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damienpaul
2004-Nov-08, 11:29 AM
Hi again folks, how are you all?

I am just wondering about the feasibility of placing solar panels on Mercury or on the Moon or whereever - is it at all feasible and if so, how could the power be 'transmitted' back to earth?

Damo

antoniseb
2004-Nov-08, 01:20 PM
Originally posted by damienpaul@Nov 8 2004, 11:29 AM
I am just wondering about the feasibility of placing solar panels on Mercury or on the Moon or whereever - is it at all feasible and if so, how could the power be 'transmitted' back to earth?
Putting large solar power collecting devices on the Moon or Mercury is something that would probably be done by finding a way to manufacture them on-site. Doing it with today's technology would not be very practical, but sometime during this century it should be possible.

I suspect that the business of transmitting it back is tougher. A growing industry on the moon will probably need all the power you can generate up there, so the answer is that you'd transmit some of it back to Earth in the form of manufactured goods.

wstevenbrown
2004-Nov-08, 03:17 PM
One down and dirty method of on-site manufacture would be to commit to local production of amorphous silicon solar cells. This is a much lower-tech approach than crystalline solar cells. Basic requirements:
1) Refine silicates into mostly-pure silicon and or SiO2-- either will do.
2) Form material into sputtering target (this is a term of art-- essentially, an electrode of uniform density and a specific geometry.).
3) Sputter-- this is a bass-ackwards magnetron, a vacuum tube with strategically placed magnets -- you add high voltage at high vacuum with the intention that your cathode will evaporate away, and deposit on some surface you have placed in the way.
4) Etch and dope circuitry.
All of the above are technically feasible, in a payload smaller than a tractor-trailer truck, now.
Amorphous solar cells have been around since the 70's. Web-search keywords: Stanford Ovshinsky, Energy Conversion Devices, Ovonics. The cells have excellent mechanical properties, they are tough and flexible. The efficiency is only about 50% (crystalline versions approach 85%), but by way of compensation, they are cheap to make, and the economies of scale are HUGE. For info on commercial Si sputtering, consult Singulus Gmbh, a German-based corp who has been doing it for years (have done it myself, in making CD's and DVD's).
These cells will work 24/7/365.25 anyplace that is free of atmosphere and out of planetary shadow, for 60+ years. They work, with reduced efficiency, on rotating planets with atmospheres.
My apologies to those who have heard this rant before-- Steve

antoniseb
2004-Nov-08, 03:23 PM
Originally posted by wstevenbrown@Nov 8 2004, 03:17 PM
The efficiency is only about 50% (crystalline versions approach 85%...
Steve, you post some great stuff. In this particular case, I think your numbers are a little off. I think the current efficiency numbers for these to things are 5% and 15% with exotic materials permitting efficiencies up to about 35%. These are off-the-cuff numbers, since I haven't looked them up, but I'm curious as to where you got your numbers.

BTW, even at 5% amorphous solar cells manufactures in quantity on the Moon could be a good deal, so the rest of your line of reasoning is still fine by me.

wilbut
2004-Nov-08, 09:31 PM
There have been experiments using microwaves to transmit electricity, and there have even been a few science fiction books to take up the issue, the earliest one that I can think of was I, Robot by Isaac Asimov. (c. 1941).

I think the main issues are safety (who wants a giant microwave pointed towards their town?) and scalability (how to build the large scale solar farms, as well as the receiver/collector on earth). I think the best location might be one of the Lagrange points, probably L1 (which is the same location as the SOHO satellite).

Since the earth rotates in respect to the sun, there would need to be multiple receivers on earth, and the beam directed to the nearest receiver.

See also the FreeDictonary entry for Microwave Power Transmission (FreeDictionary - MPT (http://encyclopedia.thefreedictionary.com/Microwave%20power%20transmission))

antoniseb
2004-Nov-08, 09:45 PM
Originally posted by wilbut@Nov 8 2004, 09:31 PM
There have been experiments using microwaves to transmit electricity
Yes that's true, and these were intending to support power transmission from geosynchronous orbit, which is ten times closer than the moon, and four thousand times closer than Mercury. There are some practical matters involved with making the transmitting and receiving arrays which would be costly to surmount.

Safety is another issue which should not be discounted

suntrack2
2004-Nov-09, 10:33 AM
also on proxima and alfa centaury to fix it,
energy transfer thgough wireless mode to a nearby space station's transformer and again to the lower hight space station and then it will reach to the main transformer station on the earth whose antena will be more heighted, there will be need to make a magnetic connection for this mode and the intensity to reach the earth must be smooth and lower otherwise it will distruct. this phenomena is quite imaginative still today but in future to search the remedy of the mass failure of electricity on earth we have to find some great solutions in advance so that it can be implement in next 25 years, damien, what do you think?
moon may be a prospective for this sort of experiment.


sunil

damienpaul
2004-Nov-09, 10:52 AM
I think with enough vision, enough know how, enough money and possibly frasers backyard we could make this happen!

Matthew
2004-Nov-10, 01:12 AM
No, not feasibly.

We are looking at >40% efficiency with organic solar cells that can absorb much more of the light spectrum. Though they need replacing more often these organic solar cells are much cheaper to porduce. Putting solar cells on the moon will happen, but it will be used to only power the facilities on the moon.

Guest
2004-Nov-10, 01:50 AM
Most of you are way too far off on this.

In the 1990's many articles were written about Solar Power Satillites (SPS). They would orbit the Earth in geo-sychrnous orbits and send the power to the Earth to anennae fields in the form of micro wave energy wher it would then be converted to electricity. Very efficient too.

Remember, in space around good ole terra ferma the sun shines 4 times more powerful than on the surface and there are no cloudy days.

