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Optical Concentrator To Make Solar Power Cheaper

Soulskill posted more than 5 years ago | from the bright-ideas dept.

Power 141

Al writes "Researchers at a company called Morgan Solar have developed a simple solar concentrator that promises to cut the cost of solar energy. The Light-Guide Solar Optic (LSO) consists of a specially-molded acrylic optic that traps light and guides it toward its center using total internal reflection. At the middle of the concentrator another optic made of glass receives the incoming light, amplifies it and directs it toward a small solar cell at the very center of the device. Unlike other concentrators, the light doesn't leave the optic before striking a solar cell so there's no air gap, and there's no chance of fragile components being knocked out of alignment. This could significantly reduce the cost of manufacturing this type of solar cell."

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first post makes you suck my dick (-1, Flamebait)

Anonymous Coward | more than 5 years ago | (#26941809)

fag

Cool (5, Interesting)

Hatta (162192) | more than 5 years ago | (#26941815)

That's actually pretty cool. By concentrating the light, they need less photovoltaic material per square foot of land used for solar. I'm curious how the efficiency of photovoltaic cells varies with the concentration of light. Will 1 square foot of sunlight concentrated into a few square inches of photovoltaic cells produce as much power as 1 square foot of unconcentrated photovoltaic cells?

Re:Cool (4, Interesting)

Skapare (16644) | more than 5 years ago | (#26941879)

The efficiency actually goes up relative to PV material in straight unmagnified sunlight. I'm sure there's a saturation point where that stops. This is one reason concentrating light on PV is a plus. Of course, the other is that it involves less PV material cost.

Re:Cool (1)

jd34 (599131) | more than 5 years ago | (#26944349)

Efficiency does go up at higher light intensity, but the fact that the device must track means that there must be more horizontal space between the collectors to avoid shading. The assertion that less land will be needed would require a dramatic improvement in efficiency to overcome the handicap of increased inter-collector spacing. Variation in light intensity usually causes problems in photovoltaic array conversion efficiency. Thus, issues such as inter-collector shading and non-uniform concentration lead to reduced overall efficiency, often by far more than the affected area. It would be nice if non-imaging concentrators could be used as they could be placed closer together in still configuration rather farther apart as the moving trackers have to be placed. However, the severe variation of intensity generated by non-imaging concentrators usually makes them impractical for photovoltaic applications. So, saving on photovoltaic material does not also mean saving on land.

Another "investor opportunity"? (3, Insightful)

Futurepower(R) (558542) | more than 5 years ago | (#26944849)

Acrylic rapidly becomes yellowed when exposed to ultraviolet, and especially under very high-intensity light, even if it has anti-yellowing chemicals added. This article, Applications and Limits of Polycarbonate and Acrylic Lenses [hubbell-canada.com] , explains "... yellowing is a sign of degradation of the plastic molecule. Heat and ultraviolet act to break the molecules. This surrenders the intrinsic strength of the material as the molecular structure no longer consists of long intertwined chains but fractured segments. This may be reflected in reduced strength of parts with formed surfaces as these surfaces tend to localize stresses."

The article, A Cheaper Solar Concentrator [technologyreview.com] , referenced in the Slashdot story says, "With a flat bottom and convex, mirrored top, the [Morgan Solar [morgansolar.com] ] optic receives the incoming barrage of light at a concentration of about 50 suns and amplifies it to nearly 1,000 suns before bending the light through a 90-degree angle."

The article does not explain how there is a concentration of 50 times before the light reaches the optics. The article is wrong in using the word "amplifies". The correct word would be "concentrates".

To have a 1,000 times concentration, the area of the optics must be 1,000 times larger than the area of the solar cell. That delivers 1,000 times the heat, also.

Morgan Solar's investors page [morgansolar.com] says, "Morgan Solar was incorporated in June 2007 and is currently well funded by a start-up investment from our angel investor and Chairman, Eric Morgan." Apparently the company was funded by the inventor or someone in his family. It says, "Our plans call for securing our next round of investment funding by Q1 2009. If you are a venture capital company or a potential partner-investor interested in exploring investment opportunities with our company, please contact us."

Was a Slashdot editor paid to allow this story? Did Slashdot profit? Was Technology Review paid to run the story? I think that articles about companies that are soliciting investments should have a statement about whether or not someone was paid.

Re:Another "investor opportunity"? (1)

RobRyland (960596) | more than 5 years ago | (#26945003)

+10 insightful -Rob

This has to be a hoax (1)

goombah99 (560566) | more than 5 years ago | (#26945605)

Optical concentration for solar cells using lenses or mirrors is of course old news. They work dandy except for the problem that the more you concentrate the more you have to track the sun's position. Tracking solar cells are an economic non-started except in certain applications.

Now classical optics says you cannot compress phase space with refractive or reflective optics. Ergo the claim being made is impossible unless they are
1) relying on non-refractive optics (e.g. scattering)
2) only gettin a boost no larger than the index of refraction of the material (i.e. immersion lenses can concetrate by a factor equal to the index of refraction as long as the absorption occurs inside the medium.

otherwise this is just back to tracking and thus useless.

