Space Solar Power Limitless clean energy from space

[and-justice-for-all]

http://www.nss.org/settlement/ssp/

About Space Solar Power (SSP, also known as Space-Based Solar Power, or SBSP):

The United States and the world need to find new sources of clean energy. Space Solar Power gathers energy from sunlight in space and transmits it wirelessly to Earth. Space solar power can solve our energy and greenhouse gas emissions problems. Not just help, not just take a step in the right direction, but solve. Space solar power can provide large quantities of energy to each and every person on Earth with very little environmental impact.

The solar energy available in space is literally billions of times greater than we use today. The lifetime of the sun is an estimated 4-5 billion years, making space solar power a truly long-term energy solution. As Earth receives only one part in 2.3 billion of the Sun's output, space solar power is by far the largest potential energy source available, dwarfing all others combined. Solar energy is routinely used on nearly all spacecraft today. This technology on a larger scale, combined with already demonstrated wireless power transmission (see 2-minute video of demo), can supply nearly all the electrical needs of our planet.

Another need is to move away from fossil fuels for our transportation system. While electricity powers few vehicles today, hybrids will soon evolve into plug-in hybrids which can use electric energy from the grid. As batteries, super-capacitors, and fuel cells improve, the gasoline engine will gradually play a smaller and smaller role in transportation — but only if we can generate the enormous quantities of electrical energy we need. It doesn't help to remove fossil fuels from vehicles if you just turn around and use fossil fuels again to generate the electricity to power those vehicles. Space solar power can provide the needed clean power for any future electric transportation system.

While all viable energy options should be pursued with vigor, space solar power has a number of substantial advantages over other energy sources.

http://www.nss.org/settlement/ssp/

[Beetwasher]

1. Wireless Transmission Is The Key

That tech is fucking amazing. I really think this could be a pretty doable solution to our energy issues.

[gordianot]

20. Correct n/t

[Statistical]

29. Transmission is already possible. Microwave.

Just make the rectenna large enough and the watt per sq foot is low. Low enough the beam is harmless.

Takes very big antennas (like 100m in space, and dozens of km on ground) but the rectenna is little more than a grid of wires supported by poles at 20' to 30 ' increments. It could be build over existing farmland for example.

Losses are very low compared to other methods of transmission at that distance.


Even more amazing is a panel is about 150% more efficient in space. Also on earth most places only have about 4 hours of sunglight (4 hours of peak sunlight equivalent), whereas in space is it 24. Combine those two elements and a panel in space produces roughly 9x as much power in one day as a panel on earth.

Another way to look at it is wordwide solar represents 2% of power production. If those same exact panels were instead in space they would produce 18% of worlds power supply.

[RC]

2. Pie-in-the-sky

How are they going to get all that energy down here without frying stuff on the ground?
Geosynchronous positions in orbit are only relative. They move around
And then there are clouds...

We can't even transmit energy on the ground with any efficiency. From space? Yeah right.

[berni_mccoy]

33. Actually, I saw a Discovery program just on this problem alone.

On a ground test, they are able to maintain a focused beam of microwave transmission energy through the thickest part of the atmosphere horizontally and maintain energy levels. They will certainly be able to do it from space.

[Statistical]

34. Microwave rectenna is about 85% efficient.

Tech his been around for about 40 years.
Well researched, well understood.

The goal is to make the rectennas very large so the watt per square inch is low enough to not be a danger.
Station keeping is trivial. We station keep thousands of sats and have been doing so for decades.

The major issue is lift costs. Not possible at $10K-$20K per kg.

However companies like SpaceX are working on reusable unmanned rockets.

http://en.wikipedia.org/wiki/Falcon_9

Cost to LEO would be about $3K. Then solar array could use an ion engine and move slowly (like months) to geo orbit. Then array would unfurl. The same ion engine could be use for station keeping.

[Johonny]

37. I think there is some worry

to atmospheric damage from space launches as well. Dramatic changes in launch rates make the relatively small impact from launch grow into a real and negative impact (depending on the propellants chosen).

The other problem associated with this is that it's unclear if such satellites would violate treaties on placing weapons into space. There is a fear such items could/would be weaponized.

[Statistical]

39. How? The output per square inch is less than sat TV signal.

By that logic DirecTV is a weapons platform. It has the ability to send aim-able beam of energy at around 20x the power density of this array.

atmospheric damage is an issue but I would hope that after the first few commercially viable systems (which would only take dozens of launches) there would be a race to build a space elevator.

