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Tapping Solar Wind's Renewable Energy
A few folks noted a story making the rounds about the huge energy potential just blowing past the planet in the form of solar wind. This research involves putting a satellite into orbit with a thousand-meter cable and a 5,000-mile sail to generate more power than the earth currently uses.
However, when you consider that the solar wind is the only thing keeping the aliens at bay, you might think twice about disrupting them.
Am I the only one slightly concerned about this idea turning the Earth into an interstellar spacecraft, solving the global warming problem permanently (as far as humans are concerned)?
You do not have a moral or legal right to do absolutely anything you want.
The first thing any government will ask is: "So who will be in control of all the world's power?"
I played that version of SimCity. The IR Laser beam always ended up incenerating my town.
If the satellite is attached to a 5000km sail, which is spread so as to catch the solar wind, what's to stop it from blowing away?
Also, who gets to volunteer to have the bazillo-watt microwave laser pointed at them? I've played sim city. I know it's only a matter of time before the satellite moves and cuts a firey swatch through my town!
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
"...blowing passed the planet..."? Damn, I mist it...
A cynic is what an idealist calls a realist...
Mr. Burns already built the sun blocker. http://www.imdb.com/video/hulu/vi1590099993/
Always go to other people's funerals, otherwise they won't come to yours.
Click me. This article is paywalled after you read a few stories, but the paywall is a javascript popup. Noscript lets you read the article.
"thousand meter cable, and 5,000 mile sail" Meters and miles. Isn't this use of mixed units the error that doomed a mars satellite?
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...what?
Then what? What happens next? Don't leave me in suspense!
If we had the energy and resources to build such a thing, we wouldn't need to. As with all Space Nuttery, this makes no sense at all. First it's space-based solar arrays with ground-based microwave antennas. When that has been shown with high-school math to be completely deluded, move on to the next unrealistic, irrational, unbuildable sci-fi fantasy!
A few folks noted a story making the rounds about the huge energy potential just blowing passed the planet in the form of solar winds.
Really? Editors don't read the first sentence of a submission?
...with all this hippie "renewable" energy crap and instead just build more nuclear power?
warning; it's goatse
Good luck with that.
If we put this 5000 mile wide "sail" up at an altitude of, oh, let's say 350 miles. Where is this 3000 foot cable attached.
Okay, one end on the sail, and the other end to something at 349.5 miles?
So I always thought fusion would be the first thing to provide an infinite resource (electricity), but it looks like this is a more viable (read: closer) solution.
If humanity gets one resource that is in essence, infinite, it would seriously change our race. I hope, for the better.
No, it doesn't work that way. Gallileo satellite system. Paid for by Europe. Had to change to accommodate US interests.
Or Else.
So, your assertion should be: like with anything else in politics: "Whoever has the biggest wish to use a gun".
OK, if we put up a rectangle 8,000 kilometers by 8,000 kilometers, it'll produce 100,000,000,000,000 times the energy we need.
WHY DON'T THEY SUGGEST A 1 KILOMETER BY 1 KILOMETER SAIL?
What's going on here? Did the guys being interviewed say something reasonable, and then also abstract it to a high number for the reporter, and the reporter only decided to write up the insane, absurd, bizarrely huge number? Or were the guys being interviewed just nuts?
Why don't they test this by powering the ISS?
The Kruger Dunning explains most post on
Er, in what way do you suppose the solar wind is "renewable"?
Burns: We're building a casino!
McAllister: Arrr. Give me 5 minutes.
According to the team's calculations, 300 meters (984 feet) of copper wire, attached to a two-meter-wide (6.6-foot-wide) receiver and a 10-meter (32.8-foot) sail, would generate enough power for 1,000 homes.
So why would we build one sail, which would be a target and fought over by countries and an untold number of businessess when you could run up a bunch of smaller sails? Easier to build and maintain, which lowers the barrier to entry and stops the wars and lawsuits which would inevitably break out over THE sail. I guess you have to dream big, but like anything, start small.
I call it 'The Aristocrats'
They're proposing we build a sail that when viewed two-dimensionally next to Earth is over half the size of the entire planet? Even if you ignore the issue of space debris punching holes in this thing left and right the logistics of creating and "stitching" this together in space are unbelievable.
...how TFA perfectly identifies the only big shortfall of this highly feasible project... ...
