Solar or Fusion?

[Moontanman]

Im not sure how you managed to do it, but that post links to itself :)

 

Aneutronic fusion just means it releases most of its energy (>99%) in forms other than that of neutrons.

 

Even if all the energy produced by this fusion was electromagnetic energy and it was all captured by appropriate photovoltaic cells, they themselves only yield 10-15% efficiency..

 

I know what aneutronic means it would be a huge break through in energy production because it's neutrons that are so hard to sheild against. Photovoltaic cells are getting more effecent every day and any left over energy could be used to drive stirling type engines to generate extra eletricity all with no dangerous nuclear waste to store for 10,000 years. BTW I looked it up and nuclear power fuel reserves are good for another 15,000 years at least. controled aneutronic fusion would also mean a great deal to space travel. Imagine an engine with both power and a high specific impulse. Pluto would only be weeks away instead of decades.

I am very much pro nuclear power but the technology must be brought out of teh 1950's and into the 21st century. We are using out dated tecnology by at least 50 years in our reactors. here is my favorit type of space craft design. I hope to live long enough to see a real space ship' this lis is to a series of articals about nuclear powered space vehicals. It's the only way to go but you have to read them all to get a true understanding of what is being proposed. Here is the link.

 

NuclearSpace: Opening the Next Frontier pt. 1

 

Michael

[Jay-qu]

Its not just about the neutron shielding its the fact that these fast moving neutrons run off with a lot of the energy from the fusion process, so if you can find a reaction that doesnt emit neutrons, it must give its energy in other, more readily usable forms.

 

Has there been any research into using the energy the neutrons run off with? How could one theoretically harness kinetic energy from a neutral particle..

 

You say 15,000 years. Im not sure what that figure is going on but Im sure mine and Craigs analysis captures the essence of the argument. Yes there is a lot of uranium, but a lot of it is not readily usable.

 

Space travel, well thats a whole 'nother kettle of fish! :)

[Pyrotex]

...Space travel, well thats a whole 'nother kettle of fish!

'Bout ten years ago, I was shown a hard copy of a journal article on fusion space propulsion. It was damn near a detailed set of blueprints--all worked out. It used the magnetic bottle concept with a magnetic mirror at each end. One end could be made "leaky" and that provided the thrust.

 

The "bottle" was huge, maybe 100 meters long and 10 meters wide, built of liquid N2 cooled carbon composites; a latticework like a cylindrical Eiffel tower. No shielding of any kind except that needed to protect the individual spars of the latticework--and a disk at the foreward end to protect the manned compartment. The fusion was litterally open to space. Which was why the sucker glowed about 1/10 as bright as the Sun, when it was ignited in Low Earth Orbit.

 

Can't do that kinda thing on the Earth's surface. :eek_big:

[Jay-qu]

'Bout ten years ago, I was shown a hard copy of a journal article on fusion space propulsion. It was damn near a detailed set of blueprints--all worked out. It used the magnetic bottle concept with a magnetic mirror at each end. One end could be made "leaky" and that provided the thrust.

 

So if it was in a journal we could go and find it! any idea which journal it was in and perhaps a more specific date? :phones:

[Pyrotex]

So if it was in a journal we could go and find it! any idea which journal it was in and perhaps a more specific date?

:hyper:

 

It was a Xerox copy of a magazine article given me by a fellow engineer when I worked at another company, and it got packed in boxes with lots of other paper, and ... well ... it's lost. :thumbs_up

 

Might be able to Google it, but I can't promise nuffin'.

[Jay-qu]

:hyper:

 

It was a Xerox copy of a magazine article given me by a fellow engineer when I worked at another company, and it got packed in boxes with lots of other paper, and ... well ... it's lost. :thumbs_up

 

Might be able to Google it, but I can't promise nuffin'.

Thats better than promising nothing

 

some alternative solar power concepts:

EnviroMission Ltd.

[CraigD]

some alternative solar power concepts:

EnviroMission Ltd.

