Preliminary Economic Comparison of Space Based Solar Power and Nuclear Power

[bananas]

As cost estimates for nuclear increase, SBSP looks better and better.
The comparison below used a WNA estimate for nuclear of $4,200/kW,
but official applications for federal loan guarantees averaged $6,500/kW,
Moody's estimated nuclear at $7500/kW last summer,
and more recently Severance estimated nuclear at $10,500/kW.
The estimate below is $15,000/kW for SBSP in 2015,
dropping to $6,000/kW for SBSP in 2024.

http://www.spaceenergy.com/Discovery/space_energy_files/SBSP_and_Nuclear_Power_Economic_Comparison_v2.pdf

Preliminary Economic Comparison of Space Based Solar Power and Nuclear Power
February 2009
Introduction

Space Based Solar Power (SBSP) is estimated to be an economically viable source of
clean and renewable energy that can utilized for mainline grid power, 24 hours a day. In
comparison to other forms of electricity production, it has advantages and disadvantages.
Space Energy will position SBSP as a valuable source of electricity, which will
complement other forms of electricity generation, in order to meet rising global demand.
Other than a strict economic evaluation, SBSP will also offer many significant
advantages to the countries that are early adopters of this technology. (More details on
request)

<snip>

[phantom power]

1. I don't believe their figure $15/watt.

Not at any realistic cost to put mass into orbit. To say nothing of maintenance.

[Massacure]

3. I agree with you on that.

The most commonly used figure is $10,000 a pound to put something into orbit. Just for fun I picked a random solar panel: a 210 watt model that is 37 pounds. That is $370,000 to put that into orbit. Granted a solar panel might be able to get twice as much sun in space as on Earth, but even if you cut the cost of putting something into orbit by 1/10th, it would still cost $90 a watt.

[bananas]

9. Launch costs are already lower than that, panels will be much lighter, and get 8 times the sunlight

http://en.wikipedia.org/wiki/Falcon_9
I'm too busy to dig out any other references.

[Massacure]

14. I remember reading about the Falcon back when I used to browse Space.com

Using Wikipedia though, a launch to low earth orbit is minimally $1300 a pound. A launch to geosynchronous orbit (which is probably more likey) cost at least $7,800 a pound. Those figures certainly beat anything done by a government agency, but are still too high.

BTW, I don't believe your 8 times figure.

[bananas]

17. I meant 8 times ground-based over 24 hours, not peak watt.

IIRC peak watt is only about 25% higher.

They only have to pay to get to LEO, from there it can propel itself to GEO.

Solar PV at 300 W/kg:
http://www.stretchedlensarray.com/
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V1N-4JS1MR4-5&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=6a332d5c7c2f09933812ba5ca0e47167
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APCPCS000699000001000875000001&idtype=cvips&gifs=yes

So we have roughly ($3,000/kg)/(300 W/kg) = $10/W or $10,000/kW

[NickB79]

18. How does a satellite propel itself from LEO to GEO?

Would the solar panels be used as a solar sail of sorts to boost into a higher orbit?

[Dead_Parrot]

21. Magic. nt

[OKIsItJustMe]

25. I believe the term is "upper stage"

http://en.wikipedia.org/wiki/Inertial_Upper_Stage

On the other hand, solar power could drive an http://en.wikipedia.org/wiki/Ion_thruster">ion thruster. (Right?)
http://nmp.jpl.nasa.gov/ds1/tech/sep.html

[Dead_Parrot]

27. I think you just added about 8 thousand tons to the beast...

...just for ion propellant: More if you use a conventional rocket stage. The extra thousand or so launches to LEO will not, I fear, save you a huge amount of money, since I think it's more than the entire world's space program to date just to fill the tank up.

The idea of firing someone into GSO to assemble it is mad, but a lot more sane than trying to launch and build a 40,000 ton self-propelled power station.

