Space/Science — HabitableZone

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Nope...
Adam — (archived)

Hi EP

If you mean power it up there's no energy storage around that can pack enough in per unit mass to power a VASIMR for even a tiny bit of thrusting.

If you mean beamed power then there's plenty of opportunity especially with ultra-light weight inflatable receiver antennas - except they'd need to be really heat tolerant. Geoff Landis estimates that concentrator solar-generators could mass a mere 24 kg for 100 kW power using L'Garde inflatables and concentrator PVs (e~ 35%.) That's conservative since 70% efficiency may be around the corner. If so then your VASIMR could be powered by a big PV array - though probably not for launch, in which case they'd need a laser boost. A big one.

Personally EP I think Jerome Pearson's Lunar Space Elevator studies deserve a better look for Moon base needs. At liftoff it just needs 162 watts per kg mass for 100 m/s climbing speed - a Landis-style solar generator can lift 50 kg per kg of its own mass. More like 40 kg, accounting for inefficiency. On Earth it just won't happen on raw solar power alone because inflatables incur too much aerodynamic drag. Earth-liftoff needs booster lasers in a big way. A 20 ton ribbon climber needs ~ 4 MW on the Moon (motor e ~ 0.8), which is 4240 m^2 of collectors. Big! An acre of inflatables for a 20 ton climber. Sounds insane, but it masses just ~ 500 kg so it's doable.

Adam

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