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A comment on Why Bezos’ rocket is unprecedented–and worth taking seriously. Parent comment

Re:Why Bezos’ rocket is unprecedented–and worth taking serio... by dsp1234 on Tuesday September 13, 2016 @01:13PM (#12490265)
According to this document from the USAF, the estimated energy needed to launch into orbit is 67GJ. Converting that to the US measurement of electricity is 18,611 kWh. According to the EIA, the US average for electricity, specifically for the transportation sector, was 10.22 pennies per kWh.

So yes, a lot of pennies...

edit: The same document mentions that 20 degree launch trajectory gives LEO == HEO delta-v. So that 200km track also needs to, naively, be 72km high at the end to have constant acceleration through that 200km.

[0] - http://www.star-tech-inc.com/papers/lcls/low-cost_launch_2.p...

[1] - https://www.eia.gov/electricity/monthly/epm_table_grapher.cf...

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Re:Why Bezos’ rocket is unprecedented–and worth taking serio... by dogma1138 on Tuesday September 13, 2016 @01:19PM (#12490330)
That's 67GJ per KG? because otherwise either I'm very very wrong, or they are very very optimistic.
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Re:Why Bezos’ rocket is unprecedented–and worth taking serio... by dsp1234 on Tuesday September 13, 2016 @01:26PM (#12490391)
Looks like that's for a 300kg total weight projectile @ 20% energy efficiency. Details can be found on page 317-318.
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