Space Solar Power

[Aero]

Quoting article by Alan Boyle - The first contract for space based solar power inked in California.
http://www.msnbc.msn.com/id/30198977
Shouldn't we be worried about Global Chilling?

[djolds1]

Quoting article by Alan Boyle - The first contract for space based solar power inked in California.
http://www.msnbc.msn.com/id/30198977

Kewlness!

Shouldn't we be worried about Global Chilling?

Yes, but what does that have to do with an SPS?

1.2-4.8 GW per sat, according to slide 6 of the interactive...

Laser Ablative launchers begin to attract...

Duane

[kurt9]

Theres only the little matter of developing the heavy-lift launch vehicles to put Solaren's SPS's into orbit. A minor detail.

[djolds1]

Theres only the little matter of developing the heavy-lift launch vehicles to put Solaren's SPS's into orbit. A minor detail.

Falcon 9 Heavy.

[93143]

Delta IV Heavy can also put up 25 mT. Falcon 9 Heavy is likely to be a lot cheaper, of course...

I think it's pathetic that we consider 25 mT heavy lift. Von Braun didn't call something heavy lift until it could do 100 mT. But we don't have anything anywhere near that size, unless you count Energia (mothballed) and the Shuttle stack (can't fly without the shuttle, and NLS/DIRECT doesn't exist (yet?)...

It's a shame no one developed Sea Dragon...

[KitemanSA]

If they want cheap, they should consider the KITE-HASTOL system.

[Skipjack]

I am a space enthusiast, but this seems very out there to me.
I cant imagine this to be competitive at todays launch costs, even with Falcon 9 heavy. Definitely not with any of the ULAs offerings.
This is a proof of concept or a publicity stunt at best.
But...if they get it to work, it might motivate some long overdue and necessary developments.
I am just glad it aint my money.

[djolds1]

If they want cheap, they should consider the KITE-HASTOL system.

IF you want CHEAP, consider a disposable ram accelerator.

Duane

[KitemanSA]

If they want cheap, they should consider the KITE-HASTOL system.

IF you want CHEAP, consider a disposable ram accelerator.

For bulk materials, this may be so, but for modules in the 5-15Mg range, it won't work and KITE-HASTOL would. The K-H would also almost eliminate the need for orbital transfer boosters.

By the by, why disposable? A rechargable, reusable unit would surely be better.

[djolds1]

If you want CHEAP, consider a disposable ram accelerator.

For bulk materials, this may be so, but for modules in the 5-15Mg range, it won't work and KITE-HASTOL would. The K-H would also almost eliminate the need for orbital transfer boosters.

Sufficient power (polywell, SPS, whatever) and beamed power/laser boost has the potential to revolutionize orbital boosters.

By the by, why disposable? A rechargable, reusable unit would surely be better.

That's the same mistake we made with the shuttle. One shot can be built to looser tolerances, using materials that only need to resist stresses for one cycle that is a fraction of a second long. As the Sea Dragon study in the '60s showed, CHEAP does not equal "notionally efficient."

Duane

[KitemanSA]

By the by, why disposable? A rechargable, reusable unit would surely be better.

That's the same mistake we made with the shuttle. One shot can be built to looser tolerances, using materials that only need to resist stresses for one cycle that is a fraction of a second long. As the Sea Dragon study in the '60s showed, CHEAP does not equal "notionally efficient."

But using a material that can hold it for that half cycle and release, then return to start again could be even cheaper given the repetition rate possible. And by the way, the Slingatron may be better than the ram accelerator anyway. Derek is building one on his own nickel. I can't wait to see how it works.

[pfrit]

By the by, why disposable? A rechargable, reusable unit would surely be better.

That's the same mistake we made with the shuttle. One shot can be built to looser tolerances, using materials that only need to resist stresses for one cycle that is a fraction of a second long. As the Sea Dragon study in the '60s showed, CHEAP does not equal "notionally efficient."

But using a material that can hold it for that half cycle and release, then return to start again could be even cheaper given the repetition rate possible. And by the way, the Slingatron may be better than the ram accelerator anyway. Derek is building one on his own nickel. I can't wait to see how it works.

My problem with reusable systems is that they always return to the "You only have to build it once" argument. For that to work, you need an economies of scale solution. You need 100 hundred launches a year to compete and we have never needed that level of space access yet. Further, the single use rockets get cheaper the more you launch as well. For a reusable system to be a practical solution, it needs to be cheaper on the first launch. OK, if it gets cheaper by the third launch, that would probably work as well. The problem is that they never seem to. The only hope I have there is Armadillo Aerospace (seriouly cool group). Check them out. They might get really cheap LEO in the end with a reusable system. Their approach is a get your hands as dirty as early as possible and see what you get. They also believe in keeping their day jobs at the same time.

[KitemanSA]

My problem with reusable systems is that they always return to the "You only have to build it once" argument. For that to work, you need an economies of scale solution. You need 100 hundred launches a year to compete and we have never needed that level of space access yet.

For the ram accelerator system under discussion, we are talking potentially hundreds of shots A DAY. The idea is to put up the massive satellite a square meter at a time with the chemical equivalent of a rail gun.
I would want to make that system reusable. The "barrel" need NOT be a pressure containment vessel, it only needs to hold the fuel mix until the sabot reaches that volume. It can then release under the jet pressure and reform later.

[pfrit]

My problem with reusable systems is that they always return to the "You only have to build it once" argument. For that to work, you need an economies of scale solution. You need 100 hundred launches a year to compete and we have never needed that level of space access yet.

For the ram accelerator system under discussion, we are talking potentially hundreds of shots A DAY. The idea is to put up the massive satellite a square meter at a time with the chemical equivalent of a rail gun.
I would want to make that system reusable. The "barrel" need NOT be a pressure containment vessel, it only needs to hold the fuel mix until the sabot reaches that volume. It can then release under the jet pressure and reform later.

Thats exactly the point. We need ~100 launches a year total for the whole world. Not hundreds a day. That includes the launches of the world wide military. Yeah, they are all going to use the same launch system. There just is not a market for a system like that.

[kurt9]

Theres only the little matter of developing the heavy-lift launch vehicles to put Solaren's SPS's into orbit. A minor detail.

Falcon 9 Heavy.

Something a lot bigger than this is necessary to put up an SPS with respectable power generating capacity.