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How Space-Based Solar Power Plants Could Be Built By Robots On the Moon (blastingnews.com)
MarkWhittington writes: The concept of space based solar power has been around for decades. The late Gerard K. O'Neill proposed building them as a way to finance space colonies in the 1970s. Recently Popular Science reported on a modern approach to building space based solar energy stations. Instead of relying on massive, orbiting space colonies filled with construction workers to put the plants together, why not automate the entire process?
Where is Solaren's 2016 installation?
https://en.wikipedia.org/wiki/...
Oh, not even a single bolt in orbit yet? Oh I guess it'll just magically happen in the next nine months?
These space fantasies always follow the same pattern:
1) Uncritical support from people raised on sci-fi and proficient in software, but with no knowledge of the physical sciences and engineering
2) Failure to deliver anything
3) Upping the ante to ever more ridiculous concepts
Given that its been quite a while since someone landed anything on the moon. It would be a victory for space exploration if someone sent up a robot and dug a hole. People in the 60s would have expected a decent size lunar colony by now
I'm sure the instant someone can make more selling electrons generated from orbit than it costs to produce them (without siphoning tax dollars off of the rest of us clods), you'll see such a business materialize, the world will be a better place, oceans will stop rising, etc.
Until then, let's continue with the research but utilize what's the most cost effective now.
Fer God's sake, fusion energy is just around the corner... :)
An object in space beaming energy down to a planet. Sounds a lot like a Death Star to me.
As for self-replication, that would be a neat trick to master just on earth and is probably still a long ways off; but once we do, it works just as well on Earth. Furthermore, the moon is still a fairly deep gravity well; for any kind of orbital construction, it makes much more sense to divert an asteroid into orbit and use that as the raw material for solar panels, space stations, or whatever, rather than launching from the moon.
> "The problem with regular solar power is that the sun isn't always up." (from the article)
This problem exists on the Moon too. It makes sense to get raw materials from the Moon, but not to put your factory there. It takes about 900 MJ to produce a square meter of silicon solar panel, and their output is about 245 W/m^2 in space. So they make back the energy to copy themselves in 3.67 million seconds, or 42.5 days. Typical working life against radiation damage is 15 years, so the panel can copy itself 128 times in orbit away from the Moon, but only 64 times on the surface, where sunlight is available 50% of the time.
Space Station era space solar panels had a power output of 55W/kg, so a square meter has a mass of about 4.5 kg. Kinetic energy of escape from the Moon is 2.83 MJ/kg, so launching the materials for the solar panel require 12.75 MJ/m^2. The panel in orbit can make back that energy in 14.5 hours, so the extra energy to launch the materials is small compared to the 7.5 years of extra output you get.
Automation was nowhere near as good in the 1970's as it is today, so by all means use automated factories. But put them in high orbit so they get full-time sunlight to operate with. The Moon and Near Earth Asteroids serve as sources of raw materials to feed the factories. The reason you want both is the various asteroid types have different compositions than the Lunar surface and each other. So you get a wider range of materials to work with. In particular, some asteroid types are nearly pure iron-nickel alloy, and others have lots of carbon and water. Those are not easily obtained from the Moon, and any mining engineer will tell you to go for the highest grade ore, because it's less work to extract the product.
There was a NASA paper about the manufacture of solar cells on the moon part: http://ntrs.nasa.gov/archive/n...
--and, now that I look at the NASA site, also this one: http://ntrs.nasa.gov/archive/n...
And how exactly are we going to get this energy back to Earth? With the Simcity 2000 cityzapper?
The comments of someone who knows a thing or two about the economics of space transport: "While Musk loves electric cars and spaceflight, there's one thing he hates: space solar power. "You'd have to convert photon to electron to photon back to electron. What's the conversion rate?" he says, getting riled up for the first time during his talk. "Stab that bloody thing in the heart!""
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Um, if we manage to figure out how to 'wirelessly beam' energy over great distances with an efficiency that's anywhere near useful, and if we manage to solve the problem of what happens when a satellite or an airplane or a flock of birds or whatever flies through the beam, then maybe it'll be time to talk about automating the building of solar power plants on the Moon.
