Space Solar Power for the Obama nation?

icarus · Post by **icarus** » Sun Dec 21, 2008 9:07 pm

http://www.scribd.com/doc/8736849/Space ... ate-Change

Interesting bit about funding to same level as fusion research ($300 million per annum) total $21 billion spent so far. Also says no breakthrough physics or engineering necessary ... cloud cuckoo has invaded Washington?

Skipjack · Post by **Skipjack** » Sun Dec 21, 2008 10:08 pm

While I am personally getting excited about pretty much anything that is related to space stuff (particularily RLVs and interplanetary spaceships, which is what brought me here in the first place), I personally think that Space based solar power is bogus^10.
As long as we do not have any means of getting stuff into orbit for a reasonable price it is totally uncompetitive, even in theory (you can build a few nuclear powerplants for the same price as one SBSP station.
Now if we assumed that for some miracle (I am always hoping) someone builds some relyable and cheap RLVs to get stuff into space, there are still quite a few issues to overcome and no, I am not going to list all of them here since that would take to long. It is enough that they are already going to fail at the first step: Getting that stuff into space in the first place!

MirariNefas · Post by **MirariNefas** » Sun Dec 21, 2008 10:51 pm

There are many ways to make getting things into space cheaper. Magnetic launch assist tracks, space fountain, etc. These things require very large development costs and get cheaper per kg the more launches you make, so if you wanted to do something like replace half our power with sbsp, it would be economical. But if they're just talking about a few test satellites to power lightbulbs every year, it won't be worth so much.

On the other hand, thin film solar tech is decreasing the mass/watt issue, so maybe a decent Ares IV filled with a giant roll of thin film could make something close to economical. Maybe some next generation thin film and neoAres IV could actually make it competitive in some future decade.

I'd like to know if anyone can figure out how much mass we'd have to add to the moonbase to get some solar cell manufacture going out there. If the moon can refuel rockets and build solar cells, that might also work, considering we're building a base anyway.

Professor Science · Post by **Professor Science** » Sun Dec 21, 2008 11:03 pm

i think SPS are totally feasible, if you aren't using terestial materials. I've got a better idea though.

Ship up a robot to the moon, have it process lunar silicon into solar panels and hook them up to a microwave laser non stop till you've cover like half the moon in them. then have land side rectannaes recieve all the power you want.

Skipjack · Post by **Skipjack** » Sun Dec 21, 2008 11:45 pm

Unless you are talking about a launch vehicle that I have yet to hear off, then this should called AresV not Ares IV.
Ares V is part of the VSE- architecture proposed by NASA.
Ares V is a heavy lift vehicle and it can lift a lot of mass into GEO or LEO and even quite some substancial mass to a lunar orbit.
However, it does not do that for cheap. In fact it is actually quite expensive. A much cheaper alternative would be Falcon9 and Falcon 9 heavy.
All 3 of them have something in common with all the other solutions named in this thread so far:
They do not exist (yet)!
Falcon 9 will at least fly next year (if they are lucky it will even make it into orbit). AresV wont be flying for another 7 years or so (not entirely sure right now) and all the other things dont even exist yet a peer reviewed design.
Until that is the case you would have to use either Russian LVs or the Ariane 5 to get stuff into orbit. Both are expensive also (the Russians are still cheaper than AresV though, I think).
It does not really matter how cheap the solar arrays are. They might even be the smallest part of the total weight. You would also need a support structure, dishes, control units, reaction control engines and little motors to rotate the dishes and the panels towards the sun or the receiver. All that is a lot of weight.
Let me quote Guiliano Barretta of Eutelsat here:
The cost increase for a launch “is frightening, you would faint,” [...]“There is a problem of access to space.”
( http://www.bloomberg.com/apps/news?pid= ... er=germany )

Now lets assume you can get the stuff into space, then we still have the problems of losses when transmitting the energy back to earth, we have the (though disputable) danger of this actually doing some damage to people or environments in the vicinity. Even if people only think that it could be dangerous it will make the whole thing mor expensive.
Hey, I mean there are people (even serious scientists) that say that cell phones are dangerous...
Anyway assuming you have managed to overcome all this, it still has to be cheaper and more cost effective than a fission plant on the ground, or you win nothing.