Here's the link ... (4, Informative)

Skapare (16644) | more than 5 years ago | (#26941917)

... about concentrating solar power [wikipedia.org] .

Re:Cool (5, Informative)

vsage3 (718267) | more than 5 years ago | (#26942055)

That's actually pretty cool. By concentrating the light, they need less photovoltaic material per square foot of land used for solar. I'm curious how the efficiency of photovoltaic cells varies with the concentration of light

For a constant temperature, efficiency goes up logarithmically with light concentration. A solar cell with 1 sun on it is going to be less efficient than one with 500 suns on it assuming you have a way to cool the cells. Past a certain point the efficiency drops like a rock due to lack of cooling the cells and this reduces the voltage you can produce by about 2.3mV/C past room temp.

Re:Cool (2)

schwillis (1073082) | more than 5 years ago | (#26942131)

I think this could have a lot of potential for consumer level portable solar panels, all the portable panels avaible for back packing and bicycleing and whatnot are pretty crappy right now, but this would allow compact sollar devices to be a lot more feasible I think. Also you could remove the lense and use it as a fire starter.

Re:Cool (3, Interesting)

M. Baranczak (726671) | more than 5 years ago | (#26942173)

Won't work. This thing has to face the sun directly. Which means that it has to be a fixed installation, and it won't work when it's cloudy.

The article briefly mentions some other group at MIT that's developing a concentrator that works with diffuse light - so presumably that would take care of both those problems.

Re:Cool (1)

schwillis (1073082) | more than 5 years ago | (#26942885)

it would work, how complicated is it to point a solar pannel towards the sun? All the current portable compact solar panels you have to point at the sun. and I don't see why it would be anyworse then any other solar panel with it's cloudy, you can still get some power on a cloudy day if it isn't to cloudy.

Tilting is overrated (3, Insightful)

Skapare (16644) | more than 5 years ago | (#26943065)

A flat panel can be pointed at the position of the midday sun, and left stationary would have a reduced aperture to the sun as a result of the angle in the morning and evening. Turning the whole assembly helps. But, if there are many panels, they would have to be spread out or else some will shadow parts of others. Basically, it comes down to capture area. If you have a 10 meter by 10 meter area, there's only so much sun that enters it. In the morning and evening, there is less sun entering that area because of the angle. If you have one giant 10m by 10m panel that in there that gets tilted, its shadow will be outside the area, and you're actually capturing sun that would go outside. If you are have lots of small 100cm x 100cm panels, tilting them doesn't help because of the shadows. Remember, there's less total sunlight to get at an angle. Tilting is only an advantage when you have less than 100% coverage, and are willing to lose sun at midday.

Tilting is also a mechanical thing which means some kind of control mechanism, more exposure to failure, and greater maintenance costs.

An optical structure that would funnel light from any angle over a reasonably wide angle range would be the ideal solution. It would handle the change from morning to midday to evening, and would handle the diffuse light of cloudy weather. That's the thing to work on.

Re:Cool (0)

Anonymous Coward | more than 5 years ago | (#26942803)

Why is this modded funny?

Re:Cool (1)

The Master Control P (655590) | more than 5 years ago | (#26943167)

Increased light concentration means increased efficiency, though it levels off past a certain point. Whenever you see those "most efficient solar cell yet" stories, that was the cell's performance under about 1000x the light level of the sun.

So you'll actually get a bit more power by concentrating, but there's a flip side - the heat. Solar cells are semiconductors, and semiconductors hate high temperatures.

Re:Cool (1)

duffel (779835) | more than 5 years ago | (#26945277)

More, actually... solar cells can actually increase in efficiency at higher concentration.

This is part of the main attraction of 3rd generation solar cells, such as multijunction, quantum well or intermediate band cells, which are expensive to make but very very efficient, especially at high concentrations.

Incidentally, there are some companies that already use non-imaging optics as part of their concentrator system, SolFocus [solfocus.com] being one of them.

Not an original idea? (1)

kheldan (1460303) | more than 5 years ago | (#26941823)

Haven't they been using things like this for decades? Sure, it works, but I don't think it's an original concept, is it?

Re:Not an original idea? (4, Informative)

Yetihehe (971185) | more than 5 years ago | (#26941871)

The original concept here is flat fiberoptics-like lens, so you can transport more concentrators in the same space and there will be no misalignment during assembly, because small pv cell is glued onto back of these lens, not held at a distance.

Very original idea (2, Insightful)

zrq (794138) | more than 5 years ago | (#26942133)

.. At the middle of the concentrator another optic made of glass receives the incoming light, amplifies it and directs it toward a small solar cell.

Amplifying light with a glass 'optic' would be quite original. Concentrating it yes, but amplifying it?
I would be very impressed if they have actually achieved it.

