Satellite proposed to send solar power to Earth

Apr 11, 2012 by Bob Yirka report
Image credit: John Mankins

(Phys.org) -- Artemis Innovation Management Solutions has been given some seed money by NASA to look deeper into a project the company first proposed last summer; namely, building a satellite that could collect energy from the sun and beam it back down to Earth to add to the electrical grid. Building such a satellite has been bantered about for several decades by various groups and scientists, but until now, no one had come up with a design that would work given all the constraints of the time. But now, an idea proposed by longtime NASA engineer John Mankins, now with Artemis, has clearly created enough interest within NASA that some money to investigate the idea is being offered.

Mankins idea is a bio-mimetic approach, meaning it’s based on the way something in nature goes about handling a similar situation. In this case, it appears that something is the common flower, which uses its petals to collect solar energy. Mankins idea is to build petals out of an array of many small mirrors that would direct sunlight to . The energy created by the solar cells would then be converted to microwaves which would be broadcast or beamed back to a receiving station on Earth, where electricity (perhaps as much as tens of thousands of megawatts) would be generated from the energy in the microwaves. To make the project feasible, the mirrors and solar cells would be small and lightweight so that they could be easily transported into space using conventional transport vehicles. And because it would be component based, construction costs would be much lower than other proposed ideas.

The project called Solar Power via Arbitrarily Large PHased Array (SPS-ALPHA) would make use of thin filmed mirrors to reduce weight which would be curved to take maximum advantage of the sunlight it receives. Also, the satellite would sit far enough away from planet Earth so that it would never be in the dark, allowing for a constant stream of microwaves.

The initial seed money is to carry out a feasibility and proof of concept study. If likes what it sees, the next step would likely be the construction of a pared down, cheaper version of the project working from a near Earth orbit. If that works out as planned, than the full scale satellite would be built and sent up, perhaps becoming the game changing solution to energy production that so many researchers the world over have been looking for.

Explore further: Scientists find meteoritic evidence of Mars water reservoir

More information: www.nasa.gov/offices/oct/early… nkins_sps_alpha.html

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User comments : 75

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Lurker2358
2.3 / 5 (19) Apr 11, 2012
Gave it a 5 for the heck of it.

Don't want to think about what this will do to birds and insects, or humans in the area of the ground-based receiver.

You know, being microwaved by a couple gigawatts of energy would probably look about like a scene from the movie "The Core" (bad science in the movie.)

Who would want to live anywhere near the ground-based receiver?

Some kind of alignment error or some crap like that, and you'd literally fry people or livestock or crops easily...
tadchem
4.1 / 5 (9) Apr 11, 2012
"the satellite would sit far enough away from planet Earth so that it would never be in the dark, allowing for a constant stream of microwaves."
There are only a few earth orbits that can accommodate this requirement. LaGrange points are quite far from earth, complicating the quantitative microwave beam transmission problem. Horseshoe orbits and co-orbits have variable distances from earth. Tadpole orbits have complex libration motions to account for, which would require constant re-aiming of he microwave beam.
They will just have to accept the occasional eclipse 2-3 times a year.
Lurker2358
2 / 5 (20) Apr 11, 2012
This is actually extremely stupid and inefficient UNTIL you exhaust space for ground-based solar collectors.

However, using it as an off-board engine (fuel source) for an ion propulsion system on a spacecraft, i.e. and electric solar sail with entirely off-board power would be incredibly light and efficient...

For powering a lunar colony on the "far side of the Moon" might not be a bad idea, since you don't have collateral damage issues nor atmosphere to screw up the beaming, and the far side of the Moon is where you'd want to be for any potential Lunar telescope mission to get away from Earth radio noise and other stuff.
Uzza
4.2 / 5 (11) Apr 11, 2012
Space based solar just isn't worth it in terms of cost over ground based alternatives.
Even with launch costs reduced to 1%, it's still cheaper to build solar installations on the ground and add storage to it.

Do the math:
http://physics.uc...r-power/
Lurker2358
2.1 / 5 (11) Apr 11, 2012
The energy created by the solar cells would then be converted to microwaves which would be broadcast or beamed back to a receiving station on Earth, where electricity (perhaps as much as tens of thousands of megawatts) would be generated from the energy in the microwaves.


I wonder what the specifications and costs will be for a 10 gigawatt microwave receiver to convert it back to grid electricity?

I mean, it would have to be an antenna that converts it directly to electricity to be efficient. The antenna would need to be at least 80 to 90% efficient to be cost-effective.

Boiling water in a catch basin to turn a turbine would be horribly inefficient as a whole system.