Now there are quite a few of people here on this board that think that fusion will never be cost efficient and also doubt the cost efficiency of fission and then some people really think that SBSP will ever be?
More frightening is the prospect that they might actually get funding that Fusion and new Fission systems could need.
Really, I am a space enthusiast and usually I would be "the more the merrier", but until someone actually builds an RLV that brings stuff into GEO for cheap, I am totally not convinced.

MirariNefas · Post by **MirariNefas** » Mon Dec 22, 2008 12:54 am

Skipjack wrote:Unless you are talking about a launch vehicle that I have yet to hear off, then this should called AresV not Ares IV.

Okay, the Ares V then. The Ares IV will never be built anyway. But I'm surprised, as an apparent space enthusiast, that you've never heard of it. It as a design configuration considered by NASA, and pushed in one form or another by DIRECT. They think it would be cheaper.

Skipjack wrote:Ares V is part of the VSE- architecture proposed by NASA.
Ares V is a heavy lift vehicle and it can lift a lot of mass into GEO or LEO and even quite some substancial mass to a lunar orbit.
However, it does not do that for cheap. In fact it is actually quite expensive. A much cheaper alternative would be Falcon9 and Falcon 9 heavy.

If the Falcons ever fly for the costs they advertise. All I've seen is a lightweight Falcon I with a to-date success rate of 25%. In any case, the Ares V is supposed to be cheaper than a shuttle to launch, but it'll hold about 6 times as much (edit: wikipedia now shows it will hold about 7.7 times as much, so I guess the payload estimates have been revised upward). That gets us some decent cost per kilogram figures, and a lot of those costs depend on the number of launches being made (more = cheaper).

If the US decides to go ahead and build the Ares V, it is the better bet by far. Considering we're talking about the Obama administration considering SBSP, the logical conclusion would be that if the administration decides it wants this, it will decide to get the launch mechanisms to make it so - at a minimum this means the Ares V.

Skipjack wrote:It does not really matter how cheap the solar arrays are. They might even be the smallest part of the total weight. You would also need a support structure, dishes, control units, reaction control engines and little motors to rotate the dishes and the panels towards the sun or the receiver. All that is a lot of weight.

I'm well aware of how much more it takes than the solar cells. But it does matter how massive they are (note, it doesn't matter how cheap they are). We can only hope they would be the lowest part of the total weight. That's a good target to shoot for.

Skipjack wrote:Now lets assume you can get the stuff into space, then we still have the problems of losses when transmitting the energy back to earth, we have the (though disputable) danger of this actually doing some damage to people or environments in the vicinity.

Losses should be about 10% or less with a suitable microwave system, which you'd know if you'd done your homework. The prospect of environmental or human damage is bunk, and less likely by looking at the physics than any cell phone damage. People may indeed be scared, but that's the only actual objection here. So build the first rectenna stations away from residential zones.

Skipjack wrote:Anyway assuming you have managed to overcome all this, it still has to be cheaper and more cost effective than a fission plant on the ground, or you win nothing.

You win proliferation resistance. You win a technology that the US would be an industry leader and exporter in. You win the chance to circumvent another fifty years of billion dollar arguments being made for another Yucca Mountain. Look, I like fission too, but a large cheap fission economy isn't exactly a done deal. And giving the entire world easy access to technology that could be used for breeding weapons grade fissionables makes me uneasy.

Skipjack wrote:Really, I am a space enthusiast and usually I would be "the more the merrier", but until someone actually builds an RLV that brings stuff into GEO for cheap, I am totally not convinced.

You don't exactly sound like a space enthusiast. If you were, you'd push for that RLV, and when it's built, space based solar power would very naturally become cheap. Any push for space based solar power would very naturally also be a push for cheaper access to space. So I seem to be missing something in your viewpoint here. Or do you think that cheaper access to space isn't actually possible?