The first nation with space elevator would have a huge and massively profitable monopoly on launches. Given the magnitude lower cost space elevator cost would be around $200 per kg compared to $10K - $20K per kg for rockets. The host nation could set prices far below what rocket launches could ever offer but still with a massive markup. Say $4K per kg (which would be a 2000% markup).

Most nations would likely pay the "massive markup" because it is both cheaper than rockets and also easier to pay $4K per kg than an upfront cost of $20B to build another space elevator. Any nation needing to launch less than 6 million kg a year into space would be better off paying the premium. This would create an artificial monopoly for likely decades.

[Johonny]

40. wait

You believe cost analysis studies of fictional space elevators?

[Statistical]

43. To an exact degree... no.

However science is always improving eventually we will have a space elevator. Will it be in 2050 or 2150? Not sure but it will happen.

The idea that from now till end of time man will use chemical rockets is about as laughable as saying till end of time man will never go from horse to mechanized transportation.

The one thing that would spur research into space elevator would be a large regular demand for launches (the launches you want to avoid for environmental damage and power companies want to avoid for the $10K/kg pricetag.

If one solar array is profitable then all solar arrays are profitable and that would generate a massive demand for launches. It could be stepping stone to a non chemical method off the planet. Maybe not a space elevator there are other concepts (launch loops, spaceplanes, skyhooks, etc).

Right now the need for launches (in terms of sheer tonnage launches) makes an elevator unpractical hence not much research. I am realistic it likely will not happen in my lifetime but my childrens lifetime or grandchildrens lifetime? Maybe.

[anigbrowl]

48. More like pie dish in the sky...

I understand your skepticism but this is actually a good long-term solution. It'll take several decades to implement though, it's not gonna happen overnight by any means.

[Ready4Change]

3. Something I've always wondered...

How do they plan to keep these in orbit?

Their whole purpose is to gather sunlight. And like a solar sail, that sunlight is going to effect their position and velocity. How are they going to maintain position/orbit? Are they going to carry reaction mass? Are they going to need to go off-line in order to change their angle and 'sail' back into place?

I mean I love the idea. Just wondering about the details.

[notesdev]

6. If they can solve the engineering problems

if they manage to solve the transmission problem, keeping the orbit correct should be fairly trivial - they'll be pumping through a ton of power, a tiny percentage of that could be diverted to onboard propulsion when required.

The real technical issues are getting it into space and building the receiving stations, we'll need some technology that we don't yet have. But this is one of the few genuine potential solutions to the energy crisis, unlike a lot of the fashionable "green" stuff we hear about (wind, terrestrial solar, tidal, bio, etc.).

[Beetwasher]

10. Yup

This very doable and within a relatively short time given the proper attention and investment.

[Ready4Change]

16. But we don't yet have an 'electric space drive.'

Even the recent ion drive, which uses a lot of power and is very efficient, still uses SOME reaction mass.

And the use of gyros for positioning relative to the sun only works for so long before they reach their RPM limits. At that point don't you need reaction motors to hold things in place while the gyros are slowed? (Although, now that I think of it, I suppose you could get clever and use sunlight pressure as a force to react against and slow the gyros that way. Hmmm.)

[jimlup]

7. Since the earth orbits the sun the relative perturbation on the panels

would not necessarily have a de-orbit preference. I haven't done the calculation but it wouldn't be that hard - my guess is that the effect is worth considering but not significant if accounted for.

[Canuckistanian]

9. It would have to be Geosynchronous orbit

So that it's always above the collection array. And they'd use pivoting solar panels or mirrors to collect the light.

[eppur_se_muova]

22. That can be put to good use -- in a "statite".

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

http://v3.espacenet.com/publicationDetails/biblio?CC=US&NR=5183225&KC=&FT=E

[Statistical]

32. An array would be far too dense for solar wind to be a factor.

Solar sails to have any meaningful acceleration would need to be a magntidue larger and a magnitude lighter.

Solar wind would produce a negligible amount of force on an object as dense as solar array. Even so some station keeping would be needed. Ion drive can produce about 50x as much thrust per unit of reaction mass and it just requires electrical power so would be a good combination for solar array.

[stevedeshazer]

4. I really believe this can be done.

Tesla was on to this a long time ago.

Recommended.

[1]

5. it would be possible with a really, really, really, really, really, really long extension cord...

[tridim]

12. Or a beam of microwave energy.

[wuushew]

8. Not economical

the cost to lift anything into orbit is tens of thousands of dollars per pound.

High risk, high capital requirements and long payback period disfavor such a scheme.

[Beetwasher]

11. Baloney

With the amount of energy this type of system could supply it would pay for itself in no time.

