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0 pointsaerovistae9y ago0 comments

I suspect Tesla will move into aircraft and oceancraft in the long-run, if you're interested in "other industries." He's mentioned the electric jet enough times. And why would he create a new company for it when he's got all the expertise and business structure at his fingertips already?

Solar harvesting in space sounds really cool, but how do you get that power back to earth? Even if there were a way, it's not necessary or effective. He's said very clearly that you could just have a giant square of solar panels in the desert and it would power the whole country. Why bother putting them in space? No advantage.

However, SolarCity IS likely to provide the panels for SpaceX's satellites, of course. So there is that form of solar harvesting in space.

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dingaling9y ago

> Solar harvesting in space sounds really cool, but how do you get that power back to earth?

This has been investigated several times and the most promising technique involves using maser downlinks to transfer the energy.

> He's said very clearly that you could just have a giant square of solar panels in the desert and it would power the whole country.

Ok that's a start. That takes care of the energy needs of 3.5% of the Earth's population, once they have sufficient storage capacity to see them through the night.

Geostationary space-based solar collection can work 24 hours per day, with much higher efficiency and minimal storage requirements, right over the areas of peak demand even when the ground is obscured by rain and cloud. No deserts required.

ams61109y ago

If there were a way to collect additional solar energy in space and somehow get it back to earth, that is now a net increase in energy, which will ultimately end up as heat, being delivered to the planet. At a large enough scale and over time this would be a global warming contributor.

Solar power collected on earth is just using energy that is already being delivered to the surface -- no net change.

jnicholasp9y ago

At some point we will need to take an active part in regulating the planet's weather and various climates. Orbiting solar panels on orbits that pass between us and the sun, that can be selectively turned edge on, or perpendicular, to the sun, would let us control solar influx to particular surface regions, limiting energy input in specific places while also harvesting that energy and enabling us to put it to use as needed without increasing total energy/heat input.

makomk9y ago

Satellite solar panels are very specialized devices that use different technology from ground-based ones. For a start, efficiency is much more important on satellites because of space and weight limitations, so they're generally multi-junction gallium arsenide solar cells rather than the cheaper single-junction silicon used in ground-based solar power.

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