Skipjack · Post by **Skipjack** » Mon Dec 22, 2008 1:36 am

But I'm surprised you've never heard of it. It as a design configuration considered by NASA, and pushed in one form or another by DIRECT. They think it would be cheaper.

No, the DIRECT guys designed the Jupiter and its derivates, which is a very different vehicle to the AresIV, which as you said will never be build (I therefore did not think that you were actually talking about it).
I generally dont pay much attention to vehicles that will never be built and this vehicle did not make it past preliminary design review. I am an enthusiast, but not that much of an enthusiast.
Robert Zubrins Mars Direct was to use a LV also called Ares, but just Ares. Maybe you are confusing something here.

If the Falcons ever fly for the costs they advertise. All I've seen is a lightweight Falcon I with a to-date success rate of 25%.

Well, they did manage to get Falcon 1 into orbit and Falcon 9 is on its way to the Cape right now. I am carefully sceptical and I doubt that their first flight will be a success, but it might.

If the US decides to go ahead and build the Ares V, it is the better bet by far.

More is not automatically cheaper, sorry. So far nothing NASA has ever done has ever been cheap. None of their LVs ever were competitive either. I would not put any hopes into AresV, which is still nothing but a sheet of paper, to be any cheaper than a flight on the Ariane5 (which at least exists).

You don't exactly sound like a space enthusiast.

Ahahaha, ROFL.

If you were, you'd push for that RLV

What RLV?
Right now noone is building any RLVs! The only RLVs currently being developed are for suborbital launches (Lynx, SpaceShip2, Goddard, Michelle B, etc).
The AresV is not an RLV! it is a ELV with maybe the boosters being refurbished (thats not even fully reused).
The Falcon first and second stages might at some point in the future, (provided SpaceX manages to get everything flying as they promise) be partially reusable (and/or refurbishable).
Other than this there are no RLVs anywhere to see. If you see any, please point me into the right direction. Because I would really like to see some some day. Thats one reason why I am in this forum. A polywell could be used for propulsion of an RLV. But if we had a working BFR, we would not need SBSP anymore.

Seriously, I do understand that lifting a lot of stuff into space for SBSP, would be a real nice boost for the launch vehicle industry, but I would rather see that money spent on the development of RLV- technology.
Once we have RLVs and cheap access to space, then we can revisit the SBSP ideas and maybe build such a thing. Until then, the money is IMHO better spent on Polywell and other Fusion reactor concepts.

MirariNefas · Post by **MirariNefas** » Mon Dec 22, 2008 2:12 am

No, the DIRECT guys designed the Jupiter and its derivates, which is a very different vehicle to the AresIV, which as you said will never be build (I therefore did not think that you were actually talking about it).
I generally dont pay much attention to vehicles that will never be built and this vehicle did not make it past preliminary design review. I am an enthusiast, but not that much of an enthusiast.
Robert Zubrins Mars Direct was to use a LV also called Ares, but just Ares. Maybe you are confusing something here.

Perhaps so. I stand corrected.

More is not automatically cheaper, sorry. So far nothing NASA has ever done has ever been cheap.

Oh I know, but more launches usually does mean cheaper. And even the Falcon line is embracing the idea that a bigger craft can heft payload to orbit more cheaply than a small one. I say that the Ares V is a better bet than the Falcon merely because the Falcon 9 will probably never make orbit, while an Ares V actually will. NASA tends to be expensive, but at least they actually deliver. There've been a lot of failure space startups out there. SpaceX will probably give up their grand dreams and launch tiny rockets for five times what they originally promised.

What RLV?

A hypothetical one. Take your pick of proposed and partially studied designs.

The AresV is not an RLV!

Yeah, no shite sherlock.

If you see any, please point me into the right direction.

If you want proposals, sure. If you want one actually being built... well that's like asking me to point you to the solar power satellite under development. There aren't any... yet. Whether we should build some is what this thread is about.

Once we have RLVs and cheap access to space, then we can revisit the SBSP ideas and maybe build such a thing.

