Solar Energy from Space

[ygolo]

Collecting solar energy in space


Space Future - A Fresh Look at Space Solar Power: New Architectures, Concepts and Technologies


Are our collective modern imaginations too feeble to attempt something like this?
I suppose Sci. Fi. has ruined this too. Are you thinking death-rays and the like?

What happened to the days when mankind dreamed of a better day and did their best to make it happen?

Look at past revolutionary jumps forward, both a great improvement in information technology (written language, printing press) and energy technology (farming instead of hunting-gathering, steam engine) are needed to move society to a new era. WE have a lot of new information technology but we have a crisis in energy.

Any thoughts?

[Apollonian]

From my experience at NASA and as an engineer in general, my understanding is that people are working on this stuff. The trouble is that budgeting concerns understandably slow things down. Many of the previous leeps in technology came at times when there was large spending for research and development either from governmental or private resources.

Also, I think that in the near future we will start to see countries like China and India catch up into the space age. It will be interesting to see what role they play.

As for the solar energy from space idea, there is a LOT of work left to be done on this. The problem is how to create an energy transfer system which will remain efficient when transmitting through the atmosphere and creating a ground-based power system which can successfully convert the beam energy into electrical power. We currently don't have the component technology to put such a system together, so it remains pure R&D work, not that it isn't possible. It just takes time.

I think one of the more promising technologies for the near term lies in advances in fuel cells and the use of hydrogen electrolysis. Storing energy more efficiently can do much to elieviate energy concerns.

Improving automotive technologies is probably the most practical. Hybrid technology is beginning to mature, and there are other ideas coming down the pipe. However, what most people don't realize is that there is an often long engineering cycle which needs to occur between the development of the original design concept and its practical implementation. Once the science is proven, the engineering process needs to take the science and create an efficient device which can utilize the principles. And then there are budgeting politics and profit motives, of course.

On a side note, the interesting thing about today's space program is that we are learning to build better spacecraft on a smaller budget. It would be great if NASA could have more than 1.7% (last I heard) of the national budget. However, this way it makes people think about how to do things well without running up the cost like in the Apollo or Shuttle programs.

[Lateralus]

Originally Posted by Apollonian

As for the solar energy from space idea, there is a LOT of work left to be done on this. The problem is how to create an energy transfer system which will remain efficient when transmitting through the atmosphere and creating a ground-based power system which can successfully convert the beam energy into electrical power. We currently don't have the component technology to put such a system together, so it remains pure R&D work, not that it isn't possible. It just takes time.

Perhaps Soundwave could help?

[ptgatsby]

I've never understood the appeal of the whole energy transfer from space thing. What's the appeal?

First we gotta build the whole thing. Then get it up. Then protect it from all the spacey stuff floating around (it's not exactly "small"). Then we gotta maintain it. Then we need a ground station. We need a transmission system (nothing like beaming MWs of energy in any form of radiation onto a small part of the ground...). Then we need the whole transmission and conversion stuff - twice.

This is one of the few things that I just think is sci-fi. The only advantage I can think of is solar energy 24 hours a day beamed to different parts of the world. But you are halving the already low efficiency of power (I'm assuming that the efficiency of solar cells, while prohibitively expensive, is nearly 50%)... Without even doing the math, to generate even close to the power of a modern nuclear plant, you are looking at a giantic array of cells. Assuming that I am correct that it'd generate roughly 250W net/sq meter or assuming ground station matches the size of the array, 2sq meters, and it'd need to generate in excess of 50 MWe to be on a similar scope as a modern power plant...

I'm not against the research being done into solar power, but I think this is many many steps removed from being practical. I don't really see the appeal behind this... it seems like the beamed energy will still need a rather large foot print and is still subject to considerable loss.

Am I overlooking some huge advantages to offset the hurdles that we currently face? Does it not make more sense to focus on the technical problems in micro rather than as a whole (ie: solar power, space travel, transmission)?

[ygolo]

Originally Posted by Apollonian

Also, I think that in the near future we will start to see countries like China and India catch up into the space age. It will be interesting to see what role they play.

I think this one needs to be an international effort. If any one country get there completely by themselves, it would certainly become a superpower and a target. The U.S. already has that role, but seems a bit fickle these days when it comes to target process in science and tech. Myane would be scientist and engineer, are choosing to stay in their respective countries rather than immigrate to the U.S. because of this. An international effort towards a program (probably half a century away, at least) will share the burdens and the benefits. An the U.S. will have to deal with thier lost super-power status due to its lack of collective magination.

Originally Posted by Apollonian

As for the solar energy from space idea, there is a LOT of work left to be done on this. The problem is how to create an energy transfer system which will remain efficient when transmitting through the atmosphere and creating a ground-based power system which can successfully convert the beam energy into electrical power. We currently don't have the component technology to put such a system together, so it remains pure R&D work, not that it isn't possible. It just takes time.

