Let There Be Light: Germans Switch on 'Largest Artificial Sun' (theguardian.com)

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Let There Be Light: Germans Switch on 'Largest Artificial Sun' (theguardian.com)

Posted by msmash on Thursday March 23, 2017 @03:20AM from the let-there-be-light dept.

German scientists are switching on "the world's largest artificial sun" in the hope that intense light sources can be used to generate climate-friendly fuel. From a report: The Synlight experiment in Julich, about 19 miles west of Cologne, consists 149 souped-up film projector spotlights and produces light about 10,000 times the intensity of natural sunlight on Earth. When all the lamps are swivelled to concentrate light on a single spot, the instrument can generate temperatures of around 3,500C -- around two to three times the temperature of a blast furnace. "If you went in the room when it was switched on, you'd burn directly," said Prof Bernard Hoffschmidt, a research director at the German Aerospace Center, where the experiment is housed in a protective radiation chamber. The aim of the experiment is to come up with the optimal setup for concentrating natural sunlight to power a reaction to produce hydrogen fuel.

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Add some solar panels ... by Anonymous Coward · 2017-03-23 03:22 · Score: 1

... And you have the first solar powered sun!
"Accident" waiting to happen by volodymyrbiryuk · 2017-03-23 03:24 · Score: 5, Funny

"Hey Helmut I bet you can't last longer in there without sunscreen than on that beach in Spain last year." Helmut: "Hold mein bier."

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sudo rm -r -f --no-preserve-root /
1. Re:"Accident" waiting to happen by XXongo · 2017-03-23 05:03 · Score: 1
  
  "nimm mal mein Bier, Bube."
2. Re:"Accident" waiting to happen by codeButcher · 2017-03-23 07:09 · Score: 2
  
  Y'all have it all wrong though. There is no equivalent to the American, semi-inebriated uttering "hold my beer" ("beer", when referring to the stuff made in the USA, should be in air quotes) in German, and for the following reasons:
  * German beer is still proper beer full of natural goodness, not so dissimilar to that effervescent multivitamin some people like to pop into a glass of water and drink daily for good health. Only better tasting and more effective.
  * Germans grow up on beer. They drink it at breakfast instead of coffee or cacao. They have beer dispensers instead of water coolers at the office.
  * Germans don't get drunk. After consuming copious amounts of beer, their noses may turn red, but that's it.
  Source: I'm German myself. Also, if some humor-deficient mensch claims that Germans have no sense of humor, they may just find out how little humor I do have.
  
  --
  Free, as in your money being freed from the confines of your account.
3. Re:"Accident" waiting to happen by tinkerton · 2017-03-23 08:13 · Score: 1
  
  Of course Germans have to consume copious amounts of beer. It's far too light. There's this little country to the northwest of Germany which has real beer. AND a sense of humour. But no Mezger unfortunately. No I don't mean your name, it's without a T.
4. Re:"Accident" waiting to happen by thinkwaitfast · 2017-03-23 08:59 · Score: 1
  
  When I was in Ireland, all the Germans were drinking Budweiser.
5. Re:"Accident" waiting to happen by Pseudonym · 2017-03-23 12:49 · Score: 1
  
  Also, if some humor-deficient mensch claims that Germans have no sense of humor [...]
  I know Germans have a sense of humour. I've seen 7 Zwerge.
  
  --
  sub f{($f)=@_;print"$f(q{$f});";}f(q{sub f{($f)=@_;print"$f(q{$f});";}f});
6. Re:"Accident" waiting to happen by arglebargle_xiv · 2017-03-23 13:23 · Score: 1
  
  In any case it's nowhere near the world's largest artificial sun. That record is claimed by the one the Russians lit up over Novaya Zemlya in October 1961.
7. Re:"Accident" waiting to happen by Stuarticus · 2017-03-23 22:03 · Score: 1
  
  Well, to be fair there is no other beer in Ireland. I think St Patrick drove it out or something.
  