Incidentally, I wonder if anyone has compared the power requirements of producing 4,000 LEO lifters to the lifetime output of the station? the EROEI for this thing must be fascinating...

[Massacure]

28. Um, well.

Earth's escape velocity is 11.2 km/s. Which is 7 mi/s. Which is 36,960 feet per second. Kinetic energy is 1/2 (mass) (velocity) (velocity) so that is 683 million BTU minimum to put one pound into orbit. That is 25 billion BTU to put a 37 pound 210 watt panel into orbit that I mentioned in another post. So it takes 7.4 million kilowatt hours to put a 210 watt panel into orbit. Assuming only 50% of sunlight actually makes it to the ground on Earth and that solar panel puts out 400 watts 24/7, it would take more than 2000 years for it to come even on the energy required to launch it.

Ouch.

[Dead_Parrot]

29. To be fair...

... you don't want to hit full escape velocity, "just" punt the thing 22,000 miles up, so you're slightly over (by about 10%, IIRC).

But yeah, it doesn't seem the most efficient way of generating electricity....

[bananas]

32. The EROEI is very high

I don't have a link handy.

[Dead_Parrot]

35. O Rly? nt

[bananas]

31. Solar Electric Propulsion

Solar Electric Propulsion
http://en.wikipedia.org/wiki/Electric_propulsion
http://en.wikipedia.org/wiki/Solar_electric_propulsion

Study of space transportation for space solar power systems
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V1N-4KBDWC1-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=9bec927918b15c1f6098acfd294433d7

[Name removed]

30. Deleted message

Message removed by moderator. Click here to review the message board rules.

[OKIsItJustMe]

12. BBC: Skylon spaceplane gets cash boost

http://news.bbc.co.uk/1/hi/sci/tech/7898434.stm

Page last updated at 02:07 GMT, Thursday, 19 February 2009

Skylon spaceplane gets cash boost

By Jonathan Amos
Science reporter, BBC News

An innovative UK launcher concept is to get 1m euros (£900,000) of investment from the European Space Agency (Esa).

The Skylon spaceplane would take off from a conventional aircraft runway, carry over 12 tonnes to orbit and then return to land on the same runway.

The money will help prove the vehicle's core technologies, including its Sabre air-breathing rocket engine.

Reaction Engines, the company behind the project, believes its reusable launcher could fly within 10 years.

Alan Bond, the Oxfordshire firm's managing director, said: "Traditional throw-away rockets costing more than a $100m per launch are a drag on the growth of this market.

…

http://www.youtube.com/watch?v=jh3VKGwALcc

[Massacure]

13. The BBC gives no figures on cost per pound and it COULD fly within 10 years.

That is hardly convincing.

[OKIsItJustMe]

23. slash the cost … from US$100 to 700 million per launch, to just US$10 million

http://www.cosmosmagazine.com/news/2586/skylon-space-shuttle-just-ten-years-away

Skylon space shuttle just ten years away

Friday, 20 February 2009

by Claire Thomas
Cosmos Online

LONDON: A high-tech spaceplane that takes off from an ordinary runway, and will slash the cost of flying to space, could be just ten years away, say experts.

The Skylon plane – which garnered one million euros (A$1.9 million) in support from the European Space Agency this week – is designed to carry up to 12 tonnes of cargo into orbit and return to land on the same runway.

New age of exploration

The unmanned, 82-metre plane is totally reusable, unlike most current launch technology. NASA's Space Shuttle is partly reusable and can carry 24.4 tonnes of cargo to low Earth orbit, but has to be launched like a conventional rocket at phenomenal expense.

Skylon's designers estimate that their shuttle could slash the cost of launching into orbit from US$100 to 700 million per launch, to just US$10 million, and in doing so, encourage a new age of space exploration.