I've heard people say this will make NASA's mission to go to the moon look like a college science project. Yes there is a lot of work, and I don't think it would be a good idea for it to be gov't run.

Originally Posted by Apollonian

I think one of the more promising technologies for the near term lies in advances in fuel cells and the use of hydrogen electrolysis. Storing energy more efficiently can do much to elieviate energy concerns.

Improving automotive technologies is probably the most practical. Hybrid technology is beginning to mature, and there are other ideas coming down the pipe. However, what most people don't realize is that there is an often long engineering cycle which needs to occur between the development of the original design concept and its practical implementation. Once the science is proven, the engineering process needs to take the science and create an efficient device which can utilize the principles. And then there are budgeting politics and profit motives, of course.

Yes. Better engine technology is a good thing, but this would be a near permanent source of energy nearly free of fossil fuel once done.

Originally Posted by Apollonian

On a side note, the interesting thing about today's space program is that we are learning to build better spacecraft on a smaller budget. It would be great if NASA could have more than 1.7% (last I heard) of the national budget. However, this way it makes people think about how to do things well without running up the cost like in the Apollo or Shuttle programs.

I don't trust the gov't to handle a project this size anymore. But I think they can do a good job of spurring research in the private sector.

Originally Posted by ptgatsby

I've never understood the appeal of the whole energy transfer from space thing. What's the appeal?

First we gotta build the whole thing. Then get it up. Then protect it from all the spacey stuff floating around (it's not exactly "small"). Then we gotta maintain it. Then we need a ground station. We need a transmission system (nothing like beaming MWs of energy in any form of radiation onto a small part of the ground...). Then we need the whole transmission and conversion stuff - twice.

This is part of the reason I think Sci. Fi. generates cynicism about Sci. Real. It is hard to get specifics on a program that is this long term, this early in the program. We are talking about (im)possibilities here and we need to be careful when saying things like "it is cost prohibitive" or "the risks out-weigh the benefits" based of specifics (because the specifics can and will change).

Yes, based on current solar panel technology and microwave power transmission this seems ill-conceived. But we've barely scratched the surface in these areas because there hasn't been much economic incentive.

Originally Posted by ptgatsby

This is one of the few things that I just think is sci-fi. The only advantage I can think of is solar energy 24 hours a day beamed to different parts of the world. But you are halving the already low efficiency of power (I'm assuming that the efficiency of solar cells, while prohibitively expensive, is nearly 50%)... Without even doing the math, to generate even close to the power of a modern nuclear plant, you are looking at a giantic array of cells. Assuming that I am correct that it'd generate roughly 250W net/sq meter or assuming ground station matches the size of the array, 2sq meters, and it'd need to generate in excess of 50 MWe to be on a similar scope as a modern power plant...

There are a lot of assumptions embedded in this analysis. Regarding the biggest assumption: there is no need for it to be one giant solar array (in-fact, that seems to be the most impractical choice), but the system can be launched like the GPS satelites, with many smaller solar collectors and power transmitters, creating a network in space (which would work in a fault tolerant manner due to space junk etc.)

Originally Posted by ptgatsby

I'm not against the research being done into solar power, but I think this is many many steps removed from being practical. I don't really see the appeal behind this... it seems like the beamed energy will still need a rather large foot print and is still subject to considerable loss.

Yes. This is very long term, and there is a lot of work. Again, you have this sci-fi. conception of the technology that makes it seem impractical. It will once again likely be many smaller power receiving stations placed around the globe (again similar to the second level used in GPS).

Solar cell efficiency remains low, partly because too few of the potential technologies have been explored, due to lack of funding. If we look at the amount that private industry spends to keep Moore's Law alive in the semiconductor industry (and there is always some quoted impossibility by naysayers) and the clever tricks researchers have come-up with, one gets a sense that the exponential savings is really a measure of the human ability to overcome technical challenges given enough funding. IOW, Moore's law is an economic challenge, not a physical law. If we pose the same challenge to solar panel community and come up with an incentive for private firms to establish their own cheaper energy network, that may be enough. Again, this early, it is about exploring possibilities not declaring impossibilities based on some pre-conceived notions.

Originally Posted by ptgatsby

Am I overlooking some huge advantages to offset the hurdles that we currently face? Does it not make more sense to focus on the technical problems in micro rather than as a whole (ie: solar power, space travel, transmission)?

The appeal is to have a global power system that is not based on fossil fuels. The main advantage is far less reliance on fossil fuels around the globe. But the idea is for gov'ts around the globe to spur research in this area so that this method becomes more popular than the fossil fuel methods.

They can also help with patching the new system into the power grid, or create a few seed grants or low interest loans for ventures aiming to make money in this area, etc.

