Space Based Solar Power Within a Decade? 371
Nancy Atkinson writes "A new company, Space Energy, Inc., says they have developed what they call a 'rock-solid business platform' and they should be able to provide commercially available space based solar power within a decade. 'Although it's a very grandiose vision, it makes total sense,' Space Energy's Peter Sage told Universe Today. 'We're focused on the fact that this is an inevitable technology and someone is going to do it. Right now we're the best shot. We're also focused on the fact that, according to every scenario we've analyzed, the world needs space based solar power, and it needs it soon, as well as the up-scaling of just about every other source of renewable energy that we can get our hands on.'"
Yep (Score:4, Insightful)
The downside is that importing energy from space upsets Earth's balance - but hopefully the new energy can be used to help remove some of the uneeded, less useful energy (atmospheric thermal energy, I'm looking at you).
But the potential is enormous. Coating the sunny side of the moon with solar arrays would provide something like 20 TW of power if I recall correctly - several times the total energy consumption of the Earth today.
Re: (Score:3)
The downside is that importing energy from space upsets Earth's balance
My thoughts exactly. Solar power that wouldn't normally hit Earth redirected towards Earth? Global Warming!
Tiny effect (Score:5, Insightful)
Re:Tiny effect (Score:5, Funny)
If we position it right, we can make the earth a huge solar sail and push ourselves out to an orbit that will negate the heat trapped by greenhouse gases!
Re:Tiny effect (Score:5, Funny)
Is that you Professor Farnsworth?
Re: (Score:2)
the effect on the Earth's energy balance will be negligible compared to the effect
Says who?
20TW of energy is nothing to sneeze at, and it's got to heat up the air it's passing thru, causing significant (remember, 20TW of energy is a lot)) localized changes to the whole weather column, which can't help but reverberate all around the globe.
Such an idea makes for a great Asimov short story, but is impossible when real engineers and scientists start thinking of all the real ways that things could go wrong in th
Re:Tiny effect (Score:5, Interesting)
Interesting. When was the last time you used your microwave to make hot air? The hot air around a hot cup of tea doesn't count... that's heat from steam.
Having said that, I still think it's a bad idea. Who is going to aim the thing, what guarantees are there against bad aim, and who is going to be liable if 100,000 people get irradiated with low-power microwaves?
Just wanna know. That's all.
Hmmmm.... (Score:2)
Re: (Score:3, Informative)
You do realize that microwaves don't have any effect besides heating water (and other bipolar molecules) and causing sparks to fly off metal (which is how the energy gets collected)? They aren't scary nuclear radiation, they just make you uncomfortably hot. Make the beam wide enough and it won't hurt anyone or anything.
Re:Tiny effect (Score:5, Insightful)
But if you make the beam "wide enough", as you describe, it is also not practical because it takes up far too much area (far, far too expensive). If you want to make it practical, you will have to beam it at a concentration that you definitely don't want pointed at your kitchen.
I understand the difference between microwave radiation and, say, ionizing radiation. But sufficient concentration of either one will kill you, albeit in much different ways. And, as I was saying before: if you want to collect energy over a given area, and make it efficient, it has to be a significant amount of energy. Nobody is going to build a single receiver the size of New Mexico.
So I get it, okay? But even though I know my new microwave is 1200W (and I even know what that means), that doesn't mean I won't find you in your office and shoot your ass if your satellite regularly aims 50mW at my kids.
That's clear enough, isn't it?
Re: (Score:3, Interesting)
... and steam is composed of what ?
That's right, water vapour ! And what are those white fluffy things in the sky ? Ding ding ding ! Clouds made of water vapour. So heating the clouds produces a change in the local weather patterns, and as we all know, local weather is part of global weather.
This seems like a great way to start a hurricane.
Re: (Score:3, Informative)
Nope, the proposed frequency is the same as microwave ovens.
http://en.wikipedia.org/wiki/Solar_power_satellite#Wireless_power_transmission_to_the_Earth [wikipedia.org]:
To minimize the sizes of the antennas used, the wavelength should be small (and frequency correspondingly high) since antenna efficiency increases as antenna size increases relative to the wavelength used. More precisely, both for the transmitting and receiving antennas, the angular beam width is inversely proportional to the aperture of the antenna, measured in units of the transmission wavelength. The highest frequencies that can be used are limited by atmospheric absorption (chiefly water vapor and CO2) at higher microwave frequencies.