Re:Very original idea (1)

markov_chain (202465) | more than 5 years ago | (#26943107)

What the heck is an "optic?"

Re:Very original idea (1)

Malekin (1079147) | more than 5 years ago | (#26943393)

Amplifying light with a glass 'optic' would be quite original.

Optical fibre amplifiers use a length of erbium-doped glass as the amplification medium. They were invented in the 80s and are used around the world. An external source excites the erbium and as the signal to be amplified comes in it stimulates emission. The result is a signal coming out brighter than the one that went in.

http://en.wikipedia.org/wiki/Optical_amplifier [wikipedia.org]

Of course, it'd be daft to use one in this application as while they do amplify, it's not like they're >100% efficient.

No, not really (1)

rs79 (71822) | more than 5 years ago | (#26944717)

I have a $9.99 solar powered battery charger from Crappy Tire that charges 4 NiMH AA's in about 3 days. It has a little watt meter thingamajig on it that shows watts or rather, the amount of energy being pushed back into the batteries. It takes about 3 days to charge them.

By using a couple of bits of broken mirrors on either side of this gizmo, increasing the amount of light hitting the solar cell, the needle on the watt-o-meter is pegged and the batteries charge in one day instead of three.

So no, the idea of concentrating light to improve the efficacy of solar cells isn't new, just this way of packaging them is. And it's clever.

neat idea. What do they do with the heat though? (4, Interesting)

Almost-Retired (637760) | more than 5 years ago | (#26941885)

Neat idea, but how do they get rid of the heat of 1000 suns? Does the IR escape because it isn't reflected the same way?

Re:neat idea. What do they do with the heat though (2, Interesting)

Colonel Korn (1258968) | more than 5 years ago | (#26942081)

Neat idea, but how do they get rid of the heat of 1000 suns? Does the IR escape because it isn't reflected the same way?

About 80% of the energy is absorbed across the entire solar spectrum. Yes, it will radiate some heat away as IR, but mostly the heat is convected away by the surrounded air. You're right, though--this is a design concern for these devices, as temperature effects efficiency and lifetime.

Re:neat idea. What do they do with the heat though (1, Informative)

Anonymous Coward | more than 5 years ago | (#26943171)

If it effected efficiency and lifetime, the situation would be pretty positive.

What you mean is that it affects efficiency and lifetime.

Re:neat idea. What do they do with the heat though (0)

Anonymous Coward | more than 5 years ago | (#26945529)

Isn't heat a form of energy? There must be a way to convert it to electricity.

Re:neat idea. What do they do with the heat though (4, Interesting)

mh1997 (1065630) | more than 5 years ago | (#26942107)

Neat idea, but how do they get rid of the heat of 1000 suns?

They keep them in the dark so they don't get hot.

or from wikipedia:

The solar cells require high-capacity heat sinks to prevent thermal destruction and to manage temperature related performance losses...In May 2008, IBM demonstrated a prototype CPV using computer chip cooling techniques to achieve an energy density of 2300 suns.

Re:neat idea. What do they do with the heat though (1)

M. Baranczak (726671) | more than 5 years ago | (#26942233)

My first thought was, why are they using a PV cell in the first place, instead of using the heat to drive a turbine?

Re:neat idea. What do they do with the heat though (1)

Sethumme (1313479) | more than 5 years ago | (#26942567)

At some point, they'll come up with a good system that uses PV cells to collect light and use the excess thermal energy to drive a turbine.

Re:neat idea. What do they do with the heat though (2)

Captain Hook (923766) | more than 5 years ago | (#26942989)

or a stirling engine.

Re:neat idea. What do they do with the heat though (2, Insightful)

HornWumpus (783565) | more than 5 years ago | (#26943113)

Heat water with the waste heat.

When the water tank gets too hot you heat the house with it (or dump the heat outside).

I'd use an oil loop between the collectors and an over-sized water tank.

Re:neat idea. What do they do with the heat though (1)

MichaelSmith (789609) | more than 5 years ago | (#26943805)

In the places where you would install a solar power plant hot water is probably not a rare commodity.

waste heat (4, Interesting)

zogger (617870) | more than 5 years ago | (#26942661)

Or use the waste heat to drive a stirling engine as a booster perhaps. I know just regular solar panels get wicked hot on the backs of them when sitting in full direct sun, I mean it is black stuff sitting behind a clear surface and stuck on a metal backing, it gets *hot*. Just doubling that heat would turn it into some sort of decent viable optional energy source.

And why PV? Instant electricity from it, solid state, no moving parts, pretty spiffy stuff. Big solar concentrators with turbines are cool too, we have those for giant megawatt scale production now, but we don't have them for joe homeowner yet or joe back packer, PV fits the bill for those purposes.

Re:waste heat (1)

evanbd (210358) | more than 5 years ago | (#26944593)

Nope, you don't want to use that waste heat. If you insert a thermal engine in the waste heat path, then for equivalent cooling capacity the solar cell gets hotter. At higher temperatures the efficiency of the solar cell drops rapidly. Since the temperature is low (by heat engine standards) the efficiency of your heat engine will suck anyway; you're better off spending your heat-moving ability keeping the solar panel cool than putting the waste heat to use.