I just think that we need a good reason to motivate us to build the RLVs in the first place. Something of great strategic importance, like renewable energy, qualifies. There are a few other ways besides RLV's, like I pointed out in my first post, but cheaper access to space is definately the most sure way to make this work.

MirariNefas · Post by **MirariNefas** » Mon Dec 22, 2008 2:26 am

Actually, why are we arguing about the Ares V and Falcon 9's anyway? Whatever the case, my point is merely that with extremely light materials, economies of scale in launch, and or lunar materials, SBSP may barely be economical even without a radically improved launch design, and we both know that there are much better forms of launch out there than either rocket.

Skipjack · Post by **Skipjack** » Mon Dec 22, 2008 2:56 am

because the Falcon 9 will probably never make orbit

And you get your premunitions exactly from where? I would not dare to predict anything like that. I think that Elon is quite persistent and even if the first 3 launches of Falcon 9 fail, he will go for a fourth, like he did with Falcon1. Now, I am still not convinced they will make it, but I give Falcon9 a higher probability than Ares1 (Ares1 not AresV, AresV so far has less problems). NASA has has a history of less failed launches but more cancelled LV programmes instead. DCX, X33, etc.

Yeah, no shite sherlock.

Keep digging Watson!

If you want proposals, sure.

Proposals, I have got plenty myself, thanks. Yet they are not so forthcoming, havent been in the 30 years that I have been waiting for one to come up. Seen them all, starting with Phoenix, the first shuttle designs, HOTOL, the beloved DC-X (still wished someone picked that up and ran with it), the ill faited X33, the almost comical Rotary Rocket Roton, the Skylon, the Rocketplane Kistler designs (not even that reusable, but you take what you get) and then there were many in between those. Most of them never made it past the paper study.

My point is simply that we should spend the money on economical space launch first, before we spend it on SBSP. SBSP needs this in order to get of the ground literally...
Yes SBSP might be a good reason for building RLVs, but there are plenty of other reasons, many, many.
In any case SBSP, does not make sense BEFORE, we have a good space transport system. After that, we can try (and please forgive me, but I will still be skeptical then). Before that, it is a nice and (seeing those numbers) expensive paper study, that wont get anywhere.

Professor Science · Post by **Professor Science** » Mon Dec 22, 2008 3:51 am

really though, short of positive energy from regular proton-proton fusion, we'll eventually have to switch our power supply over to solar. it can't hurt to get some experience now.

KitemanSA · Post by **KitemanSA** » Mon Dec 22, 2008 6:16 pm

A combination of KITE launcher and HASTOL might actually grow into a truly cheap method of access. Inexpensive to begin with, easy to grow.

gblaze42 · Post by **gblaze42** » Mon Dec 22, 2008 6:41 pm

Skipjack wrote:
HOTOL, the beloved DC-X (still wished someone picked that up and ran with it)

Blue Origin did, their prototype 'Goddard' rocket is based on the DC-X design.

Skipjack · Post by **Skipjack** » Mon Dec 22, 2008 6:47 pm

I have heard about the KITE launch- idea before. Somehow noone built it yet though.
There is a company called JP Aerospace that is working on giant (!) airships as a launch platform (with suborbital bases and whatnot). They are making progress with that, though very slowly.
So far they "only" got to 30km hight. They will have to get a lot higher though (46 km) for their suborbital base and then they will still have to go to orbit from there (with a more than a mile long airship)...
Still, they are at least building and flying hardware. This is something that cant be said for many right now. Even NASAs Ares1 is still nothing but a paper plane. Ares1-X does not count for me, since it has very little in comon with the final Ares1 which has not even passed preliminary design review yet.

KitemanSA · Post by **KitemanSA** » Mon Dec 22, 2008 6:51 pm

Skipjack wrote:I have heard about the KITE launch- idea before. Somehow noone built it yet though.

That is because the originator is a government drudge and hasn't found anyone interested in pursuing it. There had been limited discussions with Tethers Unlimited (the HASTOL) folk, but other activities got in the way.