Even with the antenna, you'll have a gigawatt worth of waste heat, so maybe you end up boiling water anyway.

The maintenance costs of this will be unimaginable, and atmospheric scattering will cause any surrounding vegetation or animal or insect life to be continually bombarded by lethal beams.
Lurker2358
1.9 / 5 (13) Apr 11, 2012
Just to give an idea, if the ground-based antenna was a square kilometer, 10 gigawatts (tens of thousands of megawatts) would still equal 10,000 watts per square meter on the surface.

Which begs the question of how they intend to harvest that much energy in the first place, because you'd need about 10 square kilometers (1km by 10km) of arrays in space.

At any rate, 10,000 watts per square meter.

If a human accidentally got exposed to some scattering or reflected radiation from that for even a second or two it would severely burn their flesh, eyes, and even internal organs.

think about it. A sunburn is 1000 watts, and a lot of that is reflected by your skin tone and such, and 1000 watts is a lot less and air-cooled much faster.

Microwaves penetrate and are absorbed by water molecules.
RoBernal
1.6 / 5 (13) Apr 11, 2012
This system to redirect energy to the planet would contribute to the global warming. The big amount of energy entering all the time increase the UV rays that can not get out of the atmosphere because of the greenhouse effect.

In the other hand, we have the risk that it system represents to the life and to the planet in self, because it is like a big magnifying glass ready to burn all things, starting forest fires, fires into the buildings... or worse yet, this technology can be used like a weapon.
Telekinetic
1 / 5 (3) Apr 11, 2012
Let's give long overdue credit where credit is due-

http://www.tfcboo...0-00.htm
baudrunner
1 / 5 (3) Apr 11, 2012
I think that the project proposal could be advanced more readily by using lunar ground-based solar power collectors that beam energy to autonomous working machinery on the moon. For applications that require regolith-gathering machinery, for example, the roving vehicles would not be encumbered by ungainly solar cells straddling their backsides. That would be the ideal application.

Then again, why not just use that lunar solar power plant for recharging purposes?
dnatwork
3 / 5 (6) Apr 11, 2012
Why beam it? Build a space elevator, too, and use those cables to conduct the electricity to the ground.
LariAnn
2.3 / 5 (6) Apr 11, 2012
Even if this system were made efficient and workable, it still results in a centrally controlled energy production system, which IMHO is not really where we want to go (we are already there). A mega power source controlled by government(s) or corporation(s) is part of the problem (think oil cartels). What we need is a decentralized energy delivery that enables small communities or even individuals to be energy self-sufficient and not dependent on the whims of either governments or corporate interests.
sstritt
2.3 / 5 (9) Apr 11, 2012
Which picture accurately depicts this device? I don't understand how the flower shaped one would work.
Infinion
2.5 / 5 (8) Apr 11, 2012
I would honestly prefer energy transmission through laser light to a receiver. Just have several different receiving points on the planet when it is cloudy and divert power to the most favorable location.

Also, like Lurker2358 said, the use of solar arrays in space as a remote power source for ion-propulsion satellites would allow design of such crafts to be lighter, faster, and more accommodating of additional equipment
Infinion
1.7 / 5 (6) Apr 11, 2012
I wonder what the theoretical limits are for concentrating light onto a solar panel before losses due to entropy (waste heat) and black-body radiation limit any further energy capture

Also if a situation like this did take place, I wonder if our space corporations would use Stirling engines to recover that waste heat into usable energy
sender
1 / 5 (1) Apr 11, 2012
Aerosolized surface insulator materials and reflectance films would allow compression of building materials and lessen construction time if assembled in orbit under microgravity.

Additionally if these polymers contained CQD layers which assemble in presence of optical radiation pressure the proximity of the satellite array to the solar radiosphere can be shortened.
baudrunner
2 / 5 (4) Apr 11, 2012
Additionally if these polymers contained CQD layers which assemble in presence of optical radiation pressure the proximity of the satellite array to the solar radiosphere can be shortened.
Okay.. that's just talking way-ay too much. You should have just stuck with the first paragraph, which is also pretty much off the wall
dschlink
3 / 5 (2) Apr 11, 2012
To answer a few questions:

Both pictures are possible configurations.
Concentrations of up to 10^^4 suns have been used.
The down side of trying to use this power for ion spaceships is maintaining beam focus over large distances.
TheGhostofOtto1923
3.1 / 5 (15) Apr 11, 2012
Who would want to live anywhere near the ground-based receiver?