[wuushew]

14. Show me the math

[Beetwasher]

17. You First

You made the claim against the economics. Lets see yr data and I'll tell you what's wrong with it.

[tridim]

15. Space elevators aren't that far off either.

We could send them up by the thousands.

[and-justice-for-all]

24. The only thing we are waiting for on that, is the cable issue...

something to do with nanotechnology.

[RC]

27. Besides all the space junk, then we'd have all but invisible cables to avoid

And then if and when anything were to be sent up this cable and released at the top, the cable would then be a sling and propel the load off into the void.
Think not? Then what keep the counter weight up there?

[tridim]

28. The "center of mass" point on the cable would have no sling effect

It's the point where centrifugal force is canceled out by the Earth's gravity. That's where orbiting payloads would be released.

But, the sling effect at the counterweight would be desirable for craft that need velocity to travel outside beyond Earth's orbit. The counterweight is nothing more than a satellite orbiting the Earth.

The math is solid, but there are still lots of practical problems to be solved.

[Canuckistanian]

13. Quite right

Unless it's a multi-decade project involving many rocket launch sites. In order to make it work, it would have to be MASSIVE, like a kilometer long panel array.

No one country could afford to do it alone, it would require a multinational effort, like the ISS. This would have to be government administered and NOT depend on the vagaries of investors.

It would be like the largest public works project since the Panama Canal or the 3 Rivers Gorge.

[anarch]

18. people should really pay more attention to things like this

because this or something like it is going to have to happen eventually, or the human population is going to decline dramatically within the next thousand years or so (if not sooner)

[gordianot]

19. Tesla worked out the transmission equipment long before satellites.

Granted it was not on this scale. Westinghouse was not interested in wireless transmission of energy.

[eppur_se_muova]

21. Wouldn't it be cheaper to build it in the desert?

This idea has been around for decades now, and I still haven't seen a cost/benefit/RISK analysis that justifies putting these things in space.

If nothing else, repair and upgrades would be enormously simpler on the ground.

[comrade snarky]

25. Building in either location has it's problems

Huge desert arrays could damage desert ecosystems. That and the sun goes down so you average 12 useful hours a day and have an atmosphere scattering all that sweet sweet energy.

Repairs would be one heck of a lot harder in geosynchronous orbit but then again most of the things that would need repairing in the desert would last a lot longer in space. Out in orbit there's no sand, condensation, bugs or animals to muck things up.

I don't pretend to know the answers but I'm sure glad to see a pilot project is in the works.

[Statistical]

45. Worse still power output is dependent on peak sun (solar insolation) which is much lower.

Most locations have <4 hours of peak sun. Some of the best spots are in the 6-7 range and they tend to be the furthest away from people.


Solar panels are rated on output at peak sun.
So a 100watt solar panel in an area with solar insolation of 7 would produce 700wh or 0.7kwh.
The actual number of "daylight hours" doesn't matter.

Space is 24 hours and the sunlight there is 50% stronger.
100watt panel would produce 150watts * 24 hours = 3600wh = 3.6kwh.

Same panel roughly 9x as much power.

[Statistical]

35. Problem is people don't tend to live in desert.

NY needs a lot of power. It isn't in a good wind lane, has poor solar output, has no real hydro potential.
So how does NYC get energy. Mostly by burning coal.

The advantage of solar arrays is they could beam power anywhere (with about 85% efficiency). So NYC could build a ground station a couple miles into the suburbs. As more power is needed build more ground stations and launch more birds.

[Johonny]

41. people don't live in space either

so strawman there.

[Statistical]

44. But space is directly over every major city in the world

The distance from NYC to space is 26 miles.
The distance from NYC to any major solar park is a magnitude more.

If NYC was <26 miles from a desert then you would have a good point.

Putting power generation over the cities means power can be produced closer to where it is consumed.
We generally don't consider space "close" but to electricity straight up is no further away than horizontally.

[TCJ70]

23. What are the long term maintenance cost projections on one?

While this is an interesting direction to be going in, how long would it take for a maintenance crew to go up and fix one should something go awry? We should be investing money into other renewable sources to provide a set of renewable energy solutions: Earth-based solar, geothermal, water (wave and river current) and wind.

[Statistical]

46. I doubt at this stage maintenance is considered.

The cost to put crew in space is too expensive.

Rather the system would be designed redundant so output decays naturally overtime due to damage, and components wearing out.

Eventually when we have cheap access to space, a larger ISS, bunch of space tugs and dozens or hundreds of arrays like this maintenance crews living in space (maybe 3 months shift on a space tug/repair platform) would be possible.