Short version: heat engines efficient enough to be interesting need to be hot; solar cells don't like that. Just cool the solar cell and boost efficiency directly.

I still think you could use the heat (1)

zogger (617870) | more than 5 years ago | (#26945099)

I'm fully aware about how PV degrades with temperature rise, I own some solar PV and use it (since 99 actually), I just noticed a long time ago the backs get really hot. I haven't done it yet but I think you might be able to integrate a built in fluid radiator to the backs of them and remove heat that way and use it for hot water or additional space heating perhaps. Or something, that's the thing, you are gathering it, it is waste, it needs to be removed, so why not figure out what useful purpose it could be put to? Maybe as a preheater to a solar still, to make the distilled water for the battery bank? I don't know, but *something* can be done with it. As soon as I have the scratch for a "spare" one I wanted to try some experimentation on it, as it is now I don't want to chance destroying a multi hundred dollar PV panel, and I don't want to experiment on some cheap little bitty hardly useful one, I want something that is actually worthwhile to use and would give me real world results.

Just another one of those projects for the future, add it to the list.....heh, ya never run out of projects!

CHAPS (1)

BeaverCleaver (673164) | more than 5 years ago | (#26945271)

There's a system being deployed in Australia called Combined Heat And Power (CHAPS), that uses curved mirrors to focus the sun onto what is essentially a pipe covered in photovoltaic cells. The PVs convert some of the energy into electricity and are cooled by water flowing thru the pipe, which then feeds the hot-water system of the building they're mounted on. Total claimed efficiency is up to 60%. The system is currently installed ont he roof of one wing of Bruce Hall, a residential college at the ANU.

Linkies:
http://solar.anu.edu.au/projects/chaps_proj.php [anu.edu.au]
http://abc-webdesign.com.au/examples/solar/pages/chaps.html [abc-webdesign.com.au]

Re:neat idea. What do they do with the heat though (1)

UttBuggly (871776) | more than 5 years ago | (#26942783)

Neat idea, but how do they get rid of the heat of 1000 suns? Does the IR escape because it isn't reflected the same way?

I would throw out the idea of a "Tri-brid" power solution.

1) Solar arrays using a design like the article.

2) Steam plant, using the heat byproduct of the arrays.

3) Wind turbines, married to the distribution system with the first two.

My thoughts on this were concerning the land use efficiency. The Southwest U.S. is ideal for all three in many areas. By co-locating and combining the technologies, you get a near 100% output cycle, assuming you don't get the magic trifecta of no sun, no wind, and insufficient IR through clouds to kill any heat input to the steam system on a regular basis.

Design and unit placement would be critical to success, but this is easily doable. Plus you upgrade as needed without losing all of the output during conversion to newer turbine blades or even more efficient PV cells, optics, and so on.

I sent this to T. Boone Pickens' wind power site, urging them to consider high-efficiency solar arrays at the wind turbine installations, where feasible. I've since thought about the waste heat component on the solar arrays, and now think some design consideration should be done about adding that to squeeze out some more juice.

I'd truly like the folks here to blast holes and/or offer suggestions to improve, augment, or modify a CETOS (Combined Energy Technology Output System) like I've described.

Feel free to rename it as well!

So, that's a REAL long answer to what to do with the heat!

Re:neat idea. What do they do with the heat though (1)

ductonius (705942) | more than 5 years ago | (#26943201)

2) Steam plant, using the heat byproduct of the arrays.

The efficiency of heat engines is governed by the temperature difference between the hot and cold side. Coal and nuclear plants typically have a hot side at around 600 degrees Celsius and newer designs are pushing that higher for greater efficiency. Common glass stats to soften at around 550 degrees Celsius and solar cells start to lose efficiency even at 50C.

The solar array and concentrator would have to maintain a temperature well below 600C just to avoid melting, so any heat engine run from their waste heat would be inefficient.

This is, of course, just the same problem solar has had all along: It's just not efficient enough to compete with other power sources. Coupling inefficient heat engines to inefficient solar arrays only increases the extracted-energy density of the land, not efficiency.

By co-locating and combining the technologies, you get a near 100% output cycle, assuming you don't get the magic trifecta of no sun, no wind, and insufficient IR through clouds to kill any heat input to the steam system on a regular basis.

That trifecta would only require no wind and nightfall, so it would probably happen quite a lot. The low energy density of the IR radiating from the upper atmosphere makes collecting it inefficient. Coupling widnfarms to even out production also has the problem of transmission loss.

Wind, solar, geothermal and hydro are all good supplements where they work, but there's really no substitute for traditional power plants. There are really only two choices for power production today: coal and nuclear. It's either one or the other.