  --
  If you think someone isn't free to have a different definition of "freedom" you may be a tyrant.
Re:To Make Hydrogen Fuel?! by Anonymous Coward · 2017-03-23 03:36 · Score: 2, Informative

Another inane comment from the peanut gallery. While there is Hydrogen on the surface of the moon are you mistaking this with Helium-3? Otherwise your question makes no sense as if you want to refine hydrogen today the cheapest way to do it has nothing to do with space.
3500 degrees by tinkerton · 2017-03-23 03:36 · Score: 2

That's a lot really. What kind of lights are these?
The summary obfuscates this but whatever the amount of incandescent bulbs you are focusing on the same spot, you cannot get a temperature that is higher than the filament in the bulb (the black box temperature of the bulb). And 3500 is a lot for an incandescent bulb.
Maybe it's another kind of lighting then. Like a combination of different LEDs.
1. Re:3500 degrees by tinkerton · 2017-03-23 03:38 · Score: 2
  
  Another example: it's not possible to use mirrors to concentrate sunlight so that it can heat something up to more than 5500 degrees.
2. Re:3500 degrees by Stoertebeker · 2017-03-23 03:39 · Score: 2
  
  Likely arc lamps
3. Re:3500 degrees by tinkerton · 2017-03-23 03:50 · Score: 1
  
  Ah, I just looked it up and Xenon arc lamps can reach a color temperature of 6200K . So that's indeed a candidate.
4. Re:3500 degrees by Carewolf · 2017-03-23 04:35 · Score: 1
  
  That's a lot really. What kind of lights are these?
  The summary obfuscates this but whatever the amount of incandescent bulbs you are focusing on the same spot, you cannot get a temperature that is higher than the filament in the bulb (the black box temperature of the bulb). And 3500 is a lot for an incandescent bulb.
  Maybe it's another kind of lighting then. Like a combination of different LEDs.
  Okay. I will bite: Why not? You add energy from multiple lamps. Light superpositions and photons excites what they hit if they are absorbed, because they can't really do anything else. The maximum possible temperature at the focal point, shouldn't have anything to do with the original material.
5. Re:3500 degrees by ThePyro · 2017-03-23 04:41 · Score: 1
  
  I had the same question. It seems to me that the only limiting factors would be total power (shouldn't it scale linearly with the number of bulbs?) vs. the rate at which heat is removed from the target location via thermal radiation or convection.
  I suppose you'd also have to consider what happens when your target vaporizes, since you'd no longer have a solid object at the focal point to absorb the radiation.
6. Re:3500 degrees by Carewolf · 2017-03-23 04:44 · Score: 1
  
  I had the same question. It seems to me that the only limiting factors would be total power (shouldn't it scale linearly with the number of bulbs?) vs. the rate at which heat is removed from the target location via thermal radiation or convection.
  I suppose you'd also have to consider what happens when your target vaporizes, since you'd no longer have a solid object at the focal point to absorb the radiation.
  That is also the only way a relation to the filament material would make sense. If the target is made of the exact same material, it would vaporize at the maximum temperature of the filament. But why would it be the same material?
7. Re:3500 degrees by lorinc · 2017-03-23 04:44 · Score: 2
  
  Because when you mix 2 things at temperature T, it doesn't make a thing at temperature 2T. Don't mistake temperature for energy.
  
  --
  Video of some good progressive thrash music
8. Re:3500 degrees by Anonymous Coward · 2017-03-23 04:56 · Score: 2, Informative
  
  xkcd explains it well: https://what-if.xkcd.com/145/
9. Re:3500 degrees by tinkerton · 2017-03-23 05:00 · Score: 1
  
  Good one. I didn't know where to start , apart from oneliners that would show that I at least knew the reason but that would be no help for anyone who didn't.
10. Re:3500 degrees by Anonymous Coward · 2017-03-23 05:00 · Score: 2, Informative
  
  To sum it up, quoting from that link: Lenses and mirrors work for free; they don't take any energy to operate. If you could use lenses and mirrors to make heat flow from the Sun to a spot on the ground that's hotter than the Sun, you'd be making heat flow from a colder place to a hotter place without expending energy. The second law of thermodynamics says you can't do that. If you could, you could make a perpetual motion machine.
11. Re:3500 degrees by BenBoy · 2017-03-23 05:08 · Score: 5, Informative
  
  you cannot get a temperature that is higher than the filament in the bulb
  ... as explained here: Fire from Moonlight
12. Re:3500 degrees by tinkerton · 2017-03-23 05:34 · Score: 1
  
  I would add then that the second law forbids this because...
  In your closed system you could have a little pipe going back from the hot place to the colder place and attach an engine to it that converts the heat to electricity that leaves your closed system through a pair of wires Because we know how to do that very well, creating electricity when heat is transferred from a hot to a cold place. That is what all steam turbines and fuel based engines do. That would mean you could make free electricity.
13. Re:3500 degrees by dmatos · 2017-03-23 05:40 · Score: 2
  
  A bit of digging found another article that lists the type of lamp used.
  They're xenon short-arc lamps.
  
