, just 1000-fold, and iron and nickel deposits that today are too marginal to pay for themselves would become immensely profitable.  For that matter, mining landfills and salvage lots for the iron and nickel in junked appliances and cars would become immensely profitable.  I haven’t run the numbers, but I suspect it would be profitable under those conditions to extract iron at its baseline abundance of 5% in Earth’s crust.

Comparable reasoning would apply to essentially any element or compound.  Regardless of the state of technology, there’s nothing useful to Earth’s economy you could find or make in space you couldn’t find or make more cheaply on Earth.

But, but, strangelets!  Stringlets!  Magnetic monopoles!  Unobtanium!  Yes, there may well be exotic matter out there, but no one’s going to spend a large sum of money hunting for it.  What economic value would it have?  And if it had any, would it be cheaper to substitute for it using terrestrial materials?  The answers very much seem to be “none” and “yes,” respectively.

So, Raymund, there will never be human settlements in space?

I never said that.

But you spent the last two posts stating that human space settlements make no economic sense and never will.

True.  But that doesn’t mean human space settlements will never happen.  I’ll get into the reasons why they might happen in my next post.

Economics of Space Settlements, Part I

As a longtime sf fan, one of the toughest realizations I ever came to is that Space settlements will never happen for economic reasons.

In part, the costs of getting to space are too high.  Charles Stross has discussed the costs at great length here.  To get one person to the Moon, bringing along the life support he needs for the trip, using advanced versions of the rocket technology we have today, would cost about US$400,000 as an optimistic estimate.

That’s far too expensive for anything except government boondoggles or multimillionaire’s larks, i.e., the current state of space travel.

Things get worse as go further in the solar system, even keeping in mind Heinlein’s comment that “Earth orbit is halfway to anywhere.”  The cost of travel to Mars or any other place in the solar system would be even higher than $400,000, for at least two reasons: (1) you have to carry the fuel for the return trip, and (2) you have to carry more life support infrastructure for the years of round-trip travel time forced on you by Hohmann transfer orbits.

Interstellar travel?  Alpha Centauri is about 250,000 times further away than Mars.  The energy cost to get a solitary explorer there in less than one lifetime (at 0.1 c, 40 years in transit) is comparable to the yield of all nuclear weapons ever built, or the energy consumption of the entire world for a couple of weeks.  Generation ships are even worse:  the energy savings from their slower speed (call it 0.01c, 400 years in transit) is offset by the mass of hundreds of people and the infrastructure needed to keep them alive and safe for four centuries.  And we haven’t even touched on the individual and social psychology issues these avenues would bring up.  How well would you do living in your car for four decades?

So nevermind settling the solar system; the idea of normal people going into space is so expensive, it’s a non-starter.

About now, a reader might protest, “But what about nanotechnology?  Advanced materials and cheap energy production will lower all those costs dramatically.”

I read Stan Schmidt’s mid-’80s Analog editorials on nanotechnology, and K. Eric Drexler’s Engines of Creation.  Although I think Drexler is intoxicated with his ideas, I completely agree that some of the fruits of nanotechnology–the super-strong, super-light materials and cheap energy referred to above–are entirely possible, and are in fact likely to appear somewhere on Earth in the coming decades.  Yes, those advances will make space elevators and fusion-powered torchships possible.  Yes, nanotechnology would greatly lower the costs of space travel and space settlements.

But.  Nanotechnology would also greatly lower the benefits of space settlement, leaving the prospect as uneconomical as it is today.  More on that point in my next post.