…

[OKIsItJustMe]

22. Flying a Reusable Space Plane Directly to Orbit

http://www.sciam.com/article.cfm?id=skylon-reusable-space-plane

February 20, 2009 | 6 comments

Flying a Reusable Space Plane Directly to Orbit

A tiny R&D firm toils steadily toward a ground-to-orbit vehicle that could pave the way for easier and cheaper access to space

By Steven Ashley

When Luke Skywalker jumps into an X-wing fighter and flies off into space in the Star Wars movies, he's performing a feat that is impossible today. Current orbital launchers are large, multistage affairs that combine the thrust of a series of throwaway rocket stages to escape Earth's gravitational clutches and send a small payload into the void above.

How much simpler and cheaper it would be if one vehicle could accomplish the same task and return intact, again and again. Such a reusable single-stage-to-orbit (SSTO) craft might finally enable regular, truly affordable access to space. But a practical SSTO vehicle is no easy objective. For decades it has been the holy grail for the many rocket scientists and engineers who have tried—and failed—to develop one.

The main difficulty lies in designing and building a vehicle light enough and powerful enough to reach orbit with a viable payload, explains Alan Bond, one of the more persistent of the latter-day grail questers. "Existing technology can't hack it," Bond asserts, "but it's not off by much."

Almost two decades ago, Bond and two veteran research colleagues formed a small R&D firm in Oxfordshire, England. Their company, Reaction Engines, Ltd., set out to develop an SSTO space plane called Skylon. The ambitious design is based on a novel hybrid jet–rocket engine concept that just may provide the necessary boost. Today, a dozen Reaction researchers are working to perfect the engine's key technologies.

…

[Dead_Parrot]

7. ...and then magic happens, and then...

The current state of the art for space based panels is the array on the Dawn spacecraft: about 80 W/kg. Current launch costs to GTO edge in at around $20k/kg, so $250/w is a more accurate¹ estimate.
---
¹ Excluding the manufacturing cost of the panels, structural components, beaming equipment, ground station, and firing some poor dweeb 22,000 miles into space with a spanner to bolt 12,500 tons of solar panel together.

[OKIsItJustMe]

8. Basic assumption, everything is lifted out of Earth's gravity well

http://www.nss.org/settlement/ssp/library/final-sbsp-interim-assessment-release-01.pdf

…

FINDING: In order to cost‐effectively build, operate, maintain and repair much larger SBSP systems, America needs to develop ubiquitous on‐orbit space operations, including on‐orbit assembly, highly‐efficient orbital transfer systems, and on‐orbit repair, maintenance and refueling capabilities.

• Some system architectures assume Low Earth orbit will become a primary assembly and transfer location for SBSP satellites constructed from terrestrial components, while lunar orbit, and the Earth‐Moon Lagrangian Points will become major locations of activity should lunar and asteroidal resources be used in the manufacture of SBSP satellites. As a result, despite significant autonomous, robotic, and tele‐operations used in in‐space assembly, operations and support will likely require substantial human and robotic operations throughout the Earth‐Moon system‐‐capabilities fully consistent with the transition of the U.S. into a true spacefaring nation.

FINDING: The SBSP Study Group found that a space infrastructure is likely to be nodal, and require significant upper stages, or space tug development. Solar Electric Transit Vehicles (SETVs) appear to be the most attractive and appear to have strategic value in their own right.

FINDING: The SBSP Study Group found that growth past a certain (perhaps even initial) stage is likely to require or make attractive the use of off‐Earth materials because of their abundance and significantly lower energy costs.

…

It's probably best not to assume that "rocket scientists" don't understand orbital physics. (On the other hand…)

[Dead_Parrot]

10. Basic observation: We don't actually have any off-Earth factories

In fact, it's been nearly 40 years since anyone went outside LEO. Adding in "first, build your moonbase, then..." to try and wriggle out of costs is as perfect an example of "insert magic here" that I've seen for years.

Still, I'll bite. Show us the cost breakdown for the SBSP asteroid mining colony, and we'll see how it stacks up against an AP-1000.