Either the author is totally clueless or lacks the simple imagination simple imagination to foresee all the other shortfalls of this silly idea (I wouldn't even dare to call this a 'project').
Of course, there's a lot of potential in solar win (no pun intended), but exploiting it as TFA describes it and for the use TFA proposes would fit perfectly in the children sci-fi/future books from the 70'. I can only hope they totally misunderstood and misreported the original work at WSU.
http://en.wikipedia.org/wiki/Space-based_solar_power
the power down to the Earth but being able to get a satellite into orbit where the components can handle the power coming off the line and converted to the beam. Wouldn't the conversion generate a lot of heat?
* Winners compare their achievements to their goals, losers compare theirs to that of others.
This seems like it would be more applicable to powering a future moon base and manufacturing fuel for interplanetary travel there.
Hulu == USA only!
Obama's legacy: (N)othing (S)ecure (A)nywhere and (T)error (S)imulation (A)dministration
Why not combine the concept with the space elevator concept, and just put a direct cable in between earth and space, the cable can they have a dual function. Granted you might need a really thick cable to carry so much energy, but seems like it might work.
I vote they point that honking big power laser at the moon for a couple of years so they can work out any bugs in the targeting control system.
They can always use the power to work on in-situ zone refinement of lunar material.
Or carve honking big glowing letters into the moon and sell the advertising space to fund the work.
Didn't Nasa teach us anything? 5000 mile and 1000 meter? Pick a unit and stick with it!
-Xoltri
just turn disasters off and no risk of fire at the down link site.
Dude, get your units straight? Metres and then miles? Be consistent, 5000 miles are 8000 Km! Is it that hard?
Lets play with the heat idea a bit, but from another perspective.
From TFA:
The rest of the energy would power an infrared laser beam, which would help fulfill the whole planet's energy needs day and night regardless of environmental conditions.
The main shortfall of this approach is that over the millions of miles between the satellite and Earth, even the tightest laser beam would spread out and lose a lot of its original energy.
So the tight infrared laser would diffuse in the atmosphere? infrared = heat right? and that energy lost is into the earths atmosphere, right?
Think about the french fries under the infrared heat lamp at the fast food place down the road...
A 1000 meter cable obviously means that it's only orbiting 1000 meters off the ground. That's the cable is the plug into the grid, right? Sheesh. It would have to me at least twice that to be practical. Do I have to think of everything around here.
yeah, and when are we gonna get that pellet that turns water into gasoline so I can save money on gas?
From the article:
"According to the team's calculations, 300 meters (984 feet) of copper wire, attached to a two-meter-wide (6.6-foot-wide) receiver and a 10-meter (32.8-foot) sail, would generate enough power for 1,000 homes.
A satellite with a 1,000-meter (3,280-foot) cable and a sail 8,400 kilometers (5,220 miles) across, placed at roughly the same orbit, would generate one billion billion gigawatts of power."
Okay according to google the average us home uses 920kWh/mo. (energy) or a little over a kilowatt (power). (Sounds about right, that's like running a single heavy appliance continuously 24 hours/day). So 1,000 homes is about a megawatt. But the article claims that by scaling up the sail by a factor of a about a trillion (from 10meters/side to about 10,000kilometers/side) increases the power recovered by a factor of a BILLION trillion (that's what a billion billion GIGAwatts is to a mere megawatt).
I think somewhere along the line somebody added an extra billion.
Even so, the claims are still a little hard to take, that implies a "sail" only a bit larger than ten kilometers on a side could power all of earth's homes. (Assume that there are 1 billion homes and that each uses the US amount; 10 sq. kilometers is a million times larger than 10 sq. meters). So why are they talking about a sail 8,400 kilometers sq.?
The numbers just don't add (multiply actually) up. I think that the first mistake/exaggeration comes from the claim that a 10 sq. meter sail could power 1000 homes. That's much more energy than could be gotten from a solar array; total solar power is around 1kW/sq. meter, so a 10 sq. meter solar cell at 100% efficiency would "only" generate 100kWs, enough for 100 homes not 1000). Anyway, these mistakes are annoying because this seems like it could be a promising technology if only, as a previous poster mentioned, to power our space based equipment. However, does it really seem likely that the big old fusion reactor in the sky (the sun) is putting out orders of magnitudes more energy in the form of the solar wind than it is through plain old radiation (sunlight)? Don't you think the nuclear physicists would have wondered where all the energy is going? Don't you think all the spacecraft flight planners would have wondered why their spacecraft were literally being blown off course by a force much stronger than solar radiation which they already take into account?