OTOH, if we manage the sci-fu and eng-fu to accomplish those things, maybe we can just efficiently generate and distribute cheap solar electric power right here on Earth, and forget about space robots and moon shots. Just a thought.
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
Sure, and B.o.B says the earth is flat. I'm not buying from either the rapper or the fortune teller.
Bonus points for why "wirelessly beam[ing]" planetary scale power isn't a good idea. The article ignores the problem of how that even happens, or how a small targeting error doesn't take out Manhattan.
"National Security is the chief cause of national insecurity." - Celine's First Law
How can a carbon based biological organism compete?
Why is Snark Required?
The referenced paper says that to meet our energy needs through solar power alone we would need an area 92% of Nevada covered in solar cells. Nevada is 286,367 square kilometers in area. 92% of that is about 286,000 square kilometers. There are an estimated 1.7 billion buildings on planer Earth (see https://github.com/svendvn/sam...). If their combined area is less than the area needed for solar cells to power Earth then their average floor space area is less than 168 square metres each (about 1,700 square feet each). A 13 metre (43 foot) square building beats that. Sure, our power needs keep climbing as our population increases. So does the number of buildings required to house and service the extra people. Solar cells are too expensive to put on every roof today, but Moore's law applies. Standard roof tiles will one day come with some level of photovoltaic capability baked in.
Therefore, it too will receive day/night cycles because a geostationary orbit can only occur at the equator.
Er, no. There's a reason that lunar eclipses are rare and only happen at two times during the year - a satellite that far out would rarely be "behind" Earth, and even then most of the year it would miss Earth's shadow by being "above" or "below" it since the Earth is tilted on its axis.
Plus there's no reason that multiple independent satellites couldn't be used to power a given area, all at a different angles - when one at a time gets eclipsed it's not a big deal. And there's no reason they need to be geostationary - if their orbits tilted at different angles (i.e. once a day, but not directly over the equator) they'ed get eclipsed at different times of the year.
Perhaps a silly question but something that must be worked out, this base needs power but the sun sets on the moon just like it does on Earth, is this moon base solar powered too? If so then what do they propose the base do while the sun goes down for something like 400 hours?
I suppose the base could be placed on one of the poles, that would give it 24/7 daylight but I suspect this messes with the launch of the solar collecting satellites. I'd expect that a launch from the equator would take less energy than a launch from a pole. If there are three or more solar collectors on the equator, spaced somewhat evenly, and connected with long wires, then it could get 24/7 power. At that point it might be easier to have a polar power station and an equatorial launch station, again connected with long wires.
What else could power this moon base? Even if there was coal or oil on the moon there's no oxygen in the atmosphere to burn it with. There's no flowing air or water to derive energy from. What else is on the moon for energy? Uranium perhaps? Thorium even?
They'd be digging up all kinds of rock to get out things like iron, aluminum, and silicon. So what's left over? Well the processing of the rock for the solar panel material already gets you at least half way to extracting the fission fuel. Why not harvest that for energy too? Sounds more productive than building a trans-lunar power grid. It would also mean more solar panels launched instead of being used to power the base.
Another question, how much energy does it take to launch something to Earth orbit versus launching it to the Earth's surface? I'm curious since if we are extracting this fission fuel, and we have a launch system that can carry large solar arrays, there might be some left over thorium that can be dropped to Earth. Solar panels in orbit might be more efficient than those on Earth but Earth based nuclear power plants work much better than those in orbit.
Another question, aren't moon rocks a lot like Earth rocks? They'd have similar compositions as far as content of nickel, iron, silicon, and thorium, no? We'd have to build robots that can dig up rocks, extract the minerals, sort them out, and form them into parts suitable to create things like solar panels, rockets, and more (for growth or just replacement) robots. Why not just use these robots on Earth to build solar panels on Earth? The thorium and uranium they extract as byproducts could be used in nuclear reactors. We'd also be able to skip the step of building rockets and rocket fuel and simply build more robots, solar panels, and nuclear reactors.