”Solar towers” such as the one Jay links to are, IMHO, a very promising solar technology.

 

These solar-thermal-mechanical generators addresses the significant concern raised earlier in this thread

This biggest problem with solar is keeping your lights on at night.

It’s possible to “throttle” a solar tower so that is accumulates hot air during the day, and continues to power its turbines to generate electricity during the night. They’re very flexible systems, capable of shaping their 24-hour output profile to changing demands, such as summer AC (cooling) or winter electric heating.

 

The main disadvantages of these systems, as best I can tell, are size – they occupy much more surface area than a fuel-burning electric generator plant of the same power – and the related need for strong sunlight, making them, as with most solar power systems, ill-suited for places with many cloudy days, or high latitudes where winter days are very short. No simple ground-based solar power system appear suited to use above the Artic/ Antarctic circles – those days with no sunrise pretty much doom them.

[DougF]

I voted for number 1,

I think Solar well be the best bet as energy resource to expand upon.

My favorite "tidal generators" still growing but holds great promise.

 

Marine Energy - Tidal Power

[Moontanman]

This is the next step in nuclear, fusion is just a pipe dream.

 

Sustainable Nuclear Energy Moves A Step Closer

 

Michael

[Jet2]

Solar may die one day though it may be very loooooooooooong after.

So come up new energy source would be best solution. And yet that would be more than one if we are lucky enough.

Of course it's our challenge...or, is it?

[InfiniteNow]

Solar may die one day though it may be very loooooooooooong after.

So come up new energy source would be best solution. And yet that would be more than one if we are lucky enough.

What do you even mean by the above? It makes no sense. The sun will outlast just about all life on earth, and any life still around at that point will die along with the sun. So, was your comment specific to the technology of photovoltaics somehow, and if so, let me ask, what you even mean? Is this a plea for a matter/antimatter-anihilation-type plan? ;)

 

 

Little darlin' I feel the ice is slowly meltin'. :)

[Jet2]

The sun will outlast just about all life on earth, and any life still around at that point will die along with the sun.

 

Why are you so sure?

And does it has to be that way, and why?

 

was your comment specific to the technology of photovoltaics somehow, and if so, let me ask, what you even mean? Is this a plea for a matter/antimatter-anihilation-type plan?

 

You may say I just have wishful thinking, but why not?

Better ask a real scientist around here @ Hypography for your above questions for I am not able to provide any answer.

[InfiniteNow]

Why are you so sure?

And does it has to be that way, and why?

I concede that I cannot be certain, however, I have a high degree of confidence in my comment due to understanding of the various systems involved in extinction, anthropology, biology, and solar processes (among others).

 

 

You may say I just have wishful thinking, but why not?

Why not, indeed. I completely agree that we should always seek improvement. However, a desire to seek improvement does not validate a claim that solar is not our best current option. I think we're more aligned here than not, so no worries. :)

[CraigD]

Solar may die one day though it may be very loooooooooooong after.

The sun will outlast just about all life on earth, and any life still around at that point will die along with the sun.

Everyone appears correct on the subject of the future of the sun. To put the usual number to it, the Sun is expected enter a period of greater luminosity circa 5,500,000,000 AD, peaking as a red giant circa 7,700,000,000 AD. Though a bad time for biological life on Earth, with little atmosphere and such stuff as molten metal pools on its surface, with a luminosity about 2400 times greater and 4 times closer, and thus solar power about 40,000 times greater for the same collector area, it would be a great time for solar! B) According to best current theory, things get complicated and chaotic shortly after that, settling into a basically “lights out” white dwarf phase circa 7,865,000,000 AD (good source: OSU’s “The Once & Future Sun”)

 

As Jet puts it, all these events are looooooooooong in the future, so far that the hypothesis that there’ll be no intelligent life will be around to care about it is quite reasonable. In more optimistic extropian scenarios, however, the end of the stelliferous era, when not only the Sun, but all stars in the universe cease to be major power sources, marks a future “energy crisis” beside which the one expected in the next few decades pales. During this period, circa roughly 100,000,000,000,000 AD, whatever, if any, advanced engineering life there is in the universe will have to shift their technology from star-based to, it appears, black-hole based. This will buy them a lot more time – until at least circa 100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,

000,000 AD, at most circa 100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,

000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,

000,000,000,000,000,000,000,000,000 AD. However, this shift accomplished, power is still pretty much power, and business (whatever that may be) should be able to continue pretty much as usual.