For these reasons, 2.45 GHz has been proposed as being a reasonable compromise. However, that frequency results in large antenna sizes at the GEO distance. A loitering stratospheric airship has been proposed to receive higher frequencies (or even laser beams), converting them to something like 2.45 GHz for retransmission to the ground. This proposal has not been as carefully evaluated for engineering plausibility as have other aspects of SPS design; it will likely present problems for continuous coverage.
http://en.wikipedia.org/wiki/Microwave_oven#Principles [wikipedia.org]
A microwave oven works by passing non-ionizing microwave radiation, usually at a frequency of 2.45 gigahertz (GHz) (a wavelength of 12.24 centimetres (4.82 in), through the food.
(Emphisis mine)
There is also some infared wavelengths that can be used, but IIRC, they're less efficient.
Re:Tiny effect (Score:5, Funny)
who is going to be liable if 100,000 people get irradiated with low-power microwaves?
I can see it now... A bag of microwave popcorn will be the canary of the 21st century:
Oh my god Ellie Mae! The Bag's poppin'! Get the kids indoors and make sure they got their tin foil outfits on!
Re:Tiny effect (Score:5, Funny)
who is going to be liable if 100,000 people get irradiated with low-power microwaves?
Oh, I know! Motorola and Nokia, right?
Re:Yep (Score:5, Insightful)
Re:Yep (Score:4, Interesting)
Re: (Score:2, Informative)
Yeah sounds pretty hard, fuck it. Thankfully we had the smartest person in the world to indicate the error of our ways. Thanks OP!
Re: (Score:2)
I thought they were researching low-gravity manufacturing. The original idea was to construct everything with robots, on the moon?
But maybe that was a different company... I can't remember.
Green (Score:2, Interesting)
The "greens" will never let it happen. They already go nuts when a wind turbine wacks the occasional eagle. Can you imagine the "environmental studies" needed to cover FLOCKS of birds flying through the microwave download beam?
Greenpeace: Stopping progress one idea at a time.
Re:Green (Score:5, Insightful)
And the parent comment is NOT a troll. The environmentalists will say we don't understand the effects of transmitting concentrated high-power microwave beams from space down through the upper atmosphere to the earth's surface.
Will it affect migrating birds? Plants and wildlife in the area? Disrupt weather patterns? Cause unforeseen chemical reactions in the upper atmosphere?
And the sad part is that they're right. We probably don't know all of the consequences...
Re:Green (Score:5, Insightful)
The parent comment IS A TROLL . Look up the definition of trolling. I think you are getting "confused" since the troll stated something moderately insightful (if not obvious) that there would probably be demands from some environmentalists to conduct some sort of environmental impact study. Clearly you agree that environmentalists would make such demands and that the troll was merely stating an unpopular opinion/position and was moderated unfairly. However, what else did he/she say?
Firstly, he/she is comparing all environmentalists to members of Greenpeace. Secondly, he/she makes disparaging statements about Greenpeace. That was about 2/3rds of the troll's post. Labeling all people opposed to the technology, then making a comment about the difficulty(or unreasonable nature) of the impact study, and finally accusing a specific group of shortsightedness and obstinate attitudes towards progress.
Nothing productive was accomplished in that post and it only served to defame a particular group of people and their agenda. The only supportive comment was made in support of the derogatory comments themselves. The whole tone and purpose of the article was provocative while providing no clear positions or arguments. That is, by definition, trolling.
For full disclosure here, I am not a member of Greenpeace or any PAC with environmentalist agendas either.
Also, I don't understand opposition to environmental impact studies. It's shortsighted to have a manifest destiny approach to everything we do. Does it give us a little convenience and pleasure? Fine. Then "fuck all the little animals cuz i'm human and they were put here for me". Progress does not have to occur at any cost. Sure, the planet may seem big to many people. However, we are finding out rather quickly that our actions ARE changing the environments and animal and plant life that we cohabit with. I'm not talking about Global Warming either. Just making the simple statement that our actions have consequences and it would be prudent to understand them to the best of our ability before proceeding.