  --
  
  It may look like I'm doing nothing, but I'm actively waiting for my problems to go away.
  --Scott Adams
14. Re:3500 degrees by Diakoneo · 2017-03-23 05:43 · Score: 1
  
  I'm still confused. The XKCD cartoon shows a single source - the Moon, Sun, etc. But what they are doing here has 149 sources of energy. So if you had a binary sun (hypothetically identical suns) with two lenses, each focusing on a single spot - wouldn't that be 2x the temp? Isn't that a better example of what they are doing? And if you get things hot enough, could you start fusion which would then release vast amounts energy?
  
  --
  "Just as there is nothing so unreal as reality TV, there is nothing as unsocial as social media." - Alistair Dabbs
15. Re:3500 degrees by tinkerton · 2017-03-23 05:48 · Score: 1
  
  The xkcd cartoon is a good source but it may require multiple readings. It also shows a figure that is almost completely surrounded by sun and explains that it cannot get any hotter than the sun that way. The person can can hold a large magnifying glass it will make no difference at all.
16. Re:3500 degrees by gumbi+west · 2017-03-23 06:20 · Score: 1
  
  This is just another in an example of XKCD falling down on explaining to me. I don't get the thermodynamics argument at all. My model is that I can take photons and put them where I want to by having a demon move around a mirror and shot them all at one spot (kind of like Maxwell's demon, but this one has a mirror). Yes, this creates a super hot spot, but it didn't use any energy that didn't already exist. It just put it all in one place.
17. Re:3500 degrees by ThePyro · 2017-03-23 06:23 · Score: 1
  
  Does the following alternative explanation hold water?
  As your target object gets warmer, it radiates more and more of that energy into its surroundings. The energy loss to radiation actually grows much faster than the temperature of the object. According to the Stefan-Boltzmann Law, the net loss of energy is proportional to (T^4 - Tc^4), where T is your target's temperature and Tc is the temperature of its surroundings. So as the target approaches the temperature of the lights it begins to give up energy to radiation just as fast as it absorbs it.
18. Re:3500 degrees by gumbi+west · 2017-03-23 07:11 · Score: 1
  
  To answer my own question, the reason is that the amount of energy that can be captured is based on the temperature differences. So, if you could increase the temperature difference you could make energy.
  As for the demon, just like Maxwell's, it would decrease entropy and, in doing so, increase the amount of energy available.
19. Re:3500 degrees by Carewolf · 2017-03-23 07:37 · Score: 1
  
  Because when you mix 2 things at temperature T, it doesn't make a thing at temperature 2T. Don't mistake temperature for energy.
  ?? What are you smoking?
  Of course it isn't. But if you add two accelerations to eachother you get twice the acceleration. The stable temperature is based on where the acceleration and deacceleration of temperature meet (how much is added and how much is lost). When you add more, that balance changes upwards.
20. Re:3500 degrees by Carewolf · 2017-03-23 07:47 · Score: 1
  
  Because when you mix 2 things at temperature T, it doesn't make a thing at temperature 2T. Don't mistake temperature for energy.
  Wait, wait, wait.. Are you guys thinking about is a physical connected heat transfer? Then yes, adding two sources at 1000C will not get the temperature above 1000C (you need an active heat source and insolution for that). But this isn't a physical heat transfer. It is an energy transfer over light, and this case the new matterial unconnected to the old can have different material and different insulation. Using physical connected heat logic makes no sense here.
21. Re:3500 degrees by Agent0013 · 2017-03-23 08:01 · Score: 1
  
  Wouldn't that only be true if you were trying to focus the heat from a single lamp filament? When there are more than one you can aim the light at the target from all angles and you aren't focusing light down to a point, you are adding more and more light to all the points being lit up.
  
