SBSP still cannot scale (was Low cost power sats)

> Estimates of growth in electric power needs over the next 40 years are in the range of 3.4%/year.That's a doubling time of 21 years, ie 160 tera watts in 63 years

World electric-power generation in 2005 averaged 2 terawatts, not 20 terawatts.
http://www.eia.doe.gov/oiaf/ieo/electricity.html

At 20-fold/century growth (3.04% annual), that 2 terawatts would become 6.4 million terawatts in only 5 centuries. Terrestrial nuclear power can handle this growth. SBSP, because of orbital real-estate limitations, cannot.