Brin-l Digest, Vol 376, Issue 5

[hkhenson]

At 12:00 PM 4/11/2008, Alberto wrote:

snip

>Maybe even if launch costs were _zero_, orbital power satellites could
>still have a negative energy net production. Last time I heard (when I
>was working in the Space Industry, and not in the Oil Industry), solar
>arrays required more energy to be built than the energy they produced
>during their lifetimes.

It's under a decade now.  But if you take the same cells into space 
and just do a mild 3 to one concentration, you get more than a factor 
of ten more energy out than you do on the ground.

>Alberto 'oil rulez, fsck space!' Monteiro

Completely correct.  But what do you do when you run out of oil?  Try 
this web site.

http://www.drmillslmu.com/peakoil.htm

The part on what it takes to replace the cubic mile of oil per year 
we are now using is instructive as well as the concept of net energy 
which you mention.

Keith