No need to go to Mercury.

Read up on them. Really kool idea. Non-poluting and no atomic wastes to worry about.

One way to utilize space fast and close.

Matthew
2004-Nov-10, 05:25 AM
Yes but those reports never mentioned how to effectively get that energy back to earth. Due to the distance between geo-sync orbit and earth's surface the enrgy being transfered via microwaves would be >100m (something around there) in diameter. And if it was a cloudy day the entire energy would be lost. The plans never developed, not because it wasn't a good idea, but because the energy could not be brought back to earth for use.

antoniseb
2004-Nov-10, 01:50 PM
Originally posted by matthew@Nov 10 2004, 05:25 AM
The plans never developed, not because it wasn't a good idea, but because the energy could not be brought back to earth for use.
Budget had a little something to do with it, as well as concern for migratory birds.

Matthew
2004-Nov-11, 06:53 AM
Yeah, money always has something to do with it. Migratory birds is a reson I never heard of though.

damienpaul
2004-Nov-11, 07:54 AM
strap solar panels to migratory birds then....

Guest or anyone are there any links to this kind of info?

Guest
2004-Nov-16, 03:40 PM
It was the budget that tanked the great idea. As for the location it would need a relatively cloud free spot (read desert area). Most likely Southwest USA,and North Africa.

donaldpilz
2005-Jan-05, 09:25 PM
Hey! Try this way, instead of solar panels on mercury and because of mercurys extremely slow rotation,lets set up shop at it's poles and use high energy laser stations. Convert the suns rays into laser energy and beam to our earth or moon. There must be a confort zone at both poles where it's not exremely hot or cold but just right so as to not cook or freeze huge mirrors or large magnifying lenses that convert the concentrated suns rays into a powerful laser beam which is reflected to another transfer station in geo-orbit above mercury. The laser beam is received then directed to a receiving station in earths orbit. This laser beam can be used for transportation and communications that will ferry supplies, equipment and humans back and forth from mercury to earth.The laser ship would be shaped like an hourglass and hollow where both halves meet so enough of the beam can pass through to the receiving station in eithers orbit. Both halves would contain fuel that would provide thurst to accelerate and decelerate using 90% of the laser beam as an igniter and push against the ship. The center of the hourglass shaped craft is where the crews quarters are located in a large revolving cicular cylinder that will provide artificle gravity. Both tranfer stations are also receiving stations ( you have to slow the ship at some point) that's when the ship moves out of the beam waits for the beam to be refected back to the other half of the ship and ignite the fuel to slowly decelerate. Heck, if Bush wants to spend 150 billion to go to Mars, I suggest my idea and get more bang!! for your buck!! You'll also get to mars faster and safer. ( NO MORE USING PLANETS TO SLINGSHOT AROUND THE SOLAR SYSTEM !!!!! ) Also I read they detected hydrogen on Mercury which usually indicates frozen ice ( I wonder if it turns liquid underground in the comfort zone ?? My e-mail is donaldpilz@yahoo.com Try to use constructive comments and I look forward to your comments. Donald

ChromeStar
2005-Jan-06, 08:17 PM
The laser idea is intresting but who wants a big laser pointing directly at the planet? :unsure:

I personally believe that advances in fusion are the best way to provide power but if you were to build such a "power plant" perhaps sending power by radio might be possible it would'nt cause risk of an overdose of microwaves here on earth or anything. :huh:

while on the idea of fusion why not set up automated fusion reactors on the planet there would be plenty of He3 fuel from the solar wind and and the plant could be some where inbetween the intense heat and cold?

then perhaps radiowaves could carry power?

antoniseb
2005-Jan-06, 08:45 PM
Originally posted by ChromeStar@Jan 6 2005, 08:17 PM
The laser idea is intresting but who wants a big laser pointing directly at the planet?
People have this crazy idea that lasers keep light from dispersing. Laser photons disperse like any other light, based on the size of the focussing lens or mirror. A Laser from Mercury will not keep the energy beam tight enough to make it worth while to catch the light again hear on Earth. Radio/Microwaves are even worse because the wavelength is so long.

I said this earlier in this thread. Generating power on Mercury is a good idea, but you should plan to use that power on Mercury.

Skywise
2005-Jan-06, 09:07 PM
Originally posted by Guest@Nov 10 2004, 01:50 AM
No need to go to Mercury.
[QUOTE]

Not just no need to go to Mercury... the challenges involved would be significantly greater. Remember, the side of Mercury facing the sun heats up enough to melt lead, while the side away from the sun drops to not far above absolute zero.

John L
2005-Jan-06, 10:44 PM
In the next decade NASA plans to include a test of laser communications from Mars to the Earth and back. Higher data rates are the benefit. I can't remember where I read the article, but supposedly NASA has worked out the focus problem so that the beam, which would have spread to hundreds of kilometers across can now be focused to a few kilometers across over the Earth Mars distances. I still wouldn't want a laser carrying gigawatts of power aimed at the Earth, though, no matter where the receiving station is built.

An there's nothing wrong with sticking the receiving station in the middle of the desert. We have power grids that stretch across continents, so we should be able to tie receiving stations built anywhere into a grid.

Svemir
2005-Jan-07, 10:10 AM
Simply, use lasers to boil water some place in Pacific (it couldn't be worse then dropping nukes around) or any other ocean, and use it like an ordinary power plant.
Watch out for sharks and penguins!

ChromeStar
2005-Jan-08, 11:22 AM
if you beamed a laser towards the earth in a straight line, the light would disperse, agreed.

...but what if the light was "dispersed" to begin with, would it disperse back into a staright line? - Know what i'm saying?

So basically by the time the laser light gets to earth it has starightened it self.