Jul 252011
 

In 1978, Boeing cranked out a whole lot of information – reports, presentations, artwork, etc. – on the Solar power Satellite concept. The idea was that giant satellites covered on photovoltaic arrays would be built in low Earth orbit, then moved up to geosynchronous, where the power generated would be converted to microwaves, beamed to Earth, captured and  converted back into electricity. The idea was grand, it was bold, it was forward thinking and it was doomed. In the early 1980’s the price of oil collapsed from its OPEC Oil Embargo days, and the support for such vastly expensive schemes as SPS vanished.

It was not inevitable, of course. A few minor tweaks to the timeline, and the Arab oil producing states might have kept the cost high: either through simply controlling the price, or by the simple expedient of warfare blasting the crap out of the oil fields. Had oil stayed high, who knows… SPS might’ve become the growth industry of the 1990’s.

Boeing was one of the major companies looking at the SPS concept. Each SPS would be roughly the size of Manhattan, and would produce around ten gigawatts. Hundreds of launches would be required to transport the raw materials to orbital construction bases… and hundreds of workers would be needed in both low Earth orbit and geosynchronous to oversee construction.  Boeing mapped out the probable timeline of populations on-orbit. The assumption was that two SPS’s would be built per year; this constant rate of construction is reflected in fairly constant numbers for the construction bases in LEO and GEO; the constantly increasing number of satellites explains the increasing number of maintenance crew. 20 SPS’s would require 1000 crew; 40 would need 1400 and 60 would need 1800.

A whole lot of the assumptions regarding SPS seem sadly laughable from the vantage point of the post-Shuttle years. For example space transport was seen as needing to be incredibly  cheap, with blisteringly fast turnaround times and a launch of a heavy lift booster (such as the Space Freighter) every 21 hours or so, for decades on end. Even had those succeeded, the crew numbers are almost certainly far too low. Not only would construction and maintenance have turned out to be a lot harder than hoped… there would be a lot of people not considered in these simple analyses. If you have a construction base that lasts for years… you are going to have families. And people who provide goods and services not only to the crew, but to their families. And the tourists. And the scientists, engineers, bureaucrats and everything else. Without setting out to do so, the SPS concept could easily and necessarily have led to populations in Earth orbit measurable in the thousands to tens of thousands.

Had work begun on SPS in earnest in 1980, the first flights might have started in 1990 or so. By which point we’d be two decades into the project. Assuming they kept on schedule (ha!), we’d now have at least 40 SPS satellites, each providing 2.5 gigawatts of net electrical power. That’s 100 gigawatts; over a year, 876,000 gigawatt-hours. Energy usage in the US today is about 29 petawatt-hours = 29,000,000 gigawatt-hours. Thus… a whopping 3% of todays American energy needs could be filled by twenty years worth of solar power satellite construction. Meh. One could always assume that twenty years of technological advancement might’ve improved the efficiency of the solar cells and the transmission systems, bumping up the net power produced by a satellite; still, it’d take a whole lot of satellites to make a real dent in Americas energy needs.

 Posted by at 11:29 pm

  8 Responses to “On-Orbit Crew: what might’ve been”

  1. Here’s the giant bruiser of a rocket that Boeing was going to use to haul all the stuff into orbit:
    http://www.pmview.com/spaceodysseytwo/spacelvs/sld043.htm
    This thing would have been so loud on liftoff that it would make a Saturn V seem almost quiet by comparison.

  2. “America’s energy needs”

    I’d suggest the last word of your post is where to look first. There’s needs, and then there’s gluttony.

    • Well, sure. We *could* use the SPS’s to generate laser beams rather than microwaves, in order to burn down enemy cities, to wreak horrible devastation upon those who dare oppose us, but I suppose that’d be just kinda greedy. What about the poor nuclear industry? They’d be left out in the cold… all that work developing hydrogen bombs, and nobody bothers to use them. Spread the love! Nuke an enemy nation today!

      Unless, of course, you’re referring to the idea that Americans use too much electricity. in which case the answer is obvious: start with major metropolitan areas such as LA and New York City. Cities that pass gun control, speech code or land use laws that are more stringent than state laws have de facto admitted that their subjects are less worthy of basic human rights; consequently, it should be a straightforward enough matter to simply ration energy usage. Let’s start off with, say, 2400 watt-hours per day per person. That’s enough to run a 100-watt light bulb all day long… more than enough for a loyal subject! If they turn off the light for some hours every day, that might even be enough to let them ride the electric bus for a few blocks every few weeks.

      • It’s not a libertarian vs state argument, it’s a human argument. We all gotta share this blue marble and y’all are using way more than a fair share or even a sustainable share, which is a root cause for misery in this world. Human rights aren’t free; they come with responsibilities.

        • > We all gotta share this blue marble

          No, we don’t. It’s a profoundly ignorant view that Earth is all that there is.

          > and y’all are using way more than a fair share

          Hardly. Look at the total output of the Sun, and compare that to the miniscule amount used by the US.

          > or even a sustainable share,

          Hardly again. The amount of energy available in the form of coal or uranium dissolved in seawater is truly immense. Never mind the amount available in the form of solar power. But I suppose if the US paved the moon with PV arrays and met all our needs and, better, *wants* with electricity beamed down from the moon, eliminating our dependance upon fossil fuels, people would *still* bitch and moan.

          As to your link: it provides power consumption in the form of kilowatt hours per year. But what it *doesn’t* do is provide any meaningful context, such as *productivity* or standard of living per kilowatt hour per year.

          > Human rights aren’t free; they come with responsibilities

          Indeed so. And one of those responsibilities to to grow the hell up and not try to enshrine jealousy as a part of international diplomacy. If people in the US are living better than you, rather than trying to knock us down to your level, why not try to climb up to ours?

  3. I seem to remember Dwayne Day talking about an Osiris Rex platform. With SLS, the Direct/Ares V type HLLV, Orbital Antenna Farm (OAF sadly) and Space Based Radar might finally get some love. Any data on those?

  4. Any chance we can get copies of the Boeing SPS presentations? Will have to google Osiris Rex platform and OAF, both sound interesting. Thank you Mr. Wright.

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