That's why I like the movie Rapa Nui, which is about the events on Easter Island. They ended up killing themselves and their local environment by their actions. If they had the sophistication to conduct and environmental impact study they would have quickly found out their actions were suicidal. Which is why these environmental impact studies are conducted (in my mind at least) to assess what damage we may do the environment in order to properly weigh the benefits versus the risks to not only the environment, but us as well . If it's just too damaging to the environment and we run the risk of endangering a species than it had better be pretty damn important. I want to know that it is something that will allow us to make positive progress. The comment about the eagle getting whacked is ridiculous. I don't think anyone is opposed to the renewable energy produced because of the possibility of a bird flying into the turbine. After all, the renewable energy itself is about sustainability and pollution free energy production which only benefits the environment anyways.
Lastly, we can never know all the consequences of anything. We are just not that sophisticated yet. Personally, I just want to know that all the little squirrels are not going to grow huge tumors on their nuts. It's not that much of a leap to conclude that tumors will grow on MY NUTS TOO.
Re: (Score:3, Funny)
I bet the in-side is pretty dark.
I LOVE stories like this (Score:5, Insightful)
It puts a smile in my heart because, at the end of the day, if we have enough extra resources in this country that we can afford to put them into such a ridiculous scheme, then the recession still isn't nearly as bad as it could be.
Awesome. Props to those salesmen.
Re:I LOVE stories like this (Score:4, Informative)
Re: (Score:3, Informative)
50 tons of gold would be worth approx. $1,558,720,000
Cost of 1 shuttle launch $450,000,000
Ok so some math here, let me see carry the 1...
Ok that leaves us with a measly $1,108,720,000 ok your right fuck that idea, thats not worth it at all... hehe
Re: (Score:3, Insightful)
Gold (like any other precious commodity) is worth exactly how much people are willing to pay for it. And the reason they pay so much is precisely because it is precious i.e. there is a limited quantity of it going around.
You start bringing back 50 tons at a time (and making a tidy 1 billion profit), and you'll see that the price of gold drops through the floor and it would quickly become as worthless as oil currently is.
So no it probably ISN'T commercially viable, at least once the gold buyers figure out wh
Re: (Score:2)
Errr.. Thank you Chauncey Gardiner. [wikipedia.org]
Re: (Score:2)
While a launch might only (hahahaha only) cost 60 million you can't just ignore all the development and production costs that went into producing the craft. That would be like a business saying to it's bank: if I don't repay my start up costs I'm profitable. I think I know what the bank would say.
MODS (Score:5, Insightful)
This project is an orbiting white elephant that would take an enourmous amount of energy to build, would supply only a tiny fraction of what we need at a ridiculously high cost per watt, and could easily be percieved as a space based weapon by other nations. If I didn't know better I would have to assume TFA is a lame attempt to discredit the viability of earth bound renewables.
Here is the sales pitch on costs: "The biggest challenge for SBSP is making it work on a commercial level in terms of bottom line," said Sage, "i.e., putting together a business case that would allow the enormous infrastructure costs to be raised, the plan implemented, and then electricity sold at a price that is reasonable. I say 'reasonable' and not just 'competitive' because we're getting into a time where selling energy only on a price basis isn't going to be the criteria for purchase.
This is total bullshit, cost is the ONLY criteria for commercial electricity generation, the fact that the costs to the environment are not accounted for in our current economic system is the problem.
MOD PARENT UP!! (Score:4, Insightful)
100% agreed, and there's no way that the launch costs are going to drop by the 3 orders of magnitude required to make this viable. I presume that his is an effort to extract "stimulus" money while the extracting is good, then fail later out. Someone will end up a millionaire and nobody is going to get any damn space power.
Brett
Re: (Score:2)
*me* - checks for full moon...
Obvious by it's absence (Score:4, Informative)
Notably they fail to mention what is expected to be the long pole in the tent - launch costs. Even if Musk and SpaceX succeed, launch costs will still be at least an order of magnitude higher than what is estimated will be required for commercial success of space based power plants.
Re: (Score:2)
Costs, you can cover by scamming trustafarian hippies. Good luck to them.
What matters is energy. We need to see the break-even time when the energy delivered to the ground exceeds the energy used in putting the thing up there - and yes, we're including the energy costs of the raw materials, production, and the ground based maintenance and monitoring, as well as the boom-juice to get the mass up there.
Want to bet that the break-even is longer than the realistic lifetime of the satellites?
