[ExI] The L5 Society ( was: EP and Peak oil.)

[hkhenson]

At 05:37 PM 4/10/2008, you wrote:
>I've been following this thread for some time and have so far 
>managed to fight off the urge to comment. But I hadn't yet seen any 
>mention of protecting this trillion dollar behemoth from natural and 
>unnatural disasters. micrometeorites that our atmosphere eats up 
>could tear one of these to pieces. The chance is slim of course, but 
>the target is larger than most satellites

*Hugely* bigger.  One power sat would have more area than all the 
satellites that have been put up to date and getting hit by flying 
rocks is expected to be an almost hourly thing.  Fortunately most of 
them are tiny and are not expected to cause much damage--unless they 
hit where high voltages are adjacent and then there will likely be a 
flashover.  The subject was studied in great detail back in the late 
1970s and the researches concluded it wasn't much of a 
problem--largely because the structure isn't under much stress.

The space elevator, if we get materials strong enough for that, is a 
much harder problem.  There has to be a way to recover from a cut 
cable and to complicate it, the cable is zipping by at 1000 mph.  If 
you have any good ideas, let me know.  Because all satellites below 
the counterweight hit the cable eventually it will take a massive and 
very expensive cleanup of the space junk.  You do get to use the junk 
you clean up as mass for the counterweight though.

>  and when your one shot is worth that much money you would have to 
> find ways to make those odds even better, not worse. Also, your 
> rocket would have to been man-rated or better to provide that extra 
> level of caution. How many successful test launches would you 
> require of a new launch vehicle before you stick a 1 TRILLION 
> dollar payload on it?

You never do.  Using rockets, each launch delivers 200 tons of 
material.  It takes 50 flights (at ten a day) to build one power sat.

>How much more will these test launches and additional developments 
>cost? Wouldn't it make more sense to put hundreds or even thousands 
>of much smaller satellites into orbit?

It's a geometry problem, http://en.wikipedia.org/wiki/Airy_disk that 
sets the size of the power sats.  They just are not practical in 
sizes much less than 5 GW.  Work backwards from 230W/square meter and 
you will get the transmitter and receiver sizes.  Still the point is 
well taken:  there is such a need for power that the project builds 
more than a thousand of them, 60 in the first year.

>Then the loss of one isn't so dramatic and you could use profits to 
>bootstrap the project with much lower up front development costs.

In fact, the income stream builds the vast majority of them.

The startup cost are between the cost of the Iraq war and the value 
of a year of oil production.

Keith