[Lateralus]

Would these systems use energy that would already be absorbed by the Earth? Or would they gather energy that would pass by, without intervention?

[ptgatsby]

Originally Posted by ygolo

Yes, based on current solar panel technology and microwave power transmission this seems ill-conceived. But we've barely scratched the surface in these areas because there hasn't been much economic incentive.

I disagree - there has been a ton of research in this area. We are up to 50% efficiency in solar panels... for some reason the problem is always "not enough economic incentive"... The reason there is no economic incentive is because... there is no economic incentive! Those kinds of solar panels cost an absolute fortune, so it makes sense to have efficiency in the 10-15% range at a fraction of the cost, even though you need many more of them.

The problem is that they aren't efficient, that they are expensive... that there are much better alternatives. Isn't that the point? Research into solar panels is important, very important. That's where I want to see my money going (fortunately, this is normally the case.)

There are a lot of assumptions embedded in this analysis. Regarding the biggest assumption: there is no need for it to be one giant solar array (in-fact, that seems to be the most impractical choice), but the system can be launched like the GPS satelites, with many smaller solar collectors and power transmitters, creating a network in space (which would work in a fault tolerant manner due to space junk etc.)

A hundred arrays at 2000 sq meters is more expensive, not less, than one 200,000 array.

Even if there was some lost economy, the point stands - the shear scope of what would have to be done to create one equivalent power station on earth puts it out of reach.

Yes. This is very long term, and there is a lot of work. Again, you have this sci-fi. conception of the technology that makes it seem impractical. It will once again likely be many smaller power receiving stations placed around the globe (again similar to the second level used in GPS).

You'll have to explain to me how saying that research into conceptual systems with multiple current practical oversights is a waste has a root bias of a "sci-fi" view of science (when this really has nothing to do with science and everything to do with engineering).

The research should be science - it should be into space exploration, solar panels, material research, etc. The components of the system will make it possible. And when it becomes even remotely feasible, the research into development can be undertaken.

At this point, I'd put conceptual space elevator research ahead of any form of space beaming (other ramifications aside).

As far as I can see, the concept of beaming power from space is "Sci-fi" minded. We take what we can do, we look at it, see it isn't possible... and then, what... throw money at it until it is possible? If ever? The concept is what is appealing, not the feasibility, and that makes viewing these kinds of projects as "sci-fi" a risk. The risk that because we think of it, it suddenly becomes possible. The realisation of the dream overtakes the reality of the project.

I'd say this is at the "pre-feasibility" phase. Research into viability is what should be done. It's not, therefore the goal should be to spend any further research into other alternatives, and it should be revisited in the future when the assumptions made have changed.

Solar cell efficiency remains low, partly because too few of the potential technologies have been explored, due to lack of funding. If we look at the amount that private industry spends to keep Moore's Law alive in the semiconductor industry (and there is always some quoted impossibility by naysayers) and the clever tricks researchers have come-up with, one gets a sense that the exponential savings is really a measure of the human ability to overcome technical challenges given enough funding. IOW, Moore's law is an economic challenge, not a physical law. If we pose the same challenge to solar panel community and come up with an incentive for private firms to establish their own cheaper energy network, that may be enough. Again, this early, it is about exploring possibilities not declaring impossibilities based on some pre-conceived notions.

Use 100% efficiency and measure the size of the array. 1000w/sq meter, I believe, at peak season/etc. 70 MWe is the current 100-million dollar nuclear powerplant. Reduce the cost of sending stuff up by an order of magnitude, even.

Feasibility goes way up as we are able to build it closer to the sun... that's about the only major difference I can see.

(Again, the argument here has nothing to do with space and solar power, only the space beaming as an actual project being attempted. I'm all for research into the components, but not into the system as a whole.)

[ygolo]

Originally Posted by ptgatsby

I disagree - there has been a ton of research in this area. We are up to 50% efficiency in solar panels... for some reason the problem is always "not enough economic incentive"... The reason there is no economic incentive is because... there is no economic incentive! Those kinds of solar panels cost an absolute fortune, so it makes sense to have efficiency in the 10-15% range at a fraction of the cost, even though you need many more of them.

The problem is that they aren't efficient, that they are expensive... that there are much better alternatives. Isn't that the point? Research into solar panels is important, very important. That's where I want to see my money going (fortunately, this is normally the case.)

I agree with you on this. So have most professors I've heard give lectures on solar power. Research on cheaper solar panels would be the type of improvements I meant. We certainly cannot ignore the economic aspects of this project.

Originally Posted by ptgatsby

A hundred arrays at 2000 sq meters is more expensive, not less, than one 200,000 array.

This also seem incredibly assumption loaded (Have you already designed the system in your head, decided it is the only way and made the cost estimate based on that?). Yes, the manufacture of one solar panel will cost more than the manufacture of many, generally speaking (though at the scales we're talking about, even that is probably not true. There are reasons why silicon wafers aren't giant, you know.)