Re:neat idea. What do they do with the heat though (1)

MichaelSmith (789609) | more than 5 years ago | (#26943793)

I saw a system recently which massively concentrates sunlight onto high efficiency PV cells, which are actively cooled, I think by a mixture of gas and liquid coolant. In other words they are cooled like any other type of engine.

Re:neat idea. What do they do with the heat though (1)

rs79 (71822) | more than 5 years ago | (#26944759)

" Neat idea, but how do they get rid of the heat of 1000 suns? Does the IR escape because it isn't reflected the same way?"

(Looks outside at the grim February bleakness laughingly referred to as "winter")

I can not answer your question. But as a Canadian I have some suggestions as to where you might send some extra heat.

Re:neat idea. What do they do with the heat though (1)

noidentity (188756) | more than 5 years ago | (#26944835)

Yes, we need a way to get rid of all that heat. After all, heat is the last thing we need when generating electricity; just look at any typical conventional electric generator plant .

Re:neat idea. What do they do with the heat though (1)

duffel (779835) | more than 5 years ago | (#26945303)

Well, if you attach your solar cell to a heat sink the same size as the concentrating surface (lens), then you have as much area to dissipate heat over as you have for a normal, non-concentrating panel.

In other words, the ratio of light collecting area to heat emitting area is the same in both cases.

Could be useful for smaller devices (1)

virtualnz (1187667) | more than 5 years ago | (#26941887)

This would be great for smaller devices, like mobile handsets because there would be smaller surface area required. I like the idea of walking around with an iPhone for a few days without having to charge it if I'm not near a PC or laptop.

It's just a fresnel lens (4, Interesting)

Matt Perry (793115) | more than 5 years ago | (#26941893)

From the picture, it looks a lot like a fresnel lens [wikipedia.org] .

Re:It's just a fresnel lens (3, Interesting)

Rowanyote (980640) | more than 5 years ago | (#26942051)

There are some key differences. In a fresnel lense the ridges just bend the light passing through a small amount. It is basically the surface of a regular lense stepped into a flat surface. Thus it acts almost exactly like a standard lense and has a focal point somewhere behind that all the light is reflected to.

From the sound of it, this lens bends all the incoming light 90 degress or more, sending it towards the center through the lens itself to a secondary optic area which concentrates the light and reflects it all out of the center with a focal length of effectively zero.

Re:It's just a fresnel lens (0)

Anonymous Coward | more than 5 years ago | (#26942059)

The picture looks like a fresnel lens, though the description sounds like a Winston cone. (They even quote Winston in the article).

Re:It's just a fresnel lens (2, Informative)

KibibyteBrain (1455987) | more than 5 years ago | (#26942235)

The one thing I learned about about optics from the elective class I took in college: all lenses look similar, but function very very differently. To evaluate a lens based on how it looks is something like evaluating a microprocessor based on how the die looks.

Re:It's just a fresnel lens (0)

Anonymous Coward | more than 5 years ago | (#26943239)

To evaluate a lens based on how it looks is something like evaluating a microprocessor based on how the die looks.

Sometimes the microprocessor die knows things [about.com] .

Re:It's just a fresnel lens (4, Informative)

EndoplasmicRidiculus (1181061) | more than 5 years ago | (#26944125)

It's not a fresnel lens. The light is reflected internally and concentrated towards the center rather than being refracted towards a focal point some distance away. As always, pictures speak louder than words: http://www.morgansolar.com/images/technology/lgophoto1_full.jpg [morgansolar.com]

solex agitator (1, Informative)

ByTor-2112 (313205) | more than 5 years ago | (#26941921)

Watch out for the man with the golden gun...

Re:solex agitator (1)

Gerald (9696) | more than 5 years ago | (#26943149)

He's too busy fighting jedis now.

Huh? (0)

Anonymous Coward | more than 5 years ago | (#26941927)

It concentrates the light, increasing the intensity over a smaller area. I don't see where amplification (creating more light) is involved at all.

Re:Huh? (1)

zerosomething (1353609) | more than 5 years ago | (#26942003)

Exactly. Is it too much for the science reporter to be required to have taken a couple of science classes? This is basic stuff they should know.

Re:Huh? (1)

M. Baranczak (726671) | more than 5 years ago | (#26942293)

A science reporter at a magazine published by MIT? Yeah, I guess it is asking too much.

Planetfall (0)

Anonymous Coward | more than 5 years ago | (#26941949)

And when at last it is time for the transition from megacorporation to planetary government, from entrepreneur to emperor, it is then that the true genius of our strategy shall become apparent, for energy is the lifeblood of this society and when the chips are down he who controls the energy supply controls Planet. In former times the energy monopoly was called "The Power Company"; we intend to give this name an entirely new meaning.

        * CEO Nwabudike Morgan "The Centauri Monopoly"

does it require batteries to amplify the light? (0)

Anonymous Coward | more than 5 years ago | (#26941973)

well, does it?

btw, btdt. i believe the name, Ames, is attached to the prior art. it was never commercialised because it was "too hard" to produce at the time.

