Hello! I hope you are all doing as well as possible right now. Since many of us are stuck inside for the time being, I’m going to try to revive this blog a bit.
For this first post, let’s talk about space-based solar power. The idea is a popular one; it is exciting (outer space!) and has some logic to it (there are no clouds, nights, seasons, or land-use-constraints in space!). Sadly, though, if you look into the topic – for example, if you read this very well-thought-out piece from Do The Math – you see that even with extremely optimistic assumptions, it seems unlikely that sending energy from solar panels located in space to earth will become economically worthwhile any time soon, if ever.
And yet, perhaps these analyses are missing something. From what I can see — with the huge, twin caveats that I haven’t looked too deeply into the subject, and that I understand almost nothing about the physics involved in it — recent discussions about space-based wireless power transmission have been limited almost entirely to the idea of generating power in space and sending it to earth in order to provide civilians with clean, reliable energy. There might, however, be alternative uses and methods for wirelessly-transmitting energy via space. For example:
- sending space-based solar power to military outposts, in order to provide soldiers with power that is not reliant on vulnerable supply lines, is not bulky to haul around from place to place, and is not intermittent. This is how I first heard about the topic of space-based solar power: George Friedman discusses it in his book The Next 100 Years.
- the same purpose as above, except that instead of the military outpost receiving power that is generated from space-based solar panels, it would instead receive power that is generated conventionally on earth, then ‘triangulated’: sent up to space, then back down to a different location on earth. Such a system could perhaps also work in tandem with space-based solar panels. Over time, for example, more panels could be launched, so that as the years go by the system would use more power generated in space and less power generated on earth. [Or, perhaps, if the system was located as an array of satellites in Low Earth Orbit (500-2000 km), rather than much further away in Geosynchronous orbit (40,000 km), having the system use power generated by earth-based sources might allow it to provide power 24/7, as would otherwise not be possible for a Low Earth Orbit system because Low Earth Orbit satellites spend about a third of the time being eclipsed by the earth, preventing any solar panels in such orbits from receiving sunlight at those times]
- Because wars are themselves intermittent, a space-energy system built for military purposes might be able to double as a civilian system during times when military demand is low. […Also, if the system was built as an array of satellites in Low Earth Orbit, rather than in Geosynchronous orbit, then each satellite in the array would only pass over a given military outpost or region on earth for a very short amount of time. Most of each satellite’s orbit in such a system might be freed up for civilian uses as result].
- There is also the question of how to provide satellites with energy, so that satellites themselves can be powered, both for military and non-military reasons. Militarily, for example, if satellites were to be physically attacked, it might perhaps be the case that their ability to protect themselves from any incoming projectiles would depend on whether or not they have more energy available to them than do the projectiles, which they could then outmaneuver. Thus it might be useful for satellites to receive power wirelessly, either from earth or from other satellites. And again, once such a system is built, it might also be able to find non-military uses, particularly since the military might not need to use the system much during peacetime. The system might then be available to power satellites for non-military uses. Or perhaps it could be used to power locations on earth
Obviously, I have absolutely no idea what I’m talking about here. So I’m asking, is there anything to these ideas? Are there other similar ideas that I’ve left out? How might these factors change the math when it comes to thinking about the future economics of energy in space?
Finally, if the civilians-piggybacking-on-the-military-surplus-capacity-of-triangulating-energy-from-earth-to-space-back-to-earth idea is anything other than totally ridiculous, which power sources would be best suited for it? Would solar panel companies in the Australian Outback benefit, for example, by being able to wirelessly send their otherwise-remote, Southern Hemisphere-summer energy to military and/or civilian locations in other parts of the world?