Re: (Score:2)
for a "grown-up" system I can't see how anything except a geostationary orbit would be practical, otherwise you have to have the power beam continually tracking your target (word used adv
Feasible, but practical? (Score:3, Insightful)
Whenever I see space-based solar power I never believe its economically viable. Based on that quote, they recognize that its not viable in the current market, and that average energy costs would have to increase by a factor of 15 to 20 times in order to make it viable. They think that the trends in energy cost are going to go that way. Somehow, I think as energy costs increase we'll get more creative on the ground, expanding ground based solar power, wind, nuclear, geo-thermal, etc., improving efficiency and developing new technologies to bring those costs back down.
As others have pointed out, launch costs are the critical, incredibly expensive aspect. In order to make it practical, we need to drastically reduce the access cost for space, by at least an order of magnitude. None of SpaceX's most optimistic estimates, or anyone elses, make it more viable.
However, there is a practical path for development of SBSP in military applications. A few satellites and some trucks with microwave receivers on the back are very appealing when compared with the current method for generating battlefield power: supply lines hauling in diesel fuel to power good old-fashioned generators. SBSP has great tactical advantages, and may actually be comparable in cost as well. From here, we may very well see it gain civilian applications as well.
Re: (Score:3, Informative)
I noticed that too. In particular, the comment about shipping energy around the national (and, conceivably, international) grids.
I suppose one advantage of SBSP is that the aim on the satellite transmitters could be adjusted to one of several ground receiving stations, which would allow the power to travel over smaller distances on the grid. Whether this could actually make up for inverse square losses due to longer transmission paths, I don't know. Still, it's an interesting advantage to SBSP that I hadn't
Re: (Score:2)
I would agree with you on how useful this would be for Military Applications... just look at what doors GPS opened up.
The economics are bullshit (Score:2)
Based on that quote, they recognize that its not viable in the current market, and that average energy costs would have to increase by a factor of 15 to 20 times in order to make it viable. They think that the trends in energy cost are going to go that way.
No matter what happens to energy costs, space based solar cannot outcompete ground based solar. Space based solar can collect roughly twice as much power as ground based. (It's lit twice as long because there's no night, gains a bit from not having atmo
Re: (Score:2)
Microwave beams from space being directed to a truck in the middle of a friendly camp. Brings a whole new meaning to the term friendly fire.
Nuclear, please. (Score:5, Insightful)
This is silly. Putting solar panels in orbit? Please.
Use the money to build nuclear plants. Don't bore me with the waste issue. There is no such thing as waste, just more fuel. [theoildrum.com]
Other benefits (Score:3, Insightful)
Other benefits might include transmitting the power to remote locations where generation or transmittal is otherwise difficult (Antarctica for example), and more efficient power distribution on the power grid. If the power could be transmitted to different sites without significant loss, I^2xR losses in power lines across the grid could be minimized. Of note would be peak hours, and sunrise/sundown. I'm not sure what the power usage graphs look like, but I'm assuming there's enough fluctuation that it would be useful to shift power as the time of day changed.
Military applications (Score:4, Informative)
To deliver power to a certain places in Iraq and Afghanistan it costs well over $1USD/kWh, not mention the loss of human life.
The pentagon is seriously considering SBSP as a viable way to deliver power to not only these locations, but other places of humanitarian interest.
The technology to deliver and deploy SBSP payloads (for it will take many deployments) already exist. Improvements will undoubtedly be made, and with the hopeful completion of NASA's Ares V [nasa.gov] cargo launch vehicle SBSP will be economical for the rest of us. (under 20cents(USD)/kWh.)
As for the microwave radiation concern, it is not as scary as commonly depicted. (Can anyone recall the tale of the discovery of microwave radiation as a cooking tool--something to do with a Snickers bar melting in a pocket? [Who the heck carries a Snickers bar in their pocket?]) If the size of the receiving antenna is increased, the power of the transmitted signal may be decreased on a W/m scale. With a transmitter that can 'dither' the signal over a rather wide swath one can abate errors associated with tracking, solar anomalies and human error.
Military applications, however, are not quite as concerned with stray microwave beams.
Do not forget that SBSP is exposed to the sun for 24 hours--no interruptions!
On another note the Japanese are working on developing devices that may convert solar energy to transmittable energy in upwards of 40% efficiency by converting solar power to laser. [treehugger.com]
Re: (Score:3, Funny)
Even if it's only for a minute or so and there are no sharks involved, I'm sure the military will still find a use for it
200 Gigawatts? (Score:2)
Within a decade? (Score:2)
Round Collectors (Score:2)
Pie in the sky?