This is first step, more a proof on concept than anything else.

[Ghost Dog]

26. Will the first such station be American? Japanese?

Chinese? European? Russian? ...

Competition... Or an international collaborative project?

Japan eyes solar station in space - http://www.chinadaily.com.cn/world/2009-11/09/content_8933756.htm
China, the US, and space solar power - http://www.thespacereview.com/article/985/1
European Space Agency Space Solar Power Studies - http://www.nss.org/settlement/ssp/library/esa.html
Space solar power station for Russia (pdf) - http://zhurnal.ape.relarn.ru/articles/2009/050e.pdf

The SBSP Study Group concluded that should the U.S. begin a coordinated national program to develop SBSP, it should expect to find that broad interest in SBSP exists outside of the US Government, ranging from aerospace and energy industries; to foreign governments such as Japan, the EU, Canada, India, China, Russia, and others; to many individual citizens who are increasingly concerned about the preservation of energy security and environmental quality. While the best chances for development are likely to occur with US Government support, it is entirely possible that SBSP development may be independently pursued elsewhere without U.S. leadership. - Space-Based Solar Power As an Opportunity for Strategic Security: http://www.nss.org/settlement/ssp/library/nsso.htm

[Phoonzang]

30. I've wanted this to happen for so long.

All the energy we'll ever need (well, for a few hundred years) is available in plentiful amounts in space. Actually if you mine asteroids, all the minerals we'll ever need are in space as well.

[Soylent Brice]

31. awesome. K&R

[Freddie Stubbs]

36. They could build a Dyson Sphere

[ProfessorGAC]

38. I Was Thinking the Very Same!

The very idea is so cool, i'll never forget it.
GAC

[leeroysphitz]

42. Beamed to the surface via microwaves to give us all cancer...

[Dr. Strange]

47. What the hell? We're going to steal the sun's energy?

Typical human hubris! First we destroyed the moon with that missile thing, and now we're going to take the sun's energy, as if it's ours to do with as we wish.

[Gold Metal Flake]

49. It's already happening...

http://latimesblogs.latimes.com/greenspace/2009/12/solar-power-in-space.html

California utilities push for solar, wind and carbon-capture projects
December 3, 2009 | 4:16 pm

California regulators went out of this world today and gave the go-ahead to a power-purchase agreement involving the nation’s first solar power plant in space.

Pacific Gas & Electric Co., the state’s largest utility, will proceed with a 15-year contract with Manhattan Beach start-up Solaren Corp., after receiving approval from the California Public Utilities Commission.

The project, which is expected to go live in 2016, will use solar cells from Solaren on orbiting satellites to convert energy from the sun into radio-frequency waves. The waves will be transmitted to a receiving station near Fresno and reverted back into electricity.

The project should produce 1,700 gigawatt-hours of energy each year, according to the commission. The Japanese government said this summer that it intends to pursue a similar space-based solar program.

[wuushew]

50. Solaren Corp is a scam

http://matter2energy.wordpress.com/2009/06/12/space-power/

[Statistical]

52. That guys math is a scam

About half dozen mistakes and assumptions.

1) "2000 hours of direct sunlight"? Ok that is utterly meaningless. Toronto has a solar insolation of 2.5 hours per day ~= 912 hours of PEAK sunlight per year vs 8760 per year in space

So a given panel in space is roughly (8760 * 1366 ) / (912 * 950) = 13x.

So solar panel is space is not 4x as powerful as one in Toronto it is 13x as powerful.
Even in most parts of CA with insolation of 5.5 it is roughly 6x as powerful.

Of course he also has the worst idea ever for solar array. The goal would be to use lightweight mirrors to concentrate solar energy 300%-500% onto a smaller solar panel.

Rather than a massive array of heavy panels the goal would be to reduce the cost by using a smaller amount of heavy ultra efficient (which are too expensive for use on earth) panels and a much larger array of mirrors to focus light on them.

Also the launch weights are weight out of line. Current large volume heavy lift is about $12K per KG not per pound (an error rate of 250%). Programs like Falcon9 are attempting to get that down to $3K per KG.

All put together that makes his estimate off by a factor 10x. Also the goal for a prototype is simply to prove it can be done. More efficient designs and launches will follow.

[Lorien]

51. I hope it works and the transmission doesn't have any nasty side effects

personally I'd still like to have super energy efficient solar panels on my home so I could be off the grid completely. I just don't like relying on utility companies-especially after a hurricane. Almost anything that gets us off fossil fuels is a good thing. The next step; getting off meat, which contributes more to climate change than cars do!