Some kind of alignment error or some crap like that, and you'd literally fry people or livestock or crops easily...
Perhaps you might want to do a little research to see how scientists have already addressed these obvious issues? Or are you back into that manic phase of yours where every notion that pops into your head seems like an exclusive revelation and a gift to all mankind?
If a human accidentally got exposed to some scattering or reflected radiation from that for even a second or two it would severely burn their flesh, eyes, and even internal organs.
Well I am sure nobodys ever thought about that. It sounds like what might happen if one should stumble into a large electrical buss? This is why they put fences around transformer yards. I am confident similar safeguards will be provided for these things. Dont you think? QC?
TheGhostofOtto1923
2.8 / 5 (9) Apr 11, 2012
I would honestly prefer energy transmission through laser light to a receiver. Just have several different receiving points on the planet when it is cloudy and divert power to the most favorable location.

Also, like Lurker2358 said, the use of solar arrays in space as a remote power source for ion-propulsion satellites would allow design of such crafts to be lighter, faster, and more accommodating of additional equipment
and lurker/QC knows this is also not an original idea. A little research and a link would have been more helpful.
http://en.wikiped...opulsion
http://en.wikiped...opulsion
KhanneaSuntzu
3 / 5 (2) Apr 11, 2012
Well this not really a NEW thing...
* http://www.scoop....rsus-oil
* https://www.faceb...edsolar/

Actually... this is about time.
Parsec
5 / 5 (6) Apr 11, 2012
"the satellite would sit far enough away from planet Earth so that it would never be in the dark, allowing for a constant stream of microwaves."
There are only a few earth orbits that can accommodate this requirement. LaGrange points are quite far from earth, complicating the quantitative microwave beam transmission problem. Horseshoe orbits and co-orbits have variable distances from earth. Tadpole orbits have complex libration motions to account for, which would require constant re-aiming of he microwave beam.
They will just have to accept the occasional eclipse 2-3 times a year.

polar geosynchronous orbits would work well. In fact, any geo-synchronous orbit above or below the earth's shadow would work.
Parsec
5 / 5 (6) Apr 11, 2012
Space based solar just isn't worth it in terms of cost over ground based alternatives.
Even with launch costs reduced to 1%, it's still cheaper to build solar installations on the ground and add storage to it.

Do the math:
http://physics.uc...r-power/

Not necessarily. Solar intensity is much greater in space, and its generating power 24 hrs/day.
kaasinees
1.8 / 5 (11) Apr 11, 2012
Anyone else scared that it will be used as a weapon?
TheGhostofOtto1923
2.3 / 5 (6) Apr 11, 2012
Space based solar just isn't worth it in terms of cost over ground based alternatives.
Even with launch costs reduced to 1%, it's still cheaper to build solar installations on the ground and add storage to it.

Do the math:
http://physics.uc...r-power/
Yah this is last weeks mindset. Scientists and engineers keep on improving the cost/performance ratio, per the article. Stay tuned.
frukc
3 / 5 (4) Apr 11, 2012
Anyone else scared that it will be used as a weapon?

yup! tune it to 2.4GHz and boil whole cities. :))
Infinion
1.7 / 5 (6) Apr 11, 2012
and lurker/QC knows this is also not an original idea. A little research and a link would have been more helpful.
http://en.wikiped...opulsion


right, and so i guess what I'm asking is why did they choose microwave transmission over laser transmission? Is it because microwaves can penetrate the upper atmosphere more easily in its wave form than any spectrum of laser light? Or because there isn't a receiver for lasers that attains as high of an efficiency as a rectenna?

MorituriMax
2.8 / 5 (5) Apr 11, 2012
Anyone else scared that it will be used as a weapon?

We already have nukes, if someone is bound and determined to kill lots of people.
TheGhostofOtto1923
2.1 / 5 (7) Apr 11, 2012
Anyone else scared that it will be used as a weapon?

We already have nukes, if someone is bound and determined to kill lots of people.
We have LOTS of much more effective weapons because they are specifically designed AS weapons. These stations would be sitting ducks. Many Players already have weapons capable of destroying them as well as any nation which would attempt to use them inappropriately.
antialias_physorg
4.3 / 5 (6) Apr 11, 2012
Not necessarily. Solar intensity is much greater in space, and its generating power 24 hrs/day.

It's not much greater (1300W/square meter as opposed to 800-1000 W/square meter at ground level). And much of that extra power is not in a usable energy range for PV cells.

The total gain due to more daylight hours and higher solar constant is about 3:1 when compared to a ground based installation. Now picture the size of even a modest solar powerplant. You could build 50 of those on earth for the cost it would take to get one of those into orbit.