Re: (Score:2)
The renderings in the article show round or hexagonal collectors that seem to be radially divided into identical slices.
Pie in the sky?
Lies!
Re: (Score:2)
The renderings in the article show round or hexagonal collectors that seem to be radially divided into identical slices.
Pie in the sky?
Lies!
No no no!
The cake is a lie!
C'mon, get it right!
Exactly what we need! (Score:2)
Yah, that's exactly what we need. Huge solar panels out in space sitting out there just waiting to get hit by something and end up being smashed into pieces resulting in more orbiting space trash.
If we're going to do this, we need to re-invest in "StarWars" so we can vaporize any space trash that's out there. Or better yet create automated robots stay in orbit and clean up the orbiting trash for us and compact it and eject it towards earth to burn up (think Wall-E except in space instead of on earth).
Business costs? (Score:3, Insightful)
Let's see the practicalities here:
1) Finding funding for building solar panels in space taking into account space insurance, multiple launches, space walk fees by NASA, etc.
2) Microwave power that can possibly fry the contents aluminium cans with wings that fly all over the world? It requires dedicated road to space. That costs money in many ways: First of all congressional critters and senators have to bought to introduce an amendment that would allow FTA and FCC to provide an exemption to existing air occ
Economical? How? (Score:3, Insightful)
Am I the only one who doesn't quite see how they intend to make this profitable?
I assume they're planning on geosynchronous orbit (the article mentions they are), since anything else will mean intermittent power and moving collectors. In that case, the typical launch cost is $20,000/kg, and the there are serious total weight restrictions per launch. Solar cells come in two varieties: Heavy and inefficient. Trucking and installation costs of solar cells here on Earth are what, $200/kg, if that?
The big advantage? Something like 3x the total incident power per unit area. Even if they somehow get more power (by utilizing UV light, for example, which the atmosphere mostly absorbs), you can't ignore transmissions losses, which are going to be nontrivial from geosynchronous orbit.
So let me get this straight... they're planning on spending about 100x the cost of a terrestrial system for 3x the power gain? Wow, what a business case! Let me sign right up, I want to buy their stock *NOW* before anyone else gets wind of this!
Even if we're incredibly generous and let them have a 10x reduction in launch costs (wishful thinking), then they're still off by a factor of 3x from matching, let alone beating, terrestrial solar power costs.
And no wait.. I forgot.. they still need a stupid huge ground station to collect the power! So, all that money they saved having to install ground based equipment? Still have to spend it! My back-of-the-envelope maths (probably wrong) is that if they use a 1 mm wavelength microwave beam, they're looking at a receiver over 1 km wide due to diffraction limits. Mmm... cheap.
It's just inverstor and stock buzz! (Score:3, Insightful)
Wireless power transmission? Not yet possible!
Wired power transmission? Only in low-end comics and sci.fi.
Ground based receiving plant? Not yet designed!
Security? Not even taken into account!
Money from investments and stock markets? Yeah!
Assumes massive increases in energy costs. (Score:2)
Sage said SBSP will never be cost comparable with the current going rate of 6 or 7 cents a kilowatt due to the enormous set-up costs
The proposer of this scheme also says that "there are times in the US when electricity is sold wholesale for close to a dollar a kilowatt" so it looks like this is the market they're going after.
For it to be viable, therefore, there would have to be many occasions when this spot price was reached. If that's the case, I'd prefer to go with ground based solar for my personal electricity supply, rather than being dependent on a single[1] satellite up there beaming energy in my genera
Planet Earth had vast deserts, last time I checked (Score:2)
Admittedly the energy harvest per square meter of solar cells won't be as much as in space, but arrays built in a literally more down-to-earth way are probably just a little more accessible
Crazy units (Score:3, Informative)
"Almost 200 million gigawatts of solar energy is beamed towards the Earth every second, which is more energy than our civilization has used since the dawn of the electrical age."
Let's see. 200 million gigawatts * 1 second = 0.2 exajoules. Worldwide energy consumption is on the order of hundreds of exajoules per year.