These Earth based solar panel making robots would not need to be completely autonomous since they'd be easily accessible to us fragile humans that can't work on the moon without a habitat or cumbersome protective suits.
One last question, what do they propose these lunar robots use for rocket fuel? The stuff we use to launch rockets from Earth tend to be based on petroleum. These rocket fuels might be in the form of kerosene, derived from petroleum, or hydrogen, typically derived from natural gas. These fossil fuels do not exist in vast quantities on the moon. Even hydrogen derived from hydroxide minerals would be difficult to obtain. The rockets could be nuclear powered and use a variety of gases for the working fluid, that might cut down on the mining required for rocket fuel. Getting enough gases to use as a working fluid is likely problematic on the moon as it has no atmosphere to speak of.
I have to wonder how much actual thought was put into this proposal.
I am armed because I am free. I am free because I am armed.
The radioactive waste issue is also a solved problem, the only reason it is viewed as a problem today is because we have backward laws on how to deal with radioactive material
No it isn't. There are extremely complex geological problems that have to be solved so that the radioactive isotopes don't end up in groundwater.
and because we have not yet built a truly modern reactor. We've been building what is basically the same backward reactors for 60 years.
The reactor you speak of, IFR, was funded, built and is now budgeted for complete destruction in the 2005 Energy act which also contains budget for building the reactors that you speak of that are the same as IFR (Sec 600 onwards) and no organizations are accessing that funding. So it is extremely unlikely that these reactors will ever be built commercially.
My ism, it's full of beliefs.
"The concept of space based solar power has been around for decades"
The IDIOTIC concept you mean. Anyone with a calculator, let alone Google, can demonstrate how RIDICULOUSLY MORONIC this idea is. Sorry for the caps, but in this case that are appropriate. Here, try it yourself:
https://matter2energy.wordpress.com/2012/03/17/the-maury-equation-redux/
https://matter2energy.wordpress.com/2014/02/25/lunacy/
I don't have anything to add to the debate other than to say that that is an awesome headline. It was awesome enough after "built", then even more awesome by the inclusion of "Robots" then to just go completely mad it added "Moon" - Robots on the Moon! My head just exploded
"How Space-Based Solar Power Plants Could Be Built By Robots On the Moon"
Best headline ever.
So they're proposing robots only? You tender little humans, let me pat your hand, sit there in the shade, and we'll take care of everything...
Screw that. Put people up there, hell, there's be plenty of jobs, including the crowd control and refreshments for those of us in line to go.
mark "what's here for us (pointing to the GOP)?"
Robots on the moon deserve a decent moon living wage of 15 Lunar Credits an hour.
Rise up! You have nothing to lose but your chains!
-- Tigger warning: This post may contain tiggers! --
That we don't have ....
And are very unlikely to have for the forseeable future.
And if we had replicators, we could probably pull tricks that'd make death rays in orbit unecessary anyway.
There is no truth to the rumor that we have death rays in orbit.
It cost too much and they were too unreliable.
-- Tigger warning: This post may contain tiggers! --
If we develop practical self-replicating robots (since we can 'almost' do a proof of concept self-replicating one now)
If we develop technology to plausibly 'mine' surface material (i.e. moon regolith) that's not more involved in shipping material
Bonus if: If we can make both happen in a hard vacuum where no one has set foot in decades
Extra bonus: if we can prove out transmitting GW (much less TW) power from geo-stat orbit
Then of course let's do this. In reality this sounds like any of a dozen sci fi books I've read. Send magical self-replicating robots off to do some job and let them multiply. I'm surprised they didn't include nano-something to make it even more gooder.
Any major aspect of this project would be easily be worth many times over the $350 projected cost.
You can get rich if you own a politician, but you have to be rich to buy one in the first place.
And how does TFA propose to make self-replicating robots feasible?
The first step would be to simplify the solar panels' design as much as possible. "Instead of having 1,000 different types of screws," he says, "let's have five."
Brilliant! Don't you HATE how current-generation solar panels use 1,000 different types of screws?
That that is is that that that that is not is not.
"No it isn't. There are extremely complex geological problems that have to be solved so that the radioactive isotopes don't end up in groundwater."