If you do the math then the fuel you burn to get such stuff into orbit produces more power than you will ever get back - even if it stays up there for 50 years.
Better just burn that fuel down here (under controlled conditions). That's MUCH more environmentally friendly.
antonima
1 / 5 (3) Apr 11, 2012
I would be worried about this being used as a weapon. The way it is set up it would be ready to do damage at a moment's notice to anything on it's side of the earth, and also to satellites.

Aside from this I don't see how the design works. Sure, we can focus sunlight onto a single point. Thats how many solar plants work already. How does it change anything by being in space? There is in fact even less ways to dissipate the heat since there is no conduction out there.
StarGazer2011
1.6 / 5 (7) Apr 11, 2012
Its just a stupid idea and will never happen. All further discussion and funding is a waste of vital resources on adolescent sci-fi masturbation.

Its stupid because of the maintenance cost, the danger of accidentally frying kilometers of land if the thing goes out of alignment, the maintenance cost, the ease of weaponisation (with no pesky fallout to worry about, far more likely to be actually used) and the undoubted environmental disruption of pumping GW of energy into the atmosphere (it would kill more birds than wind turbines) and its effects of H20 in the atmosphere (boiling clouds, sounds fun) ... oh and did I mention the maintenance cost?
StarGazer2011
1.6 / 5 (7) Apr 11, 2012
Wow, can you imagine the convective currents this thing would create? Would it create tornados? According to Climate Post-normalists even 0.7C of warming can increase 'extereme weather', so what would gigawatts in a small area do?
Burnerjack
3.7 / 5 (3) Apr 11, 2012
Wouldn't it be more practical and "down to Earth" (sorry...) to go with geothermal? Is it because the lure of "research funding"(wink, wink) is too strong? This idea, when looked at with a sober eye is just ridiculous! We can drill 8km for oil, repeatedly, but 6km for inexaustable CLEAN BASELINE power with proven off the shelf technology is a no-go? Really?! Why?, somebody PLEASE explain this. I suspect the entire Hawaiian Chain could be powered by a handfull of shallow geothermal installations. And no, you don't have to tap into magma or even close. But, I guess with this so blandly off the shelf, there just isn't enough opportunity for graft. Better to send miners to Io and Europa. Oh, did I say graft? I meant research funding.
Caliban
3 / 5 (2) Apr 11, 2012

Anyone else scared that it will be used as a weapon?

yup! tune it to 2.4GHz and boil whole cities. :))


Great. Did it occur to you both that the device itself can be engineered and constructed specifically to be physically able to beam only non-lethal microwave/laser frquencies?

On the other hand, hats off for developing the idea for the next Austin Powers film.

Caliban
4 / 5 (3) Apr 11, 2012
Wouldn't it be more practical and "down to Earth" (sorry...) to go with geothermal? [...] But, I guess with this so blandly off the shelf, there just isn't enough opportunity for graft. Better to send miners to Io and Europa. Oh, did I say graft? I meant research funding.


@Burner,

I'm with you on the sad state of affairs attending the development of geothermal.

However, I would place the blame for this deplorable state of affairs not upon the mad grab for "Research Funding"
--though there ARE those who persist in milking the grant system(although government contractors are a vastly larger culprit competing for that "honor").

I would think that the listless response from the energy industry to all of the plainly apparent benefits of geothermal is that it has one glaringly obvious "downside": it would be so inexpensive to develop and maintain that it would be nearly impossible to justify continual, serial price hikes to jack up profitability.

MrGrynch
2.5 / 5 (8) Apr 11, 2012
For those of you who might worry about high-powered microwaves, the microwave oven effect only exists if resonance is achieved. This requires a confined space with specific properties, which would not exist in the open air. Yes, these would be high-powered beams, it would not necessarily damage wildlife or humanity in its path.
bardgd
3 / 5 (2) Apr 11, 2012
I go into the kitchen and put a cup of water into the microwave and it heats the water to boiling hot. What is going to happen to the atmosphere with the a continuous stream of microwaves, especially if clouds start hitting it. I think we will have a major jump in global warming. Now then build a tower that is about 5 miles high and it receives the beam.
PaulRadcliff
3 / 5 (2) Apr 11, 2012
This is a bad idea, with the micro waves, I must agree. I think launch facilities could be better used for exploration launches or asteroid mining, down the road, of course. There is plenty of space on earth and on roof tops for solar panels aplenty, and they keep promising more efficient solar cells. If I could afford all the equipment and raw material, I'd love to get off the power grid. Blood suckers. I hate Co ops. I'd love four or five wind mills generating power for me, as well.
Lurker2358
1.5 / 5 (8) Apr 11, 2012
Its just a stupid idea and will never happen. All further discussion and funding is a waste of vital resources on adolescent sci-fi masturbation.