This article must be using the wrong units somewhere, but I guess that's just the status quo nowadays.
useless (Score:2)
Space based solar power is a useless idea. The earth's atmosphere is quite transparent to light, so you don't gain much by moving outside it. If you do everything right, you gain up to a factor of two because you can stay in sunlight much longer. But to get that modest improvement you pay many orders of magnitude more in transport and maintenance costs.
The biggest issue with space-based solar power, however, is that you're giving someone access to megawatts of power ready to be aimed at any point on the
Re: (Score:3, Insightful)
The earth atmosphere is quite transparent to what humans usually call light. that is, visible light. a very tiny portion of the spectrum.
But, the sun emit much more than visible light. If you can use UV or higher frequency, or perhaps a wider spectrum, then you get a lot more energy than the equivalent setup on earth.
And, I agree with the other parts. Once you have your nice space-based energy collector, then you have a lot of energy, in space. it would be nice to find a way to take it back to places that u
What could possibly go wrong? (Score:2)
Well, I guess it might be OK just so long as he doesn't pitch the planet into eternal darkness because of all the shadowing solar cells. Perhaps they should set them up on a exterior ring to capture the light that hasn't landed on the planet.
But that would be a rock solid business model: We'll capture all the suns energy and sell it back to people so they can have light and heat.
The other concern is the debris. Aren't these things going to be pulverized by all the debris that we have up there? This is be
Do the math, folks (Score:3, Insightful)
Let's do the math on this one.
Let's say we want to put up enough PV cells to replace just one largish power plant, say 1GW.
Using conservative estimates, and assuming everything works perfectly the first time, I get a cost per kilowatt-hour of close to $8.
That's mighty steep, like 80 times the going wholesale rate.
The numbers for those interested in such minutea:
watts delivered 1,000,000,000.000
conversion to AC 0.950
DC needed 1,052,631,578.947
uwave to DC 0.850
AC needed 1,238,390,092.879
Receiving ant. Eff 0.750
To recv ant. 1,651,186,790.506
Atm loss 0.900
from sat 1,834,651,989.451
xmt ant eff 0.900
to xmt ant 2,038,502,210.501
uwave gen eff 0.750
DC to uwave gen 2,718,002,947.334
Solar cell eff 0.150
Watts to s cell 18,120,019,648.896
watts per sq meter 1,400.000
avail of light 0.600
watts avg 840.000
sq meters needed 21,571,451.963
weight per sq m 5.000 lbs
cell weight 107,857,259.815
$/lb to geo $5,000.00
cost to lift $539,286,299,074.30
lbs/watt gen 0.010
lbs gen 27,180,029.473
cosrt cells/sq meter $1,000.00
cost cells $21,571,451,962.97
gen cost/watt 1.000
gen cost 2,718,002,947.334
tot cost 563,575,753,984.601
time to build 5.000 yrs
cost of money 5.00%
int factor 0.250
cost fin 704,469,692,480.751
yrs runs 10.000
cost/yr 70,446,969,248.075
kw gen 1,000,000.000
hrs/yr 8,766.000
kwh/yr 8,766,000,000.000
cost/kwh 8.036
current cost/kwh 0.100
overrun factor 80.364
Re:Do the math, folks (Score:5, Informative)
Parent post is good, but it's really much simpler than that.
Cost per kg to send something to GEO orbit: $10,000
Cost of solar cells per kg: $400
Space-based cells produce about twice as much energy as the same panels on the ground.
So until launch costs drop to equal to the cost to build the panels, it'll be cheaper to just build twice as many panels on the ground.
Space-based power is a factor of 20 away.
Re:So long cables running from space to earth? (Score:5, Informative)
you clearly did not RTFA. microwave.
Re: (Score:3, Interesting)
Re: (Score:2)
Hello fellow Gundam 00 fan!
Re:So long cables running from space to earth? (Score:5, Informative)
Re: (Score:3, Informative)
Umm, you are so wrong, one of the power plant options was satellite microwave. I remember it clearly, and it's mentioned in the wikipedia entry [wikipedia.org]. Obviously you don't get to build the space based part, just the ground based receiver. As I recall, it was an expensive option and I rarely used it.
Re:So long cables running from space to earth? (Score:5, Funny)
If SimCity 2000 is anything to go by this venture will result in a massive fire, followed closely by an alien invasion.