I'm speaking of waste annihilating molten salt reactors. It is just wrong on so many levels to bury valuable nuclear fuel when we can get energy from it.
"The reactor you speak of, IFR..."
I speak of waste annihilating molten salt reactors, liquid fluoride thorium reactors, and other liquid fuel technologies. Anything that uses liquid sodium as a coolant seems like a very bad idea to me.
"So it is extremely unlikely that these reactors will ever be built commercially."
I believe that they will be built just not in the USA, at least not at first. The US DoE is exceedingly risk adverse and therefore I suspect that they will simply not allow a truly new reactor design to the built in its jurisdiction. We will see Canada, China, UAE, or some other nation do something new first. After a few years the DoE will be dragged kicking and screaming to allow something new in the USA. It doesn't help that the existing nuclear power industry lives on the razor blade model, they will practically give away a nuclear power plant just so that they can sell solid fuel assemblies to the new owners of the power plant at, no doubt, a very high profit margin.
The only exception that I can see to this is the Department of Defense, it has it's own nuclear power program and it does not need the permission of the DoE to operate. It does have to play nice to the extent that the current rules require all fission fuel to be bought from the DoE. There's probably ways around that too.
I am armed because I am free. I am free because I am armed.
In my lecture series, I demonstrate how the Internet, affordable space access and Telepresence combine to allow solar energy farms to be built in orbit, at L points and on the moon - by people on earth remote controlling androids and robots.
It is just wrong on so many levels to bury valuable nuclear fuel when we can get energy from it.
If it is buried then it is also secure and difficult, but not impossible, to extract and use again.
I speak of waste annihilating molten salt reactors, liquid fluoride thorium reactors, and other liquid fuel technologies.
Are these on the syfy channel or do you have a link to this technology, the expected service life of a reactor and the energetic costs of demolision?
The reactor technology I speak of, has been developed, tested and proven to work, i.e. it's real. It's burnup rate makes it much more efficient as a waste anhilation reactor. Can you cite the burnup rate of what you propose?
Anything that uses liquid sodium as a coolant seems like a very bad idea to me.
Anything that creates a waste stream of Thallium-233 makes explosive radioactive sodium look like fairy floss. It's very nasty stuff.
I believe that they will be built just not in the USA, at least not at first. The US DoE is exceedingly risk adverse and therefore I suspect that they will simply not allow a truly new reactor design to the built in its jurisdiction. We will see Canada, China, UAE, or some other nation do something new first. After a few years the DoE will be dragged kicking and screaming to allow something new in the USA. It doesn't help that the existing nuclear power industry lives on the razor blade model, they will practically give away a nuclear power plant just so that they can sell solid fuel assemblies to the new owners of the power plant at, no doubt, a very high profit margin.
Won't happen. The only reactors approved under that format come from Europe. Anything else threatens established oil and coal interests who have already shut that down. So I can't see that happening as the attempt has already been made and crushed.
It does have to play nice to the extent that the current rules require all fission fuel to be bought from the DoE. There's probably ways around that too.
Well defence has much better safety protocols than private industry and if it needs to by-pass the rules that were established out of lessons learned inside the nuclear industry to prevent accidents then you are artificially creating the scenario for another nuclear accident.
My ism, it's full of beliefs.
Someone get this person a copy of Stargate-SG1 to see just how bad the idea of self replicating robots is.
The more diffuse you make it, the less-efficient the transfer
That's true for heat engines, but we're basically talking about a large microwave receiver.
the greater the requirements for the Earth-based power receiver station.
Yeah, a square mile or so of wire grid, tuned to receive a particular frequency, possibly supported by posts or on top of a building so that the space gets used efficiently.
only fried thousands of birds per year
How do you 'fry' a bird with radiation that doesn't interact with it? We would want to use a frequency that doesn't interact with water - the opposite of the way the one in your kitchen works.
The second edge is political/PR.
But that's true for anything. If people freak out, we may wait a couple of generations. This isn't the kind of thing that's going to happen (on a large scale) in the next couple of decades (if ever).