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Diamonds Are A Space Station's Best Friend
strredwolf writes: "Research is being done to replace standard solar cell pannels commonly used in satelites with one's made with diamonds. Supposedly, they would be more durable to conditions in space, as well as generate more power at the same cost. Same cost? The kicker is that they're not using gem-quality diamonds. Article on Beyond 2000, which amazingly is still around." Note: this is still a work in progress, not a finished technology, but if it pans out, this offers several benefits over traditional solar cells.
The prime cost of putting things into space is not material, but the rockets you build to put them up there. Diamonds are much more dense than silicon or GaAs (the solar cell of choice in space nowadas, so the article is kinda wrong), so they will be correspondingly more massive.
You're talking about a film a few tens or hundreds of microns thick on a sheet of metal.
The density of the diamond film is moot point.
Even if you deposit both a metal film and a diamond film on top of a lighter substrate (like mylar or another plastic), 1) the metal film will still outweigh the diamond film - it has to be thicker, because it's carrying current sideways instead of axially, and 2) the weight of the plastic backing will be much more than the weight of either of the films, because you'd only be using a backing if you could make the films very thin (otherwise you'd just use the thicker metal layer as the backing - this is a space environment, it doesn't have to be very strong).
OK, since they don't teach this in school any more, I'll try to explain.
One's is a contraction of "one is," or the possessive of "one."
Ones is the plural of one.
- Have a picture
You can still get synthetic star sapphires. Wholesale, even. See SyntheticGems.org, a Thai manufacturer. You can even get sapphire bar stock. Linde Chemical did make a particularly nice star sapphire, though.
The price of gemstone diamonds is propped up by the increasingly frantic efforts of the De Beers Consolidated Selling Organization Ltd, the people behind the "A Diamond is Forever" promotion. But that's for gemstones. Most industrial diamond is synthetic.
DeBeers is currently fighting attempts by synthetic diamond manufacturers to move into gemstones. They fear a repeat of the star sapphire debacle. Around 1970, Linde Chemical started manufacturing and promoting synthetic star sapphires, using the name The Linde Star. They glutted the market and the price of sapphires went way down. Then Linde exited the business, and others took the price even lower.
The prime cost of putting things into space is not material, but the rockets you build to put them up there. Diamonds are much more dense than silicon or GaAs (the solar cell of choice in space nowadas, so the article is kinda wrong), so they will be correspondingly more massive.
Sure diamonds may have higher efficiency, but what they should also worry about is Watts/mass, not just efficiency. As long as W/m of GaAs is higher, they should think hard before switching.
Still, ranting over, it's a real cool technology. Imagine, building a zillion nano-vacuum tubes!
Mode (3) smart-aleck mode. Press * to return to main menu.
Really excellent expose' on the DeBeers cartel and how they create an artificaial scarcity of diamonds worldwide to keep prices from falling below that of aluminum.
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There is much cruelty in the universe, John.
Yeah, we seem to have the tour map.
The worldwide diamond market is cornered by ONE COMPANY. (Someone find the name for me, thanks.)
They carefully control the quantity and quality of diamonds released to the public so that the level of supply and demand remains constant.
There are so many diamonds available that if even a fraction of them were released the value of diamonds would fall to nothing.
If it were not for this fact, I would assume that synthetic diamonds would be far more expensive than real ones.
But I feel synthetic gems would be required for manufacturing since you would have a billion identical.
http://en.wikipedia.org/wiki/2004_U.S._Election_c
If you had read the article you would have seen that they were talking about using synthetic diamonds:
Instead it uses thin films made up of millions of microscopic diamond crystals. Polycrystalline diamond films can be made artificially from methane, through a process called chemical vapour deposition.
The article claims this will get 10W/cm^2. Sunlight in earth orbit gives a power level of 1600 W/m^2 = 0.16W/cm^2.
Possibly the plan is to use mirrors or plastic Fresnel lenses to focus the light onto small spots of diamond thermionic emitters. This would help explain how they are going to get the high temperatures needed for thermionic emission -- but the article doesn't say. Lousy reporting.