[Nihil]

19. Hmmm ...

If the assumptions of

1) cheap lifting ability
2) magic off-planet assembly ability
3) funds & energy to develop both of the above

are accepted here then why not for the disposal of nuclear waste?

Could there be a teensy-weensy bit of hypocrisy coming into play?

:think:

(And no, I'm not supporting nuclear dumping in space but just wanted
to point out that if the "magic hand-wave" isn't acceptable in one
potentially devastating GHG-free power source, it isn't acceptable in
any potentially devastating GHG-free power source ...)

[Dead_Parrot]

20. But if we did that...

...the facts wouldn't fit the required conclusion. And we can't have that, can we?

[bananas]

33. The main reason for not disposing of nuke waste in space is

that launch accidents will scatter the waste over large areas.
The space shuttle has a catastrophic failure every 60 launches,
after thousands of launches of nuke waste, Disneyland and Miami Beach
would become radioactive exclusion zones.

So no, there is no hypocrisy coming into play.

[Nihil]

34. I agree with that (as stated originally) but note that you don't address the real point ...

... namely the use of magic-wand assumptions to support
one "miracle solution" versus a different "miracle solution".

And yes, that *is* hypocrisy.

If you are so adamant that nuclear energy cannot be a viable
prospect for the future due to the lack of a suitable major
component (i.e., the "safe disposal" side where "safe" is
defined according to your particular views) then there is no
way that you (or anyone with the same views) can support this
slice of pie-in-the-sky just because it is PV-based as it is
even more lacking in several major components!

I might not agree with all of your anti-nuclear views but can
see where many of them come from (and yes, I *do* agree with
some of them) but the sort of crap in the OP scheme (not poster!)
is just pitiful - and incredibly hypocritical when offered as
some kind of real-world solution to the real issues of nuclear
power.

[bananas]

36. We don't need a "miracle solution"

we have a "non-miracle solution" right here: http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x191961

I've never said that nuclear energy cannot be a viable prospect for the future, I've said that I support research into 4th generation fission and fusion. I'm pragmatic, if the technologies for fission, fusion, or space solar develop to the point where they are cost-competitive without too many objectionable problems, then they'll be used.

Most of my "anti-nuke" posts have been warnings that the cost estimates for nuclear were way too low, and I've been proven right. Now that more realistic cost estimates are being used, I'll probably focus on other problems. For space solar, small proof-of-concept demonstrations are planned over the next few years, and we'll have a better idea of how viable it is.

[Nihil]

37. Maybe not but that's what this thread is about - the "miracle solution" of SBSP.

I've just replied to your link and agree that, if that can be carried
out, there is probably no need for "miracle solutions" (ok, this *does*
depend on the behaviour in the period of the implementation as to how
much the goalposts will have moved).

That whole discussion is however unrelated to this thread as the latter
was started with "SBSP looks better and better" and this is incorrect.
The only way that "SBSP looks better" than anything is with incredibly
vague hand-waves and currently unavailable assumptions.

> For space solar, small proof-of-concept demonstrations are planned
> over the next few years, and we'll have a better idea of how viable it is.

This is why I'm surprised at your support for it: it doesn't exist
and will not exist without *serious* funding - the sort that puts the
Yucca Mountain farce back into the pocket-money league.

That money, if sunk into terrestrial PV, would produce a positive benefit
*this year* never mind "over the next few years". The difference in scale
that the funding would produce is far more than the "loss" due to the
atmosphere that this whole scheme is supposed to be reducing.

Maybe it depends on how urgent you believe the situation is and how long
you think it will take to turn things around?
:shrug:

[bananas]

38. No, this thread isn't about a "miracle solution"

This thread is about cost estimates of a technology.
Some of the posters were unaware of progress in the technology.