Does this have to be aimed? (1)

Animats (122034) | more than 5 years ago | (#26942007)

Does this thing have to be aimed at the sun? In 1D or 2D? If it needs 2 pointing axes, it's too complex. 1D, maybe; there are trough-like concentrators at Mojave which are driven to move with the sun.

Re:Does this have to be aimed? (1)

John Hasler (414242) | more than 5 years ago | (#26942349)

It would appear that it must track the sun precisely.

Re:Does this have to be aimed? (1)

M. Baranczak (726671) | more than 5 years ago | (#26942409)

Why does that make it "too complex"? Finding the sun is not a particularly hard engineering problem.

Burn, burn your little b*%^&rds & solar sm (2, Funny)

Rowanyote (980640) | more than 5 years ago | (#26942011)

My house has an nearly unbeatable infestation of small ants, and I can't help but think just what a magnificent burning lens one of these would make minus the solar chip.

But aside from that, there are some other pretty nifty uses for concentrated sunlight. I am definitely curious whether the lens can be scaled up to a square meter or more, enough to possibly melt glass or aluminum.

Re:Burn, burn your little b*%^&rds & solar (1)

polar red (215081) | more than 5 years ago | (#26942075)

I am definitely curious whether the lens can be scaled up to a square

You're thinking of solar furnaces, like the one in Odeillo http://en.wikipedia.org/wiki/Solar_furnace [wikipedia.org] (already in production for over 20 years ...)

Re:Burn, burn your little b*%^&rds & solar (0)

Anonymous Coward | more than 5 years ago | (#26942489)

Sounds like sugar ants... your exterminator will have ample methods of dealing with those, or read up on it yourself:

http://www.google.com/search?hl=en&q=sugar%20ants&btnI=I'm+Feeling+Lucky&aq=f&oq= [google.com]

The sugar ants here are real suckers for the bait, it works like magic.

Re:Burn, burn your little b*%^&rds & solar (1)

drinkypoo (153816) | more than 5 years ago | (#26943683)

you can already buy big huge fresnel lenses cheap and then use an array of them to do all kinds of solar concentration.

transmission lines (4, Interesting)

bcrowell (177657) | more than 5 years ago | (#26942021)

I live in LA. To the east of us is the Mojave Desert, and there's already quite a bit of solar power out there right now [wikipedia.org] . The big issue is transmission lines to get the energy from the Mojave to LA. Building transmission lines requires political action, and that's slow and uncertain because of NIMBY. I have photovoltaics on my roof, but objectively, if you look at the price of land where I live versus the price of land in the Mojave Desert, it's pretty clear where you should be building these things.

Shadow lines (1)

Ostracus (1354233) | more than 5 years ago | (#26942115)

That's the thing about alternatives. Storage. Also unlike wind solar panels block the ground underneath big time. One has to wonder about the effect if solar becomes a bigger source.

Re:Shadow lines (1)

Maxo-Texas (864189) | more than 5 years ago | (#26942187)

I'm thinking effects similar to forest.

Shade, cooler, a little less evaporation, only shade tolerant bushes underneath.

Of course you don't want plants overgrowing your solar power plant anyway.

Re:Shadow lines (3, Interesting)

WalksOnDirt (704461) | more than 5 years ago | (#26942799)

Of course you don't want plants overgrowing your solar power plant anyway.

Which is why in actual practice the land under the solar collectors is made as sterile as they can afford to make it. We need to accept that getting most of our energy from desert solar will probably require destroying the ecology of several percent of the deserts of the southwest. I think that's an acceptable trade off, but for those who insist on a "greener" solution I suggest they push for nuclear power.

Re:Shadow lines (1)

duffel (779835) | more than 5 years ago | (#26945377)

OK, several things:

There is not enough fissile material in the world to supply the world with nuclear power.
Nuclear power is far from green. Consider the waste for one. The effort of mining it.
Normal power plants tend to make the area under the power plants *completely* unusable... I mean, check out all those buildings in the way.

Do you really think that solar power use in a desert will have a more pronounced impact on the environment than using, oh, i don't know, coal power in the rest of the country? Because that's the alternative. Nuclear power plants are cool and useful, but if you do the maths they're not actually as green as you want them to be.

Re:Shadow lines (1)

jackbird (721605) | more than 5 years ago | (#26945437)

1. Depends how you do it. Thorium and pebble beds being two of the ways to have enough fuel for millennia. 2. Depends how you do it. If you're reprocessing almost all your waste and only have to dispose of a small amount of hot (industrially useful) stuff for a couple of hundred years, it's not so bad. 3. Yes, but since the OP was talking about single-digit percentages of the entire southwestern desert, the footprint of a nuclear plant or fifty is going to be a lot smaller.

Re:Shadow lines (1)

dbIII (701233) | more than 5 years ago | (#26945475)

desert solar will probably require destroying the ecology

By putting in a road, power lines and some things that shade the ground a bit in a couple of square miles for a huge installation? I don't think you quite understand what you are talking about.

but for those who insist on a "greener" solution I suggest they push for nuclear power.