  --
  
  -- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
22. Re:3500 degrees by Agent0013 · 2017-03-23 08:05 · Score: 2
  
  But that is the light from one sun. The way I understood that "what-if" was the process has to work in reverse. The focused light at the point has to be traceable back to where the light came from. But when you shine two light bulbs at a sheet of paper, you are not using lens to focus one bulb, you have two of them on top of each other. If you stand in front of two infrared heaters you will get warmer than if in front of one of them. But they aren't trying to make their heat hotter than their source by magnifying it in the "what-if" way that does not work.
  
  --
  
  -- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
23. Re:3500 degrees by ortholattice · 2017-03-23 08:23 · Score: 1
  
  Because when you mix 2 things at temperature T, it doesn't make a thing at temperature 2T. Don't mistake temperature for energy.
  
  It depends on what kind of "mixing" you allow. You could have an array of 1000K lamps shining on solar panels, then combine the solar panel outputs to drive a small 2000K lamp. Certainly there would be a lot of energy loss in this system, but the temperature would increase to 2T.
  So without specifying the constraints on the collection system, you can't say that a 2T increase isn't possible. The solar cell method has only passive components, so passive alone is not sufficient to forbid a 2T increase.
24. Re:3500 degrees by thinkwaitfast · 2017-03-23 09:02 · Score: 1
  
  How are multiple lamp filaments any different than one large filament?
25. Re:3500 degrees by Gr8Apes · 2017-03-23 10:32 · Score: 1
  
  It's radiation being reflected and focused - multiple filaments can produce more of it for a given price than one larger filament. It's also easier to create the reflectors for smaller filaments, plus the source becomes more linear or point in form.
  
  --
  The cesspool just got a check and balance.
26. Re:3500 degrees by gumbi+west · 2017-03-23 15:40 · Score: 1
  
  Ask Maxwell how he did it.
27. Re:3500 degrees by gumbi+west · 2017-03-23 15:47 · Score: 1
  
  Right, but it maxes out when you have 4pi of heaters around you.
28. Re:3500 degrees by gumbi+west · 2017-03-23 15:48 · Score: 1
  
  I don't think the second law ever references little pipes.
29. Re:3500 degrees by tinkerton · 2017-03-23 20:18 · Score: 1
  
  I don't think mentioning the second law ever helps laymen understand the physics of the situation.
30. Re:3500 degrees by tinkerton · 2017-03-24 04:34 · Score: 1
  
  uh right, it's closer to 5.800 K. Must have confused with Celsius. But the idea is the same. I have no idea how hot mercury lights get. How much is 'insanely' in Kelvin? Mercury lights do not obey the normal temperature curves (ugly color) so I'm not sure how one should calculate with those.
  Also I wouldn't conclude anything from how hot a light gets. The surface temperature of a bulb is a lot lower than that of the filament bu it's a design choice of the bulb. The filament in a plain low wattage lightbulb is also around 3000K and you can almost touch the bulb. With a halogen lamp you can't but that is because they chose to make the bulb very small.
  The reason filament temperature is a limit is that even if you are completely, utterly surrounded with filaments, you cannot get hotter than those filaments. But then you're just inside a 3000k box.
31. Re:3500 degrees by gumbi+west · 2017-03-24 14:24 · Score: 1
  
  I don't know about that, but it can help physicists.
What could go wrong? by Anonymous Coward · 2017-03-23 03:43 · Score: 1

Krauts experimenting to build ultra high temperature ovens. Does that sounds like a good idea?
Phat sound system by darkain · 2017-03-23 03:45 · Score: 1

Am I the only one looking at the pics of this thing and being reminded of crazy ass phat sound systems from ridiculous music videos of the '90s?
1. Re:Phat sound system by tinkerton · 2017-03-23 04:24 · Score: 1
  
  If you were, then not anymore.
Typical by Harold+Halloway · 2017-03-23 03:45 · Score: 1

I'll bet the Germans have bagged all the best (artificial) sunbeds as well.
Obvious statement is obvious by freeze128 · 2017-03-23 03:45 · Score: 1

"If you went in the room when it was switched on, you'd burn directly,"

No kidding!
1. Re:Obvious statement is obvious by Anonymous Coward · 2017-03-23 03:51 · Score: 1
  
  Yes, best to stand a bit off to the side so that you only burn indirectly.
2. Re:Obvious statement is obvious by fisted · 2017-03-23 04:13 · Score: 2
  
  Ist just how ze krauts talk. "directly" (direkt) is used in the meaning of 'immediately' here.
  