Anyway, maybe I've made an obvious mistake in my calculations, it's late in my part of the world and I need to sleep.
So a reasonable sized one of these could use the electrical power for an ion drive and cruise around the solar system for free, to presumably mine asteroids for more copper and to build more ships.
Solar wind doesn't act like wind on Earth, and the satellite wouldn't generate electricity like a windmill.
*facepalm*
Are people really so dumb that they need this explained to them? Am I asking an obvious question?
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
They could store the energy in really big springs and bring them back to Earth in the space shuttle.
Actually all these SPSS plans are all a big shuck. They tell the groundhogs that they're going to send back orders of magnitude more energy than civilization needs. When really, it makes more sense to use the power in situ and build space colonies to take advantage of it. It's all just a stalking horse to get the flatlanders to pay for their zero-G love hotels.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
And while we're still going to need new sources of energy even if we do all the above, someone explain to me how it's going to be more economical to harvest the solar wind in this way than it is to just use existing PV technology on earth. The solar wind project would require 1) tons of R&D to get it in shape to deploy, 2) huge expenses in lofting the collection equipment, building ground stations, etc, and 3) probably a lot of other expenses I haven't thought of.
We can do solar thermal, PV, wind, and nuclear with technology we have RIGHT NOW. We really don't need more exotic technologies to generate electricity.
Whatever technology is utilized to keep the sail from blowing away can also assist in the fight against global warming AND cut the travel time to mars as low as we want!
Controlling population growth is less realistic than the freaking space elevator? I've got some news for you: lots of countries on earth are declining in population right now: Japan, Russia, lots of Europe. China has cut population growth enormously. The US is essentially only growing through immigration.
Lowering the earth's population is totally doable. Space elevator? Call me when we can practically make carbon nanotubes longer than a millimeter. Then we can think about a space elevator. In the meantime, continuing to get our reproductive rate under control is something we're absolutely going to have to do.
how do you successfully attack someone who controls a 30 million billion jiggiewatt deathray?
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Dammit, what is wrong with these reporters? Do they really feel they need to so grossly oversimplify and misstate what's really going on? Do they really have such a low opinion of the intelligence of their readers? Or are they themselves really that idiotic? Harvesting the solar wind has nothing to do with solar power in the conventional sense, nor does it have anything to do with wind power. About the only connections I can see is that a) the Sun is the ultimate driver in all cases and b) the words "solar" and "wind" show up in both places.
And there's not the slightest chance you're going to get this thing built and producing power for less than what we can currently produce power for. Which is why no one is seriously pursuing electricity generation in space.
For this to be even remotely feasible, you'd have to be able to produce (renewable) electricity cheaper than we can already do it on earth. And there's just no way you're going to be able to loft a big energy collector into space and then beam the energy back to earth for less money than you can just build regular old ground-based solar PV or wind or whatever.
TheMidget has a history of goatse posting. Skip his posts.
thousand-meter - 1 km
meters & miles - stick to one?
from TFA
they made "practically no allowance for engineering difficulties," and that these problems would have to be solved before any satellite like it could be deployed.
Yes, those pesky 'engineering difficulties' are always holding back the great thinkers of the day...'oh, wait, you actually want to build that space elevator thingie? Well, find me a material that's about 10 times stronger than carbon nanotubes, at least half the weight, impervious to all weather, impact damage and other wear and tear, and economic enough to produce the 36,000 km needed, then we'll talk!'
Engineers. Such buzzkills, the lot of them.
Seriously, though, just because we can imagine it, doesn't necessarily mean it's going to happen, at least not in our lifetimes. Science and engineering are moving forward at an incredible clip, but some things will be 'just out of reach' for quite a while yet.
That being said...the potential for using this solar sail as propulsion for extra-orbital vehicles is definitely much more feasible. Now that is exciting news!
"I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
So, I think this idea needs to be filed under, "theoretically interesting but not practical." Don't get me wrong, this is an intriguing, albeit complicated, design that may have potential in the future. But currently, there are a lot of engineering parameters that are going to shoot a satellite like this into the impractical/impossible area. First off, if you are pumping that many electrons (even for the small solar sail design discussed) repeatedly through copper wires, you have a good chance of melting your wires. This design has the satellite strung out in a long, awkward shape. Piping excess heat out of those cables and into an appropriately large radiator is going to be a pain in the ass, if not downright impossible.