The funding for the Falcon doesn't come from a budget for "energy" or "global warming",
it's being funded for other applications. India is funding its own
research into low-cost space access, and that's not for space solar, either: http://www.telegraph.co.uk/scienceandtechnology/science/space/5095909/India-plans-to-test-space-shuttle-in-next-12-months.html
Bob Bigelow is spending his own money on space hotels: http://en.wikipedia.org/wiki/Bigelow_Aerospace

It sounds like you want to stop funding R&D for everything except nuclear.
Do you think funding for polywell fusion should be cut off?
Do you think funding for stem cell research should be cut off?
Do you think funding for cancer research should be cut off?
Do you think funding for FDA and OSHA should be cut off?
Do you think social security payments should be stopped?
Do you think India and Bigelow should stop their aerospace research?

In the short term, we should install terrestrial PV,
but we should still support funding on other projects.

[Dead_Parrot]

39. "Miracle" doesn't even begin to cover it

The cost of space-grade solar panels (in case you hadn't noticed the ISS was recently upgraded) is $300 million for 30 kW. That's $10,000 per watt, or $10,000,000,000,000 per GW. ...but then a miracle happens...

The weight of current tech is around 12g/W: call it 10 to be nice and make it a round number. That makes the finished article 10,000,000 kg for the array, even if we ignore the control systems, GW magnetron and 1km-wide antenna: even if Falcon reach their target, that's $33,650,000,000 just to put the panels in orbit....but then a miracle happens...

Incidentally, that's 71,293,179,456 kg of RP-1 kerosene up in smoke to reach LEO. Even at the 46.2 MJ/kg of standard kerosene, that's 104.4 GWyr of energy pissed away before you've even bolted the bugger together.

Oh, and the xenon propellant to push it from LEO to GSO via ion drive is about $4.5 billion, 'cause it's rather expensive stuff. Just FYI.

So no, the EROEI isn't "very high", it's actually an exercise in fractions. And the chances of this totalling less than $15 billion in the next 200 years make the lottery look like a dead cert.

[Systematic Chaos]

40. I can haz pipe dream?

<a href="http://icanhascheezburger.com/2009/04/03/funny-pictures-litter-box-i-forgoted/"><img class="mine_3656035" title="funny-pictures-kitten-forgot-way-to-litterbox" src="" alt="funny pictures of cats with captions" /></a><br />see more <a href="http://icanhascheezburger.com">Lolcats and funny pictures</a>

[bananas]

42. Your numbers are wrong.

Even when they looked at this decades ago using heavier and less efficient technology, the energy returned was much higher than the energy needed to get it into orbit. If your EROEI result is an "exercise in fractions", you've screwed up your math. I've wasted too much time correcting people's math errors, I'm not going to bother with this one.

[bananas]

43. According to the 2007 NSSO report, energy payback is less than one year

see http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=193309&mesg_id=193313

[Nihil]

41. Not sure why you went off in this direction ...

> It sounds like you want to stop funding R&D for everything except nuclear.

Where did you get that?
The only way that "nuclear" comes into my posts upthread is to illustrate
how much the original post lacked in both information and viability.
A discerning reader might even have noticed how many times I actually
agreed with your anti-nuclear comments but even if you didn't, you are
still pulling your "it sounds like" from somewhere undesirable.

> Do you think funding for polywell fusion should be cut off?
> Do you think funding for stem cell research should be cut off?
> Do you think funding for cancer research should be cut off?
> Do you think funding for FDA and OSHA should be cut off?
> Do you think social security payments should be stopped?

WTF? Since when did *any* of the above get mentioned in my post?
What makes you think that I would even consider posting on any other than
possibly the first one in the E/E forum (or even that I have an opinion
on them that I'd bother posting anywhere)?

> Do you think India and Bigelow should stop their aerospace research?

I really don't give a shit what either party does with its own money.
Good luck to them. It still doesn't make any difference to the OP as,
short of one of them coming up with a Tinkerbell-powered lifter, it will
not make sufficient difference to the viability of "big solar arrays in
space beaming down to the surface" as an energy solution.