  --
  CLI paste? paste.pr0.tips!
what a disappointment by fubarrr · 2017-03-23 03:52 · Score: 1

I almost thought that pesky Germans managed to get a positive q fusion reactor
1. Re:what a disappointment by Tablizer · 2017-03-23 05:45 · Score: 3, Insightful
  
  I know this is not fusion, but on that note, If Europe gets fusion to a practical level, it would be a yuuuuge embarrassment to the US, comparable to losing the space race. Plus, Europe will probably charge us for related patents, or at least they should: they shouldered most of the cost while we collectively denied global warming and bowed down to the Oil Gods.
  
  --
  Table-ized A.I.
2. Re:what a disappointment by balbeir · 2017-03-23 08:46 · Score: 1
  
  Defunding the Department of Energy pretty much guarantees that the USA will lose that race.
3. Re:what a disappointment by Tablizer · 2017-03-23 09:31 · Score: 1
  
  Mr. Perry will hopefully forget to cut his own Dept., if the debates were any indication.
  
  --
  Table-ized A.I.
Nope by PPH · 2017-03-23 03:53 · Score: 1

optimal setup for concentrating natural sunlight
But it's not. Sunlight is for all intents and purposes collimated due to the extreme distance of its source. While these lamps can be "swivelled (sp?) to concentrate light on a single spot", that will tell you little about the setup applicable for use with sunlight.

--
Have gnu, will travel.
1. Re:Nope by Carewolf · 2017-03-23 04:40 · Score: 3, Informative
  
  optimal setup for concentrating natural sunlight
  But it's not. Sunlight is for all intents and purposes collimated due to the extreme distance of its source. While these lamps can be "swivelled (sp?) to concentrate light on a single spot", that will tell you little about the setup applicable for use with sunlight.
  Have you heard about mirrors? And mirrors on swivels?
  See also Solar power towers
2. Re:Nope by Nemyst · 2017-03-23 05:12 · Score: 2
  
  A parabolic reflective dish can focus collimated light into a single point. It's been around for millennia.
3. Re:Nope by PPH · 2017-03-23 07:41 · Score: 1
  
  A parabolic reflective dish
  A single parabolic dish can. But a bunch of them "swivelled to concentrate light on a single spot" in no way emulates solar radiation at the earth's surface.
  I'm assuming that, as TFS says "The aim of the experiment is to come up with the optimal setup for concentrating natural sunlight". Well, a bunch of small parabolic dishes aimed at a single point is nothing like the typical reflector setup of a solar power tower. They are usually a bunch of flat mirrors that approximate a single parabola only over a large scale.. At the optical power densities they are using, the variation in radiation power density vs incident angle could be significant in collector design.
  
  --
  Have gnu, will travel.
4. Re:Nope by Anonymous Coward · 2017-03-23 08:53 · Score: 1
  
  Sunlight is for all intents and purposes collimated due to the extreme distance of its source.
  
  Except it is huge! It covers about 1/2 a degree in the sky so its light is poorly columned.
  
  While these lamps can be "swivelled (sp?) to concentrate light on a single spot", that will tell you little about the setup applicable for use with sunlight.
  Another arm chair scientist on Slashdot. When you build a sunlight concentrator the light comes in from many angles, just like with these lamps. They aren't trying to test a concontrator, they are trying to simulate one, so they can test what is done (making H2) with the light.
Solar panels! by the_skywise · 2017-03-23 04:06 · Score: 1

If they could just get solar panels with 101% efficiency!
1. Re:Solar panels! by Tablizer · 2017-03-23 05:48 · Score: 1
  
  If they could just get solar panels with 101% efficiency!
  Excellent: hookem up to an EM-drive, and we be trekkin', baby!
  