It's not stupid in theory. Its stupid in concept and execution.

It's just the governments simply do not get the concept of how to do space-based power or colonization in a cost effective manner.

this stuff simply is not worth it when building from Earth-based resources and construction technology.

In order to make these sorts of systems cost-effective and practical, you need fully automated mining, refining, and production facilities in space (and possibly nano-assembly) on meteors and small moons, making 100% of the components from resources mined in space, that way you never pay the obscene launch costs from Earth gravity.

They just don't get that.

The Lunar solar colony issue addresses this as well.

You absolutely must have 100% self-replicating and self-maintained harvesting and production robots to make it work.
Lurker2358
1 / 5 (6) Apr 11, 2012
And to be honest, you can probably count on both hands and both feet the number of people in the world who are honest to God working on this type of robotics and self-replication at EITHER the macro or nano-scale.

Maybe Ralph Merkle and his group.

A European team.
Darpa
A Japanese team.
Maybe IBM or a few others in the U.S.

Besides those guys, most of the crap you see everyone else doing in "nano-tech" and self-assembly amounts to just toys.

Without the kind of stuff Ralph Merkle is talking about, you will NEVER be able to build this sort of system and get it into space for a profitable cost.
Burnerjack
1 / 5 (1) Apr 11, 2012
@Caliban : a first I thought your ideas as to why geothermal isn't as exploited as it could be as sound. Then it occurred to me that the product is sold at market price, therefore, generating through cheaper means increases the margin, vis-a-vis, the motive. At least until the cheaper meathod becomes dominant, then, in a true capitalist arena, competition drives the margin back down, modified by supply/demand curves. Am I wrong on this?
Deathclock
1.8 / 5 (5) Apr 11, 2012
So many stupid people comment on this website... Thank you MrGrynch for correcting them and their fear mongering nonsense.
kaasinees
1.5 / 5 (8) Apr 11, 2012
It's not much greater (1300W/square meter as opposed to 800-1000 W/square meter at ground level).

That is a lot, especially when you have it on top of your head 24/7.
And much of that extra power is not in a usable energy range for PV cells.

It is usable as a weapon, or increasing heat where it is cold.
aimbotfriend
2 / 5 (4) Apr 11, 2012
LOL, who wants to have an eye sore in the sky. You want power, build more nuke plants until fission is perfected.
Deathclock
2.8 / 5 (9) Apr 12, 2012
Eyesore in the sky?

Those are some amazing eyes you must have to be able to see a fucking satellite in orbit you retard...
mcausal
1 / 5 (1) Apr 12, 2012

It is usable as a weapon, or increasing heat where it is cold.


it could be used to unfreeze some brains ..
eachus
4.4 / 5 (7) Apr 12, 2012
A lot of nonsense being posted here. Microwave power transmission from Earth to Space or Space to Earth was proven effective a long time ago, and the numbers involved reduce the risk greatly.

First, the receiving rectenna operates at a low power density which is safe for humans, airplanes, birds, bats, and insects. Yes, this makes the rectenna large, but the 10 mile or greater diameter is possible because the elements in any area are just a few wires per square meter. Supports are needed but they can also be not very dense. The rectennas could be strung above rivers, parks, highways and even houses.

As for the risk of a wild beam or someone misusing the beam, on the transmitting side there is a small starter beam which is reflected by the rectenna. This allows the transmission antennas to be brought into phase--but only if the beam is targeted at a rectenna.

Someone could potentially sabotage the system by stealing the power, but that is the biggest risk, and easy to correct.
antialias_physorg
4.3 / 5 (6) Apr 12, 2012
Wouldn't it be more practical and "down to Earth" (sorry...) to go with geothermal?

While geothermal does seems enticing there are problems associated with it. Basically what youre doing is pumping water down and getting steam back up. So far so good. But pumping water down makes for a very slippery surface. The Basel geothermal powerplant was shut down after several earthquakes rocked the area (on a related note: In areas where large scale hydrofracking is under way the number of earthquakes has increased).
We need to figure out a way to do this better (e.g. by using areas where the thermal energy comes to the surface naturally - like in hydrothermal vents)

but the 10 mile or greater diameter is possible because the elements in any area are just a few wires per square meter.