The nuclear debate is effectively dead in the USA until you can find people that will put up vast amounts of money to build things that will not produce anything for a decade and even then are not economicly viable unless there is a large requirement for weapons materials. Unfortunately solar thermal (despite requiring smaller unit sizes to break even) is in the same boat. The peaks are the important thing anyway, so a few photovoltaics may do the job in certain places and times. Massive numbers of them are just silly so you will not see the nuclear lobby's strawman of an entire state covered in the things. At a cetain scale solar thermal becomes a huge amount cheaper per MW.

Just think of these as another thing in the toolkit of gadgets and avoid the "one true power" bullshit that should only come from dishonest salesfolk (eg. nuclear lobby).

Re:Shadow lines (1)

Belial6 (794905) | more than 5 years ago | (#26942251)

I'm thinking it will turn that 30 year roof into a 40 year roof, or that 20 year road into a 30 year road. Maybe extend the life of a parking lot or two....

Re:Shadow lines (3, Interesting)

bcrowell (177657) | more than 5 years ago | (#26942281)

That's the thing about alternatives. Storage.

Huh? My post, which you were replying to, didn't say anything about storage.

LA's problem with lack of capacity shows up on hot days in the summer, when everyone is running their air conditioner. That's exactly when the Mojave plants will be running at their maximum production. Because of this excellent match between peak production and peak demand, there isn't really an issue with storage. It's a perfect fit.

Re:Shadow lines (1)

duffel (779835) | more than 5 years ago | (#26945321)

Storage isn't that big a deal until we collect so much solar power that we can't use it up during the day.

During the day there are massive drains of power because of things like air conditioning or just industrial use that you don't have to worry about storing solar power until you make more than is needed by all those processes.

Re:Shadow lines (1)

duffel (779835) | more than 5 years ago | (#26945345)

Well, given that the solar constant is 1 kW per square meter, multiply by efficiency, you can work out just what sort of area you need to cover to supply any given site with solar power - and you'll find that barely any of the united states will have to be covered with solar cells. One or two deserts will do.

Re:transmission lines (-1, Troll)

Anonymous Coward | more than 5 years ago | (#26942123)

Well if you all in California would ship the illegal alliens parasites back to the turd world, there would be:
  • More room for power lines.
  • A state budget surplus.
  • Way lower taxes.
  • Half the demand on the power grid.
  • A cleaner environment all around.

It's a win for everyone, no matter which way you slice it.

Re:transmission lines (1)

FooAtWFU (699187) | more than 5 years ago | (#26942515)

You're probably not going to be building lens-concentrated photovoltaics in the Mojave. Some sort of solar concentrator design (with the big tower in the middle that they aim the sun at with mirrors) or the more-experimental solar chimney designs are better bets and generally much more cost-effective.

Wow, just in time (2, Funny)

Anonymous Coward | more than 5 years ago | (#26942067)

This should arrive just in time to recharge my flying car. I can hardly wait!

I object to the word "amplify". (4, Insightful)

Jane Q. Public (1010737) | more than 5 years ago | (#26942079)

It's TFA's fault, but even so.

There is no "amplification" taking place at all, merely concentration. Those are two VERY different things.

Re:I object to the word "amplify". (0)

Anonymous Coward | more than 5 years ago | (#26942217)

With enough amplification, we can run them solar panels in the darkness of our mothers' basements!

Hell, one could generate power for all computing equipment, just by capturing the stray light from the lcd panel. For maximum efficiency, just glue the panels together.
Now, imagine a beowulf cluster of those?

I'd say their research is right on track!

Re:I object to the word "amplify". (1)

dangitman (862676) | more than 5 years ago | (#26944639)

Yeah, I've always hated that word.

An unstated benefit (2, Interesting)

vandelais (164490) | more than 5 years ago | (#26942113)

of this particular solar advance means not only greater efficiency and lower cost, but also MUCH MUCH greater feasability for wider adoption by areas of higher latitudes. In addition, this particular advance would appear to reduce the detriment of partial occlusion by some factor.

This concentrator technology also reduces the manufacturing use of rare metals for these systems and that is another huge benefit also.

Concentration is not amplification (1)

icebike (68054) | more than 5 years ago | (#26942139)

> optic made of glass receives the incoming light, amplifies it

I'm sorry, but an "optic made of glass" can not amplify light. All it can do is concentrate it.

In fact the whole this just sounds like packaging a solar cell and an elaborate magnifying glass to me.

No net decrease in surface area. No proven increase in efficiency.

Re:Concentration is not amplification (2, Informative)

pete-classic (75983) | more than 5 years ago | (#26942221)

No net decrease in surface area. No proven increase in efficiency.

There's a third axis; cost per watt. Acrylic is cheaper than PV silicon.

(Actually the relationship of surface area and efficiency is fixed, so it's really a second axis.)