Secondly, this satellite is a control engineer's worst nightmare. It looks like this satellite consists of multiple moment arms strung together that will continuously have a torque impressed upon them (solar wind, magentic forces, etc.). Trying to damp the sheer rotational momentum of this satellite, much less the perturbations induced by an inconsistent solar wind load, is going to saturate any reaction wheels or CMG's you put on the system. If you are going to use thrusters for momentum dumping, then you are going to need an epic crapton of fuel just to keep this satellite pointed and stable. It wouldn't be an easy problem, even for the smaller designs.
Thirdly, not only will maintaining the appropriate attitude for the collector be a difficult task, but the pointing requirements for that deathray, I mean laser, are going to be constrictive. Any controls engineer would be hard pressed to get that thing pointing within the 0.001 degrees (approximate guess) necessary to keep from melting someone on the ground. Add to that problem the consistent oscillations induced on the semi-rigid spacecraft body by a varying solar wind and you have a non-trivial pointing problem.
On top of that, communicating with such a satellite will be a colossal pain in the ass. Whatever communication dishes you have mounted to this thing are going to be subject to a lot of noise based on the magnetic field produced by the satellite as well as the high-radiation environment the satellite is living in. Communicating through all that noise is going to require quite a bit of power, and/or some very large dishes. Again, this isn't an impossible design challenge to overcome, but couple it with the cost of troubleshooting the other issues I listed above and you have a very nontrivial engineering task.
So sure, from a scientific theory point of view, this design is interesting (and I am still going over the details). From an engineering point of view, however, this satellite is a God-forsaken nightmare to design. It would be an extraordinarily expensive piece of equipment. There is a good chance that the first one or two would be lost early in the mission cycle. This is a project that would require an enormous amount of funding and political will to get pushed through. I'd be less surprised to see a PV based power generating satellite get produced in the next decade than seeing this design go anywhere past paper.
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TFA reads like it was written by a crackhead in need of a fix.
1) Only one dimension is given for the sail, its "width." Should we assume it has a square profile, or is its length greater/less than the width, or is it even rectangular? Who the hell knows.
2) No direct mention is made regarding where this "satellite" is located. The cryptic comment "over the millions of miles between the satellite and Earth" doesn't help much. Certainly too far to be geosynchronous. Perhaps a heliosynchronous orbit? Who knows.
I picked a bad day to let my subscription to the International Journal of Astrobiology lapse.
hi!
It's only like two pages and not very technical. The main gist of it is that the author isn't proposing this as a project for supplying energy to Earth. He is proposing that this is something someone else might plausibly build that we can look for in SETI. (Although I think he misses a trick here in that this is obviously how the Motie power the solar-sail spacecraft that are headed our way).
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
My question exactly. Or almost exactly -- from the number of zeroes you're using the European "billion" (million million) rather than the North American (thousand million).
But even assuming the latter, a 1 km square sail gives roughly 6 times the energy Earth uses currently (by their figures). And a 1 km square sail is a heck of a lot easier to build than an 8000 km square one.
That number, though, surprises me. Sunlight flux is less than 1.5 kW/square meter at Earth's distance. Call it 2 GW per square kilometer -- nowhere near Earth's energy use (in the 10-20 TW range)*. This is talking about tapping solar wind rather than sunlight, but I find it hard to believe that solar wind flux is that many orders of magnitude more energy intensive than sunlight. If it is -- and despite Earth's magnetic field -- global temperatures are going to be driven mostly by solar wind effects. The numbers in TFA must be wrong, i.e. typical popular science reportage.
(* TFA says an 8,400 km square sail will produce "a billion billion gigawatts", which works out to over 14 terawatts per square kilometer. The numbers are totally fucked up. Somewhere in there I think somebody confused meters with kilometers and/or watts with kilowatts.)
-- Alastair
I still think we just don't know enough about weather to look at wind as a renewable energy source.