  --
  Table-ized A.I.
Star Trek by rfengr · 2017-03-23 04:22 · Score: 1

Now what were the parasites in ST TOS that could only be killed with strong sunlight? Spock had the extra eyelids, then Bones figured out only UV was needed.
Re:How about actual sunlight instead of projectors by tinkerton · 2017-03-23 04:28 · Score: 1

It's called thermolysis: water will dissociate at temperatures above 2500K.
Re:How about actual sunlight instead of projectors by tinkerton · 2017-03-23 04:31 · Score: 1

No that's too high. 2000K is enough
3500-Degrees? by xession · 2017-03-23 04:31 · Score: 1

And they're using zip ties? And they don't melt? Maybe I'm misunderstanding the suggestion that I would instantly burn walking into this room but I'm fairly sure zip ties burn at a lower temperature than I do.
Re:How about actual sunlight instead of projectors by gman003 · 2017-03-23 04:36 · Score: 4, Funny

640K ought to be enough for anybody.
Re:How about actual sunlight instead of projectors by tinkerton · 2017-03-23 04:41 · Score: 2

... Edison said, as he presented the first commercial lightbulb. It glowed slightly red in the dark.
Artificial Sun? by fahrbot-bot · 2017-03-23 05:22 · Score: 1

Can I use this to power my solar panels at night?

--
It must have been something you assimilated. . . .
Re: How about actual sunlight instead of projector by fubarrr · 2017-03-23 05:28 · Score: 1

Cheap as crap hydrogen capture is as simple as capturing hydrogen from bwr nuclear reactors. Even tiny scientific reactors with 6000kw like power can split 20 kg of water per hour
Hey Sunny? by Neuronwelder · 2017-03-23 06:57 · Score: 1

Wouldn't it be cheaper just to play with magnifying glasses and the real sun? After all, won't the real sun will be used to produce hydrogen? Ahh.. Maybe they had some extra electricity from all those solar cells they have, and had nothing better to do with it.
1. Re:Hey Sunny? by Blaskowicz · 2017-03-23 08:38 · Score: 1
  
  Can't we mine the hydrogen from the sun? It's such a waste to fuse that hydrogen, transport the resulting energy to the Earth - an extremely minute proportion of which reaches Earth as visible or infrared light, the rest is wasted by being radiated isotropically to space - then use the light to break up water and make hydrogen again.
A 100% natural version by orsayman · 2017-03-23 07:06 · Score: 1

It reminds me of solar furnaces (like this one https://en.wikipedia.org/wiki/...). Quite funingly the temperature and light intensity are similar.
Have you read the summary through the end? by Blaskowicz · 2017-03-23 08:28 · Score: 1

This is like saying a wind tunnel is useless because a stationary fan attached to the ground and blowing on a plane is a poor way to achieve air travel. But, people still use wind tunnels aplenty, to look at what happens when you blow on a airplane mock up or a wing and assess whether that design will work well in flight.
Re:How about actual sunlight instead of projectors by jfdavis668 · 2017-03-23 08:28 · Score: 1

According to the DOS barrier of thermodynamics.
Cue the sun by drew_kime · 2017-03-23 08:57 · Score: 1

https://www.youtube.com/watch?...

--
Nope, no sig
Detailed photos by zycx · 2017-03-23 09:01 · Score: 1

A local newspaper has posted some interesting photos here
Re:Useless boondoggle. by Blaskowicz · 2017-03-24 00:44 · Score: 1

That said I do share your concerns about storage and perhaps as importantly distribution. The hydrogen economy is a bunch of crap and mostly prestige projects for car and oil companies. I do not discount it entirely though because hydrogen production is useful in its own right, as a chemical feedstock (replacing hydrogen made from methane), possibly for very limited fuel uses like mining trucks, industrial heat ; basically everything except cars, general transportation, homes, laptops or what have you.
Re:To Make Hydrogen Fuel?! by LifesABeach · 2017-03-24 12:16 · Score: 1

My bad, I was thinking He3. As for the Drone? A Drone is also a type of Bee. But all irony aside. Why not go after the He3 on the surface of the moon with machines that can be controlled from Earth? Why does an investor want to build a sun when there are other methods that are field tested and cheaper? What is the pay off?