From HomoExcelsior

Josh Hall of the Foresight Institute proposes a string of 100km-high diamondoid towers bearing a 1000-km long maglev launcher capable of 4-gee acceleration to orbital velocities and faster. While Hall envisions a Florida location, the Equator would be preferable. The electrical energy of orbital insertion is 8 kw-hr per pound, roughly a dollar at retail rates, but the peak power at 8km/sec is 145kW/pound or 7000 pounds per gigawatt, so that enormous power generation would be required for even a bizjet-sized spacecraft.

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