Re: (Score:2)
Here's a good link demonstrating the capability of wireless power transmission.
http://www.spaceislandgroup.com/biz/NASAPowerP1.mov [spaceislandgroup.com]
Re:So long cables running from space to earth? (Score:4, Informative)
Re: (Score:3, Informative)
It seems like it could be made pretty safe. Have the receiver constantly sending a keep alive signal back to the satellite as long as the power beam is on target. If the beam drifts off target for any reason, the keep alive stops, and the satellite will stop sending down energy until it can be properly realigned. It does mean that you lose power for a bit, but that's probably preferable to losing power AND nuking some poor schmuck's house.
Re: (Score:3, Informative)
You know how the latency in a satellite kills that way of communications for gaming, correct? Considering that light travels 180,000 miles per second, and that geostationary satellites are 20,000 miles away minimum, that is a good fraction of a second where the satellite can be knocked out by space debris or what not. Imagine the swath it's aiming at with just a small degree, we are probably talking at least dozens of miles.
OTOH, the energy would be distributed along that entire area, but still.
Re: (Score:3, Insightful)
I don't think latency would be an issue. You don't need to time stamp the signal, just hear it. From the satellite point of view the break in signal would be instantaneous once it lost line of sight, even if that signal spent 2000ms to get there.
Re: (Score:2)
Have the receiver constantly sending a keep alive signal back to the satellite as long as the power beam is on target. If the beam drifts off target for any reason, the keep alive stops,
Clouds, humidity, storms, LEO debris flying thru the beam, the Earth's rotational wobble, the Moon's tidal effects, and probably a dozen other factors I haven't thought of will all affect aim and focus, plus availability.
And what about when it breaks? There goes a large fraction of a country's electrical power.
Re:So long cables running from space to earth? (Score:5, Insightful)
That applies to any power source you can think of. The usual solution is to have some spare capacity to cope with such situations.
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
The trick is to build the receiving stations out in the desert or places where missing by a degree or two isn't going to incinerate Small Town, USA.
Re:So long cables running from space to earth? (Score:4, Informative)
If this article can be believed it's hardly as dangerous as you're making it out to be.
http://permanent.com/p-sps-bm.htm [permanent.com]
Re: (Score:2, Interesting)
A rectenna is much cheaper per m^2 than a solar cell.
Re: (Score:3, Interesting)
A rectenna is much cheaper per m^2 than a solar cell.
And 3 times as efficient.
Re: (Score:3, Insightful)
Re: (Score:2)
Why bother with a nuke? You don't need anything approaching large yield to take out a satellite. A standard Air-to-Air warhead would do the job fine...
Re: (Score:3, Insightful)
The weapon abuse is small, since turning a massive satellite takes time.
So don't turn the satellite. Turn the emitter.
Re: (Score:3, Informative)
How exactly are they going to get the power back down from space?
Microwave transmission [wikipedia.org].
Re: (Score:2, Funny)
Re: (Score:2)
All they need are a couple of solar panels and a bunch of extension cords. I don't know about the solar panels, but home depot has 50ft extension cords that look pretty sturdy for only $20, and for the 20,000 of them or so that you would need I'm sure they could work in a discount.
You forgot to account for the duct tap to hold it all together with.
Re: (Score:2)
They'll store it as static on balloons by rubbing them vigorously, then the balloon will be popped and fall back to earth to be discharged. Replacement baloons will float up to the generator by using helium.
Re:So long cables running from space to earth? (Score:5, Insightful)
Actually, you're wrong, the real question is why the hell are you up there in the first place trying to get power? There are literally thousand of square miles here on earth where you can put solar power panels that are 10,000 times cheaper. Yes, they may drop to 33% efficiency compared to an equivalent panel in space due to atmospheric absorption/reflection of the light. Yes, you may have to clean the solar panels here on earth more often, but there is nothing here that makes up for a 10,000 to 1 installation cost difference.
Until someone can explain that, this whole business model is all pie int he sky BS. This doesn't pass the laugh test.
Oh... and once you handle that hurdle (good luck), THEN you have to deal with the "how do you get it back to earth" question in a way that *maintains* the 3x power advantage you gained by being up there in the first place.
d
Re: (Score:3, Interesting)
The problem with massive arrays of otherwise unused areas is the lack of global electricity grid to deliver the power from, for example, the desert to where the big cities are without massive losses on the way.
A space based power system has the advantage that the receiver can be placed near (*1) the population centers.
note 1: as near if not nearer than a nuclear power station for example.