If you have a 10 mile diameter area build a solar power plant on it. That's MUCH more effective (and way cheaper) than this scheme.
rjsc2000
1 / 5 (1) Apr 12, 2012
So, is it possible to collect power from a solar array and transmit it with microwaves to earth? Has anyone done that? I thought it wasn't possible yet...

Argiod
1 / 5 (7) Apr 12, 2012
Just what we need: a solar oven hanging over our heads. And what do we do about nations who want to cause us grief by claiming we're cooking their people/facilities/cities? I, for one, do not want to be in the neighborhood when one of these sattellites goes off-orbit and starts cooking everything/everybody in its path. And don't tell me how 'safe' it will be; I'm still getting over the recent demonstration of how 'safe' nuclear energy is (Fukushima).
Infinion
Apr 12, 2012
This comment has been removed by a moderator.
DaFranker
1 / 5 (3) Apr 12, 2012
So, is it possible to collect power from a solar array and transmit it with microwaves to earth? Has anyone done that? I thought it wasn't possible yet...

There is never such a thing as "not possible yet". Possibility is absolute, regardless of available technical means. What you mean is that it wasnt "feasible" yet.

The problem is, that's what we don't know. That's why they're paying a bunch of scientists to figure out whether it's feasible, or whether it would just be a huge waste of massive amounts of money for no results at all. That is what this article says, in a nutshell.
RealScience
not rated yet Apr 12, 2012
I wonder what the theoretical limits are for concentrating light onto a solar panel before losses due to entropy (waste heat) and black-body radiation limit any further energy capture


On earth we are just over 100 solar diameters away from the sun, so reflective imaging optics that concentrate in one dimension (parabolic troughs), could theoretically reach 100x (with ~70x-80x being practical). Systems that concentrate in two dimensions can reach 10,000x concentration.

Non-imaging optics can reach double that concentration in each dimension.

If refractive optics are used (lenses in contact with the absorber), the maximum in each dimension is multiplied by the index of refraction of the material (e.g., ~1.5 for glass).
Sigmond77
1 / 5 (2) Apr 13, 2012
ARE YOU FRICK.........EN CRAZY

the sun is ALLREADY shining it's rays on the earth. as it should

Ever play with a magnifying glass as kid.

THIS IS NUTS.
antialias_physorg
not rated yet Apr 13, 2012
I wonder what the theoretical limits are for concentrating light onto a solar pane

Melting point?
But seriously: Degradation will set in much earlier when you concentrate sunlight on PV panels. And you need to cool your cell anyhow (which is very hard to do in space, since you cannot cool anything via convection).

so i guess what I'm asking is why did they choose microwave transmission over laser transmission?

Because creating laserlight is an extremly inefficient process. Microwaves are well chosen because they can be generated efficiently and don't get absorbed as much
Burnerjack
1 / 5 (1) Apr 13, 2012
What about a coaxial geothermal system where the outer pipe is the steam pipe and the inner pipe is the water supply? At the bottom lies the turbine, maybe a helical type(?). Point being, it IS possible to achieve geothermal of infinite duration is planted deep enough. Maybe put the drill bit at the head of the assembly so it's a one step process. Lots of "maybe"s I admit. My point is: this satellite idea is moving AWAY from the K.I.S.S. principle, which many will know as "Keep It Simple, Stupid!". The power required is already here on Earth. No need to go elsewhere.
Is my geothermal idea the answer? Probably not, but if I can get someone out there thinking in a more practical direction, my work here is done.
ViperSRT3g
3.7 / 5 (3) Apr 14, 2012
"the satellite would sit far enough away from planet Earth so that it would never be in the dark, allowing for a constant stream of microwaves."
There are only a few earth orbits that can accommodate this requirement. LaGrange points are quite far from earth, complicating the quantitative microwave beam transmission problem. Horseshoe orbits and co-orbits have variable distances from earth. Tadpole orbits have complex libration motions to account for, which would require constant re-aiming of he microwave beam.
They will just have to accept the occasional eclipse 2-3 times a year.