A networked solution also allows for the possibility of more flexibility in collecting the solar energy, and sending it to particular patches into particular places in the power grid.

The cost of protecting a network is also likely to be reduced (we have to consider the time-value, and risk-avoidance value of money too). Very few engineering projects are successful when done with a mind-set of making big components, and incorporating them into a big system later on. There are too many things that can go wrong. Having a smaller scale system done as a proof-of concept allows for great amounts of risk-reduction (which has monetary value, if I am not mistaken).

One more reason is that launching of smaller payloads into space and patching in the energy generated from it would allow for the project to start paying a little it's own cost back.

It is the same reasoning as getting a loan. You may end-up paying more in the long run, but it makes it possible to get started (and you are betting that you will eventually cross break even).

Originally Posted by ptgatsby

Even if there was some lost economy, the point stands - the shear scope of what would have to be done to create one equivalent power station on earth puts it out of reach.



You'll have to explain to me how saying that research into conceptual systems with multiple current practical oversights is a waste has a root bias of a "sci-fi" view of science (when this really has nothing to do with science and everything to do with engineering).

That is a bit off topic and can be discussed later.

Originally Posted by ptgatsby

The research should be science - it should be into space exploration, solar panels, material research, etc. The components of the system will make it possible. And when it becomes even remotely feasible, the research into development can be undertaken.

This is the basic fallacy I was pointing out to begin with. The feasibility of the system depends on the system you are talking about. No engineering system is allowed by the components themselves.

Do your analysis on cell-phone and GPS research the same way you did for this, and see if you come up with them being feasible at the time. System and component research have to go on in parallel, because components don't magically create a system. If you want your ROI for component research, you need a system for the components to plug into.

Originally Posted by ptgatsby

At this point, I'd put conceptual space elevator research ahead of any form of space beaming (other ramifications aside).

As far as I can see, the concept of beaming power from space is "Sci-fi" minded. We take what we can do, we look at it, see it isn't possible... and then, what... throw money at it until it is possible? If ever? The concept is what is appealing, not the feasibility, and that makes viewing these kinds of projects as "sci-fi" a risk. The risk that because we think of it, it suddenly becomes possible. The realisation of the dream overtakes the reality of the project.

I'd say this is at the "pre-feasibility" phase. Research into viability is what should be done. It's not, therefore the goal should be to spend any further research into other alternatives, and it should be revisited in the future when the assumptions made have changed.



Use 100% efficiency and measure the size of the array. 1000w/sq meter, I believe, at peak season/etc. 70 MWe is the current 100-million dollar nuclear powerplant. Reduce the cost of sending stuff up by an order of magnitude, even.

Feasibility goes way up as we are able to build it closer to the sun... that's about the only major difference I can see.

(Again, the argument here has nothing to do with space and solar power, only the space beaming as an actual project being attempted. I'm all for research into the components, but not into the system as a whole.)

Who says we have to replace current coal or Nuclear power plants?

Keep in mind that public relations also plays a part in economic decisions.

Did you read the second link in the OP? I am wondering where you are getting your numbers.

Besides, we can do experiments and revisions of power transmission through atmosphere without going into space. Ans rethinking the system has a lot of advantages in the way the system can be financed, and "monitized".

The gov't give "future carbon credits" to companies that aim to implement parts of this sort of system (perhaps even maintain partial rights to carbon credits of future users, etc.)

Rethinking the way systems are implemented may yield an form that requires far less from the components (perhaps repeated power transmission stations, at several levels in the atmosphere, etc.) We should not dismiss system research due our over-simplistic view of a system that view as unfeasible. (In fact, I would say this is all the more reason to think in terms of systems) This is an engineering project, not a science project. We ought not wait for our 'anti-gravity' module to proceed with conceiving of different system implementations and trying to make that as cheap as possible.

[Dark Razor]

Originally Posted by ygolo

Look at past revolutionary jumps forward, both a great improvement in information technology (written language, printing press) and energy technology (farming instead of hunting-gathering, steam engine) are needed to move society to a new era. WE have a lot of new information technology but we have a crisis in energy.

Any thoughts?

Its because most humans are more interested in the iPhone and the Playstation 3 than in something like, say.. not becoming extinct within the next 100 years.

That's why we allocate far more ressources inot the development of ever more sophisticated useless crap instead of something like alternative energy, so basically its because people prefer watching retarded youtube clips on a 2 inch screen to the survival of their own species, it makes you wonder how the human race ever evolved past the stone age.

[ygolo]

Originally Posted by Lateralus

Would these systems use energy that would already be absorbed by the Earth? Or would they gather energy that would pass by, without intervention?

It depends. I don't think you have to worry about it blocking out the sun, etc. though.