I was reading a July 2015 article from "The Ion Project" on Solar Power Satellites (here it is) and wanted to comment on it, but of course there was a severe character limit on the comment form that forces folks to reduce their thoughts to sound bites AND the author didn't provide an alternative way to get in touch... so I'm putting my response here and eventually when I track him down I'll have it.
Dear Mr. Manning,
An excellent post hitting on many of the most important points. There are different perspectives to some of the bullets that should be kept in mind including:
1) Mr. Musk is the owner of an Earth-based Solar energy company, and because some speculate that his core reason for SolarCity is to make a bit of money while being on the cutting edge of cell technology for his Mars-travel craft and eventual Mars-based needs it does seem to add up that his company would offer a valuable opinion on SPS.
But expand that view a bit and consider that taking up work on or even just admitting publically that there is even a small reason to put thought into SPS would detract from his primary goal of getting to Mars. If a business person admits that there is a need to put a portion of investment into a related product, but not the specific one that they are directly setting out to produce, then it could affect their investors' dedication.
Mr. Musk has a big project on his plate and the vast majority of people do not understand it, even if they are investing in it right now while it is "hot"; He needs to stay on his message and keep his politically minded fans and his potential investors fully on HIS target.
This is in no way a negative reflection on him... he is doing amazing things, but he personally - and in the role of the face of his companies - is working on getting to Mars, which is a goal that is less helpful to ALL humanity than setting up a way to get energy to help the developed nations on Earth continue to have technological growth and less-developed nations get the energy they need to get their own Industrial Revolutions (and potable water needs and agricultural needs - both HUGE users of Electrical energy) moving forward.
With a goal that is not as directly related to the Humans that will be left behind him on Earth, he has a tough daily agenda full of meetings to keep the Mars-Only idea hip and cool and exciting. SPS is not going to be something he promotes even if he does actually see any good reason for it. His eyes are, as they *have to be*, only on the needs of his shipmates on his trip to Mars.
2) Launch Costs. This has been the easiest to comprehend restriction since the 1970s. However, you did mention Gerard K. O'Neill so it is worth mentioning that O'Neill was never behind lifting the dumb mass (the 97+% of the needed mass, excluding the actual high-tech components) of such a system from the Earth. He and his students and the Engineers who have been researching and working on "The High Frontier Concept" since 1974 have always clearly stated that if you have to launch the overwhelming dumb mass for any large structure (SPS or habitat worth living in) from the Earth then it was an impossible task for the foreseeable future and even beyond.
He states that very clearly in the 1976 and 1988 editions of The High Frontier... and here is a quote from him in 1992:
"It is neither practical, nor economical, nor environmentally acceptable to lift from the Earth by rockets the thousands of tons of materials needed to build an SPS that would supply Earth electricity equal to the output of ten nuclear power plants."
That point, known and acknowledged from the very start of the idea, was the reason for the research on and real-world working demonstration models of Mass-Drivers. The dumb mass was never envisioned to be dragged up through the Earth's gravity well, it was to come from Lunar sites, and passed up to free-space for processing.
This is a key to the knee-jerk lock that SPS has had on its governmentally funded research... for all the decades that fusion research has had few issues finding its funds - even while for all of those decades that technology has always remained "just 10 or 20 years away" - or as Bullwinkle has described it, over the same amount of time and with the same undiminishing enthusiasm: "This time for SURE!"
HOWEVER, while direct government funding can be a nice thing, adding some credibility that investors who are not close to a technology look for when they put their own money into very large-scale product development, it also has its bureaucratic and 'political-winds' downsides. So I am very, very happy to have read your sentence:
"In this context the most prudent way to proceed is with more experiments so that a clearer understanding of the practical issues involved can be acquired."
O'Neill was, and The Space Studies Institute, the organization he founded, *is* behind that statement 100%. Just as The High Frontier Concept is about Humans - regular human folk, not just gods who have the superhuman right stuff - having the option of living and working in Space, SSI has always been about encouraging regular folk - people with multiple Engineering degrees and just us Joes and Sallys with a passionate desire and a basement workbench - to roll up their sleeves and make part of the puzzle that can be demonstrated to the "Experts" who don't yet "get it." And who won't until they see it.
O'Neill talked about Storage Ring Technology being a great way to improve particle accelerators and the experts said it was not possible in the real world.. so he went to the laboratory and came out with a working model and a patent. And now Storage Ring technology is a fundamental part of most every high energy lab and accelerator in the world. O'Neill knew that people had to make and show, not just rant and rave.
And even when such working models of a concept don't end up working, they offer more data and information that will add up to making SPS and "space for everybody" eventually possible.
Where do Joe and Sally start? O'Neill offered this:
"Transmission is the question that deserves continuing research: How to send the lowdensity radio waves from an SPS to antennas on the Earth. I have satisfied myself that transmission does not involve significant risks. But I invite you to do your own research. One of the best sources on the subject is The Microwave Debate by N.H. Steneck (MIT Press)."
That was in his last article, published in 1992. If he were alive today, I think he'd suggest SSI Senior Advisor John Mankins' "Case for Space Solar Power" as a good place to start reading.
But reading is only the beginning - *Making* is what will get the job done. If plumbing or greenhouse design or getting the absolutely most powerful telemetry signals from their personal hobby drones is a person's passion then there's a idea that could add to the effort sitting in front of them too. They should work on it and document their findings beyond the small group of friends sharing just their niche interest, showing it to others involved in the bigger picture - such as letting O'Neill's SSI know about it.
Thank you so much for your post.