The only reason I am posting on this thread is that someone is trying
to garnish funding for a complete pie-in-the-sky project that is directly
comparable to a proposal for shipping snowballs to Hell ... and that so
many people seem to go "Ooh, shiny!" rather than think about the real world
issues involved.

> In the short term, we should install terrestrial PV,
Totally agree.

> but we should still support funding on other projects.
Conditionally agree. I don't think we have either the time or the money
to waste on subterranean snowball shipping schemes and the "study" in
the OP (along with the entire concept FWIW) is most definitely in this
category.

[Ready4Change]

15. I think they're too optimistic. But...

I think it makes more sense than some might think.

For one, on Earth, PV's don't get full sunlight for much of a day, not to mention cloud cover, rainy days, etc. Often you are lucky to get the equivelent of 5 hours (in my area 3-4) each day.

In even an equatorial orbit PV's would get at least 12 hours a day. It's actually a bit more, since they are orbiting at least 200 miles up, so they are out of Earths shadow more. They could also be placed in orbits where they would get well more than 12 hours a day. So right there you are talking at least 2-4 times as much power. Then you can also consider the far greater solar power available in orbit, since nothing is being lost to the atmosphere, as well as the potential to make use of wavelengths largely eliminated by that atmosphere. So space based PV's can be FAR more effective.

But getting them into orbit? Expensive. Maintaining them? Also expensive. On one hand they don't need to deal with wind and snow and rain. On the other they need to deal with HUGE temperature changes and have robust enough systems to deal with occasional hits from micro-meteors. (With that much surface area the odds of getting hit once in a while increase a lot.)

I suspect they won't be competitive with Earth based generation until the day we have space based industry. That's a long way off, I'm afraid to say.

[corruptmewithpower]

2. Ever see an insect fried via sunlight and a magnifying glass?

That could be us with this space based thingamajig when they push the button that converts the power beam into a death ray.

Honestly, nuclear power seems much less likely to kill us, even if the power beam satellite folks are on the up and up.

[bananas]

4. It's not that easy to focus

and if you're worried about things being turned into weapons,
don't underestimate the risks of proliferation:
http://nuclearrisk.org/
http://www.time.com/time/health/article/0,8599,1873164,00.html

[OKIsItJustMe]

5. You may want to read the proposal

http://www.nss.org/settlement/ssp/library/final-sbsp-interim-assessment-release-01.pdf

…

FINDING: The SBSP Study Group found that when people are first introduced to this subject, the key expressed concerns are centered around safety, possible weaponization of the beam, and vulnerability of the satellite, all of which must be addressed with education.

• Because the microwave beams are constant and conversion efficiencies high, they can be beamed at densities substantially lower than that of sunlight and still deliver more energy per area of land usage than terrestrial solar energy. The peak density of the beam is likely to be significantly less than noon sunlight, and at the edge of the rectenna equivalent to the leakage allowed and accepted by hundreds of millions in their microwave ovens. This low energy density and choice of wavelength also means that biological effects are likely extremely small, comparable to the heating one might feel if sitting some distance from a campfire.


• The physics of electromagnetic energy beaming is uncompromising, and economies of scale make the beam very unsuitable as a “secret” weapon. Concerns can be resolved through an inspection regime and better space situational awareness capabilities. The distance from the geostationary belt is so vast that beams diverge beyond the coherence and power concentration useful for a weapon. The beam can also be designed in such a manner that it requires a pilot signal even to concentrate to its very weak level. Without the pilot signal the microwave beam would certainly diffuse and can be designed with additional failsafe cut‐off mechanisms. The likelihood of the beam wandering over a city is extremely low, and even if occurring would be extremely anti‐climactic.


• Certainly both the rectenna and satellite are vulnerable to attack, just like every other type of energy infrastructure. However, it takes significantly more resources and sophistication to attack an asset in geostationary orbit than it does to attack a nuclear power plant, oil refinery or supertanker on Earth. The satellite is also very large and constructed of a number of similar redundant parts, so the attack would need to be very precise. An attack on the receiving antenna would probably be the least value‐added attack, since it is a diffuse and distributed array of identical modular elements that can be quickly repaired while the receiving station continues to operate. Nevertheless, the best routes to security are a diversity and redundancy of clean energy sources, and a cooperative international regime where those who are capable of damaging a SBSP system also have an interest in preserving the new infrastructure for their own benefit.