*DrugCheese rants*
I think they got the measurements and units wrong. The article says that the power would not be generated like a windmill but from a wire. Then it says that the wire would be relatively short and the sail impossibly huge. Chances are the article got it wrong and the reality is that a small sail would be used to tow out a long 5,000 mile spool of wire. As the solarwind particles cross over the wire it will create the electricity just like passing a wire through a magnetic field creates electricity. I would like to read the original source rather than this typical example of science journalism.
Test the theory out on the space station. They have had a fair share of issues with their solar panels, maybe this alternate power supply could create enough energy to not only run the space station but some ion rockets to keep it in the proper orbit.
"Be kind, for everyone you meet is facing a great battle." - Philo of Alexandria -
The earth is heating up because more energy is being released into the biosphere than is being radiated out into space.
And now we're looking at ways to bring more energy than the earth has received in the past into the biosphere and release it.
Until we find a way to add more fuel to the sun, the solar wind isn't renewable energy. Plus, it's nuclear man. Nuclear!
that is all
How is that for hypergeeky speculative technology solution that saves the day?
Should be able to have a solar wind collector on the surface of the moon, instead of in orbit. Use the solar wind collector to mine Helium-3 on the moon, and send it back to earth for IEC fusion reactors.
See article touching on Helium-3 and IEC fusion reactors.
http://www.technologyreview.com/Energy/19296/
There is a spiffy ppt presentation spelling all this out.
http://web.mit.edu/22.012/www/presentations/Helium-3%20version%202.ppt
I guess it will get build when the world stops laughing. We can get it in orbit cheaply with our space elevator.
Winkey shortcut mapping for 64bit windows. WinKeyPlus
lol Millions of miles away?. Where did they plan on putting it in orbit, Near Uranus?
Their figure of 1 billion billion gigawatts of power is more than the entire Sun produces, and only about a millionth of the power produced by the Sun goes into the energy of the solar wind. Severe misuse of illegal drugs is about the kindest explanation.
OK, so shooting power in from space is a recurring theme in the quest for reliable baseload power. For me the dreamer aspect of this has always been launch costs, which the more serious slashdotters here have demonstrated just...don't...add...up. However, does the 'Hydrogen gun' make Space PV power, or even this solar wind power concept, economical? What do you all make of the Hydrogen gun? Indeed, does it warrant its own slashdot thread? (I've never known how to generate a thread here).
Personally with peak oil & global warming bearing down on us, I'm hoping we get serious about Gen3 and Gen4 nuclear power. (Gen4 promises to run the world for 500 years just on the nuclear 'waste' we have already produced). But I'd love to see the more technical slashdotters amongst us analysing conventional solar PV power beaming stations with the Hydrogen Gun economic models.
Aparently it's about this article: http://www.lpi.usra.edu/meetings/abscicon2010/pdf/5469.pdf
1) Producing the desired magnetic field with the proposed wire-loop can't work, you can probably get a few gigawatt from Maxwell rotating in his grave in result of that paper.
2) The electric current in the wireloop is aparently driven by a static electric field, ever hear about static electric fields being conservative?
3) Somehow electric current is generated by catching electrons, but where do they leave the System?
4) Where does the energy come from to separate electrons and protons from the plasma? To put some spatial distance between positive and negative charge you need energy.
5) A sail of 8.400 km with (square or what?) shall produce 10^27 W of energy. That means over a 4-Billionth (1/4*10^9) of the solid angle of the sun it produces 2.5 times the total energy output of the sun. Surrounding the sun completely with these contraptions should yield 10^10 times the total energy production of the sun.
This paper can't even stand up to basic highschool-physics.
"By the way if anyone here is in advertising or marketing... kill yourself." -- Bill Hicks
Considering the many errors and misunderstandings that Slashdotters are making and propagating in this discussion, I'd say yes.
Some people seem to think it's solar power. A lot of people seem to think that 1km cable is to transport power to earth, and a surprising number of people fail to grasp that 100 billion is really quite a lot.
Not to mention that they blame NASA for the summary.
Kites fly away in the direction of the wind. What happen when that point rotate in the direction of the sun? Does it come fluttering down into the atmosphere? Perhaps it just winds the cable around the planet.
That could create a truley global yo-yo for the alien children to play with.
Slowly waving my hand - "This is not the sig you are looking for."
Interesting that you seem to have gone from making normal posts to goatse-ing with url shorteners. That's a pretty amateur method anyways, it only catches n00bs.
"When information is power, privacy is freedom" - Jah-Wren Ryel