Re: (Score:3, Insightful)
I'm afraid you're wrong on this one. Low earth orbit is defined as 100 miles to 1240 miles (according to wikipedia). So the *closest* you can possibily get with a satalite is 100 miles... now the problem is that if you're 100 miles above the earth you have to be spinning around the earth at a tremondous speed in order to stay in orbit. This means you can't really aim your power sending beam of whatever (uwave in this stupid article) at a single base station and you've got to be rotating A LOT to keep ai
Re: (Score:3, Informative)
There are NOT MASSIVE LOSSES IN THE GRID! "Although losses in the national grid are low, there are significant further losses in onward electricity distribution to the consumer, causing a total distribution loss of about 7.7%.[6] However losses differ significantly for customers connected at different voltages; connected at high voltage the total losses are about 2.6%, at medium voltage 6.4% and at low voltage 12.2%.[7]"
-- http://en.wikipedia.org/wiki/National_Grid_(UK) [wikipedia.org]
Re: (Score:2, Informative)
This isn't an ion cannon. The effects at the transmitter are minimal, so I'd expect they won't do much to a satellite.
http://permanent.com/p-sps-bm.htm [permanent.com]
Re:Space debris? (Score:4, Interesting)
This is probably why they have Feng Hsu [spaceenergy.com], NASA's head of Risk Management for Safety and Mission Assurance, at the top of the list of experts they have helping advise the project. While I'll agree with what another poster said, most of the website reads like marketing towards investors, they do at least have some real experts involved and are serious about attempting this.
Personally I hope they succeed (and that they're hiring when I finish school).
Re: (Score:2)
Helping advise == Had a business lunch together.
Re: (Score:2, Insightful)
Re: (Score:3, Informative)
Nobody cared during the life of Nikola Tesla.
Although his idea was that everybody/everything would have a collector antenna to tap in. Not very commercial for him, the project was stopped.
Yes, granted the are gigajoules sent the Earth every s, for *free*, its still far to be the salvation from fuel...
Not so much... (Score:5, Informative)
First figure that the cost of putting a kilo in orbit is NOT going to go below $300, period. Not if you're lifting stuff into space with any sort of chemical rocket. So the cost of a kilowatt of SPS power is going to be MUCH higher. OK, you're PV cells are lets say 400% more efficient, but then you also have to build a giant rectenna or 10 and losses beaming power back to Earth then eats up 50% of your efficiency gains, so hey, it is only 10x more expensive than putting it in Nevada!
The other problem is we still have no idea how to build really large structures in space. Obviously it can be done, but anyone who thinks the basic engineering of that solution will not cost 100's of billions of $ is well, another O'Neil, and if he was even order of magnitude on with his numbers it would be happening now. It is a lot harder than people think. It is a lot harder than engineers think (who usually only underestimate by about 300%).
What we need is HUGE quantities of power. The US needs 15 TERAWATTS of renewable energy installed base in the next 20 years. The gating factor is cost, not efficiency. Instead of screwing around for 20 years figuring out how to build it in space, for no clear benefit, we need to just BUILD IT NOW. Time is a wasting.
Re: (Score:3, Insightful)
The estimates I've seen put the lifespan more within 20 years, which is too short to make an economic case.
Like GPS, the first group to do SBSP is probably going to be the military, since they have reasons for getting power into remote areas that aren't strictly economic.
Re: (Score:3, Insightful)
No, the 15 Terawatt estimate is assuming a fairly good level of efficiency gains already. I'm not going to throw out numbers off the top of my head, but you can easily find this data in various places online. Plenty has been written about it.
So if you want to go much below 15TW then you are going to have to tell people they can't do stuff, and that is what is called an 'unelectable candidate in the USA'.
I understand where you're coming from, and I agree that efficiency is the #1 way to get out of this jam w
Right! (Score:3, Informative)
All we have to do is put a gigaton or so of unobtainium into geosynchronous orbit and then weave a cable 35,000 miles long out of it, lower it to the Earth, and then figure out how to make a vehicle that can climb a cable for 35,000 miles.
Worse yet, if we fail it is a serious problem. We can't even build suspension bridges with 100% reliability. Whoever thinks we're going to build a beanstalk right on the first try is probably wrong.
I put beanstalks into the 'who knows what might be possible in a century or
Re: (Score:3, Insightful)