If the satellite's orbit were at an angle to the ecliptic, it would never enter Earth's shadow, while remaining in an Earthbound orbit. There is no need for placing anything so far away at Lagrange points.
Andrew_Miller
1 / 5 (1) Apr 15, 2012
Sounds more like a space weapon....sold to the public as an energy source.
yaswanthrage
1 / 5 (1) Apr 15, 2012
why are they using microwaves?in which orbit will it be supposed to launch.how much energy will be lost while transmission to earth receiving station.which materials will be used.can we use a micro wave laser?please replay to my questions
Don Crusty
1 / 5 (1) Apr 15, 2012
Honestly, what beam could keep it's frequency from waivering across such a distance. Dissipating energy into the (upper) atmosphere could be bad enough allready. Dissipating massive amounts of energy ..... could that not prove plain catastrophic ? Also referencing old suspicions (secretivish) systems like h.a.a.r.p are actually messing with the weather in yet unknown ways.
Burnerjack
1 / 5 (1) Apr 15, 2012
@ Don Crusty: Barring Red Shift or Blue Shift, I've never heard of a "wavering frequency" with an EM radiation beam. Please elaborate.
Burnerjack
1 / 5 (1) Apr 15, 2012
It may be advantageous for both the scientific community and those resposible for funding to keep "Occam's Razor" in mind. Sheesh!...
Bob_Wallace
2.3 / 5 (3) Apr 15, 2012
We seem to be very close to affordable/cheap battery storage for the grid. Solar panels are getting very cheap. Wind generation is already cheap and getting cheaper. Hydro and geothermal produce attractively priced electricity.

A combination of ground-based wind/solar/geothermal/hydro/storage will create serious cost competition for orbital solar.

Let's spend some money to research it. We learn things from research. But I'm not betting that we'll figure out how to supply ourselves from space cheaper than collecting on the ground.

Remember, large amounts of power beamed down would have to then be distributed. It's going to be cheaper to locate generation/storage close to point of use than to move it large distances.
Burnerjack
1 / 5 (1) Apr 15, 2012
Bob ya'know what's NOT cheap? Orbital payload costs! Sure it's a one time cost, the proponents will say that's a one time charge. Theoretically true. Like the Hubble telescope? This a ridiculous attempt to get funding for a dead end endeavor at the expense of those concepts that are more virtuous. If there is any doubt, let private capital do it. But then if T. Boone Pickens, Burt Rutan, Sir Richard Branson and the like aren't interested, don't ask me, the taxpayer to do it either. Those days of absurd spending hopefully are drawing to a close (IMNSHO).
hariseldon
1 / 5 (1) Apr 15, 2012
Laser might be better if your pushing a photon sail, it can stay focused over a distance of light years. problem is that you need another one at the other end to slow down.

Niven and Pournelle, "Mote in God's Eye" 1974
jibbles
1 / 5 (1) Apr 16, 2012
forget beaming it to the earth...just brainstorming here ... but couldn't the collected light energy instead be focused on a specially designed spaceship -- perhaps making interstellar travel possible? the energy beamed from the sun would eliminate the need for on-board fuel --certainly for accelerating away from the sun, but also perhaps in reverse (see fairly recent physorg article on tractor beams). the beam might also help clear the particles in the spaceship's path that would endanger it once it's travelling at high speed...
jibbles
1 / 5 (1) Apr 16, 2012

If the satellite's orbit were at an angle to the ecliptic, it would never enter Earth's shadow, while remaining in an Earthbound orbit. There is no need for placing anything so far away at Lagrange points.

--- well, almost: the two planes will still intersect in a line, whose orientation will stay fixed as it is translated with the earth moon's center of mass around the sun. therefore twice a year the sun-earth line will coincide with this line, making a rare eclipse possible.
wwqq
1 / 5 (1) Apr 16, 2012
We can drill 8km for oil, repeatedly, but 6km for inexaustable CLEAN BASELINE power with proven off the shelf technology is a no-go? Really?! Why?


The hot water has ~1/50th the energy density of oil and the wells require hydraulic fracturing.

Oil is a very non-aggressive liquid to pump around.

Hot water has issues with corrosion, fouling by scale deposits and erosion from the much greater volumes of liquid you will have to pump.

Geothermal is very depletable; it is being replenished at an average rate of ~75 milliwatts/m^2. So what you're really doing is mining heat from a volume of rock; in 20-30 years it becomes uneconomic to operate the well and you go drill somewhere else.

If the well is left alone for a century(and miraculously remains in refurbishable condition) surrounding rock has heated it back up again. If you use this up you've depleted the surrounding rock as well and now you have to wait even longer.