…

[corruptmewithpower]

11. Ok, I read it. I still think the potential danger is radically understated.

[OKIsItJustMe]

6. Space-based Solar Power Comes to Light

http://www.satellitetoday.com/via/features/Space-based-Solar-Power-Comes-to-Light_29932.html

Space-based Solar Power Comes to Light

Richard Kusiolek
March 1, 2009

The use solar energy is forecasted to soar in the next eight years as the world’s population looks for alternatives to fossil fuels. It is estimated the sun can provide 219 thousand billion kilowatt hours of energy a year for 6.5 billion people, but converting the sun’s energy into a usable form in a cost-effective manner has proven difficult. Can the satellite industry use its experience with solar arrays to forge a new energy market direction?

In 1941, Isaac Asimov published a science fiction short story of a space solar power system orbiting on geostationary orbit that would beam down from space usable electrical energy. While the vision has taken a few practical steps since that time, the satellite industry should play a key role in making this dream of large-scale solar power production a reality. "The solar industry was born out of the space industry," says Ron Pernick, co-founder of the research firm, Clean Edge, a research and consulting firm focusing on clean technology, "It came out of Bell Labs of the very early implementation of solar for the space industry because they had a very definite requirement for space and satellites. In many ways the terrestrial solar industry has the space applications to thank for really helping solar gestation for up to two and three decades before it was ready for prime time terrestrially.... They feed on each other. It is a virtuous loop. It is important to pay homage to the fact that today’s modern terrestrial solar energy has very much the space industry to thank," Pernick adds.

John Mankins, president of Space Power Association, a private, international organization that promotes space solar power, estimates with today’s technology the project would cost $10 billion and be in place by 2025. "Energy from a solar power satellite would be transmitted in a coherent beam of low-intensity radio or light energy. An individual receiver on the ground might receive anywhere from 200 to 400 megawatts of power, up to 2,000 to 4,000 megawatts of power," he says. According to Mankins, "the development of space solar power must be an international undertaking and the U.S. should definitely play the leadership role in pulling together that effort."

Several U.S. federal agencies — Department of Energy, NASA, Department of Commerce — have reviewed the concept and concluded that it had no flaws and could be built. The U.S. Department of Defense’s National Security Office has been reviewing the concept as a way of providing energy for global troop deployment. The U.S. Energy Policy Act of 2005 saw the largest budget increase for solar research in U.S. history (to $148 million), but that pales in comparison with two other efforts — the California Solar Initiative, a $3.4 billion project signed into law in August 2006, and Google’s plans to install solar systems in what would be the largest solar electricity corporate campus ever built in California. Internationally, Japan’s Mitsubishi Electric is taking a leading technology role in Asia, and Canada and India have expressed interested in such an electrical grid from space. Chinese, Japanese and European space agencies also are funding research-related space solar power energy projects.

…

[kristopher]

16. We're more likely to see high altitude wind power first...

Several approaches show lot of promise. This site summarizes the concept and players.
http://peswiki.com/index.php/Directory:High_Altitude_Wind_Power

Google funded this company with $10M.
http://peswiki.com/index.php/Directory:Makani_Power%2C_Inc._High_Altitude_Wind_Harvesting

[OKIsItJustMe]

24. I personally don't expect to see large scale orbital power within my lifetime

However, just as we need to plan for long-term threats, we need to plan for long-term opportunities.

[tinrobot]

26. Let's put solar on every rooftop first...

If we need more power, then start launching.

[kristopher]

44. ROFLMAO

Never have so many know-it-all nuke nuts been shown to be so wrong so quickly...
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x193309