 

Speculating about such far future events as any of the above stretches the limits of science and imagination so far that there’s a great chance that nearly all of our speculation, and the critical physics underlying it, is wrong, and it will be nothing like we imagine. Still, this doesn’t stop a people from writing a lot of excellent science fiction and non-fiction on the subject.

 

Considering engineering power on such a high level emphasizes a fact somewhat obscured by the title of and discussion in this thread: Solar energy IS fusion energy, just natural fusion in the sun, not the artificial sort that’s proved so difficult to adapt to civil needs.

 

Other sort of power – fossil fuel, electric battery, stored hydrogen, etc. – are really just a storage technology for energy produced by the Sun’s fusion, and gathered in some way by natural and artificial means by Earth. Wind and hydroelectric are driven by the energy influx from the Sun. Nuclear is due to supernova remnant elements – Uranium, etc – formed via fusion in long-gone stars. Though space if full of free hydrogen, there’s hardly any conceivable way of getting power from it other than by it coalescing into stars.

 

Tidal power, and future technologies such as Electrodynamic tethers on the moons of giant planets, are an exception to the “all energy is fusion energy” rule, getting their energy from the kinetic energy of large bodies. One might term this other class of energy sources “lunar power”.

[cfrjlr]

Space-Based Solar Power Interim Assessment (Release 0.1) is Published!

Posted by Coyote on October 10, 2007

 

Hello Everyone!

 

Click here for the “Interim Assessment!” (security does not allow links to be embedeed so you need to click on my profile CFRJLR for link to my personal site wiht more details)

 

From the Foreword of the report itself:

 

Preventing resource conflicts in the face of increasing global populations and demands in the 21st century is a high priority for the Department of Defense. All solution options to these challenges should be explored, including opportunities from space.

 

In March 2007, the National Security Space Office’s Advanced Concepts Office presented the idea of space‐based solar power (SBSP) as a potential grand opportunity to address not only energy security, but environmental, economic, intellectual, and space security as well. First proposed in the late 1960’s, the concept was last explored in the NASA’s 1997 “Fresh Look” Study. In the decade since this last study, advances in technology and new challenges to security have warranted a current exploration of the strategic implications of SBSP. For these reasons, my office sponsored a no‐cost Phase 0 Architecture Feasibility Study of SBSP during the Spring and Summer of 2007.

 

Unlike traditional contracted architecture studies, the attached report was compiled through an innovative and collaborative approach that relied heavily upon voluntary internet discussions by more than 170 academic, scientific, technical, legal, and business experts around the world. I applaud the high quality of work accomplished by the team leaders and all participants who contributed in the last six months. I encourage them to continue their work in earnest as they move beyond this interim report and seek to answer the question of whether SBSP can be developed and deployed within the first half of this century to provide affordable, clean, safe, reliable, sustainable and expandable energy for mankind.

 

This interim assessment contains significant initial findings and recommendations that should provide pause and consideration for national and international policy makers, business leaders, and citizens alike. It appears that technological challenges are closing rapidly and the business case for creating SBSP is improving with each passing year. Still absent, however, is an appropriate catalyst to stimulate the various interested parties toward actually developing a SBSP capability. I encourage all to read this report and consider the opportunities that SBSP presents as part of a national and international debate for action on how best to preserve security for all.

 

//signed 9 Oct 07//

JOSEPH D. ROUGE, SES

Acting Director, National Security Space Office