Drilling only to 6 km is not enough in most of the world.
Prokinetik
3 / 5 (2) Apr 16, 2012
How exactly STUPID this is? To drill yet another hole through ozone layer, to burn the atmosphere with enormous amount of heat, to WASTE money that could be used for building whole lot more energy receiving stations on planet's surface, for what? To collect something we can collect FROM-EARTH?!? This action, as well as EVERYTHING about this entire ridiculous idea deserves immediate & complete shutdown!!
Burnerjack
1 / 5 (1) Apr 16, 2012
wwqq: Iceland gets the vast majority of their power this way. The Philippenes also have extensive geothermal power. Granted, these volcanic areas are ideal, but the point is 1)There are many, many areas in the world where this is possible(Pacific Rim comes to mind), Yellowstone, Washington State, Idaho, California and others are either already doing it or are in process. As far as fracking and lifespan goes, the deeper the well, the less both of these issues impact the process. The Hawaiian chain, for example might only need to go down 1-2 Km. Point being: Let's exploit what we already have available before leaving the planet. You think Orbital payloads are cheaper than drilling holes or utilizing abandoned wells already bored? C'mon, now, get real.
Musing AboutStuff
1 / 5 (1) Apr 16, 2012
A satellite to send power to Earth is a step in the right direction, but I have always thought about the following. I'm not in the field or even close to it, so I figure others have either thought of it and are working on it, or have thought of it and discarded it. But here goes anyway, in the spirit of crowdsourcing.

What about a two-phase approach:
1. Solar power plants on Earth that concentrate as much solar power as possible and server to alleviate the load for selected power grids. The could be built as close as possible to conventional power stations to supplement them.
2. Solar power plants on Earth or somewhere else in the solar system that charge commodity-hardware style batteries that can be shipped back to plug into "building batteries." This could be either the main power source for a building or a backup in case of power outages or peak demand.

I realize #2 has a lot of launch and transportation expense but wondering if it can somehow be made efficient enough to work.
TheGhostofOtto1923
1 / 5 (4) Apr 16, 2012
why are they using microwaves?in which orbit will it be supposed to launch.how much energy will be lost while transmission to earth receiving station.which materials will be used.can we use a micro wave laser?please replay to my questions
read the thread.this question already asked and anwered.if you want a reply try using normal punctuation so you don't appear like a dweeb.you think it is clever but it is just annoying you dweeb
TheGhostofOtto1923
1 / 5 (3) Apr 16, 2012
@prokatekink
What makes you think these will
drill yet another hole through ozone layer
or
burn the atmosphere with enormous amount of heat
or
WASTE money that could be used for building whole lot more energy receiving stations on planet's surface
-Sounds to me like you're not really interested in finding out
for what?
Obviously experts who have studied this in great detail think that it may make sense
To collect something we can collect FROM-EARTH?!?
-Right?
This action, as well as EVERYTHING
EVERYTHING
about this entire ridiculous idea deserves immediate & complete shutdown!!
Ha no it doesn't you dweeb.
Caliban
not rated yet Apr 16, 2012
Bob ya'know what's NOT cheap? Orbital payload costs![...]T. Boone Pickens, Burt Rutan, Sir Richard Branson and the like aren't interested, don't ask me, the taxpayer to do it either. Those days of absurd spending hopefully are drawing to a close (IMNSHO).


@burner,
Not picking on you, but this comment is a speaks to two issues: first, the need to nationalize the energy industry as a non-profit service, operated on cost-plus basis, with revenues above cost plowed back into ongoing structural upgrades and even R&D. Price volatility is eliminated. Pay out large prizes for research that increases efficiency by at least 1%. Self-sustaining industry that remains inexpensive. And doesn't depend on choice of technology at the whim of the so-called "free market".

contd
Caliban
not rated yet Apr 16, 2012
contd

Secondly, this issue of orbital payloading being so exhorbitantly priced: price will continue to fall, at least in the short term, precisely due to the efforts of Rutan, Branson, et al, even that douchebag Pickens.

Those guys are in the race because they smell a profit in Commercial Space Enterprise, and space will become accessible to us, at cheaper and cheaper rates in the near term, until the market matures enough to consolidate, at which point the trend will reverse.

Meanwhile, we get our stuff out there, develop the tech to live, work, mine, and manufacture in space, and meanwhile use some of that power to operate massive electrolysis of seawater to extract valuable elements along with LOX and H2, and BINGO! --there's the fuel to launch more orbit-bound payload.

By no means do we give up any efforts at co-generation. Any proven tech should be employed.

All that is necessary is to take enrgy out of the hands and control of the private, for-profit "free market".

antialias_physorg
not rated yet Apr 17, 2012
Secondly, this issue of orbital payloading being so exhorbitantly priced: price will continue to fall,

Prices for manned/construction missions have not fallen (and we're not going to get anything of that magnitude up without it)
The space shuttle program was specifically touted to get the costs of delivery of stuff to LEO down. Originally it was estimated that the (then, i.e. 1980s) cost of 200 million per launch would come down to 20 million per launch by using a resuable orbiter and boosters.
In the end the average launch cost of a space shuttle was 450 million dollars.

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