-Peter

Can you put it in place of glass windows? (1)

wisebabo (638845) | more than 5 years ago | (#26942167)

If this material concentrates all of the sunlight onto the PV chip in the center does that mean that NO OTHER light will pass through it? From the description of something that will take (sun)light from any angle and direct it towards the center does that mean someone behind it will only see black?

If not, it might be a good surface to use on the millions and millions of square feet of windows that covers office buildings. You could conceivably generate ALL of a buildings energy needs that way. (The power generated would also be in good correlation with needs, hot day requiring air conditioning would often come with bright sunlight). Admittedly, the fresnel (like) lens might distort the view so much that you can't see anything recognizable outside but having a translucent like screen to the outside could be a lot less claustrophobic than a blank wall.

Re:Can you put it in place of glass windows? (2, Funny)

thrillseeker (518224) | more than 5 years ago | (#26942313)

does that mean someone behind it will only see black?

Caution ... do not look into solar concentrator with remaining eye.

Cf. holographic concentrators (1)

5pp000 (873881) | more than 5 years ago | (#26942183)

Interesting to compare this to a holographic concentrator [prismsolar.com] . This optical concentrator has a much higher concentration ratio and thus allows the use of much less silicon, but on the other hand it requires a mechanical tracker and a heat sink, which the holographic concentrator does not.

I hope to see both these technologies in production soon. $/W is the big barrier for photovoltaics.

"Cheaper" Power Cells (2, Interesting)

Mishotaki (957104) | more than 5 years ago | (#26942199)

There has been so many news about breakthrough in power cells technology... making them cheaper and more efficient... but why the hell are they still so damned expensive?

Re:"Cheaper" Power Cells (5, Insightful)

John Hasler (414242) | more than 5 years ago | (#26942397)

Because they used to be insanely, ridiculously, incredibly damned expensive. Now they are merely damned expensive. In a decade or so they will be down to expensive. Someday they will be cheap, but the sun may go out first.

Re:"Cheaper" Power Cells (1)

Spy der Mann (805235) | more than 5 years ago | (#26942717)

Someday they will be cheap, but the sun may go out first.

Hmmm I can see the ads.
"Purchase Duke Nukem Forever now, and get a free pack of solar cells!"

Re:"Cheaper" Power Cells (0)

Anonymous Coward | more than 5 years ago | (#26942971)

Nope,
By that time we've spend all our precious rare metals. (while destroying some African nations in the process)

They've just re-discovered (1)

kilodelta (843627) | more than 5 years ago | (#26942269)

In other words, a Fresnel lens. Nice!

Re:They've just re-discovered (3, Informative)

PPH (736903) | more than 5 years ago | (#26942421)

Not really a lens of any type. Its an example of non imaging optics [wikipedia.org] . A lens, Fresnel or otherwise, or a mirror, produces an image of an object at its focus. So, as the sun moves across the sky, its image would move across the plane of focus. So you'd either have to make that image plane big enough to contain the imaged sun track over a day or move the apparatus. Non imaging optics reflect or refract incoming light rays from any direction on to a single point as well as focus the light from a large aperture onto a smaller area.

While the idea of non imaging optics in general isn't novel, the design of this device might be.

Wait... (1)

Quiet_Desperation (858215) | more than 5 years ago | (#26942393)

Didn't Joe DuBois invent this on Medium last season?

Re:Wait... (1)

Brickwall (985910) | more than 5 years ago | (#26944931)

That's what I thought as soon as I RTFA. So, it must be true. Life imitates art!

there's efficiency, and then there's efficiency... (0)

Anonymous Coward | more than 5 years ago | (#26942609)

if you increase the "efficiency" by 3% while doubling the size, is that really "more efficient"? Isn't that just collecting more photons?

There seems to be one limitation (1)

Kupfernigk (1190345) | more than 5 years ago | (#26942955)

This is dependent on unobstructed sunlight and a properly aligned receptor. Which means tracking systems, which add cost. Perhaps at some point thin film PV will simply become cheaper than the lens system, because although a bigger total area will be needed, tracking will be a lot simpler or unnecessary.

Plastics make Problems (2, Insightful)

drinkypoo (153816) | more than 5 years ago | (#26943725)

The plastic is the problem. Can't we do it with all glass? If you use a solar furnace you can make it with solar energy. Alternately, if you get enough PV, you can run an electric furnace. Either way, plastic is nasty and sand is everywhere. (Some of the additives in glass are nasty, to be fair. But not all glass is nasty. All plastic is either nasty or has a short life when exposed to UV. Much is nasty AND has a short life.

Pretty fancy words (1)

nurb432 (527695) | more than 5 years ago | (#26943777)

For a simple lens...

The cost is impressive ... (1)

ScrewMaster (602015) | more than 5 years ago | (#26944661)

Well, if this outfit truly manages to achieve that one dollar per watt figure, it will cause something of a revolution in solar applications. Furthermore, if they can do a buck a watt, odds are that with increased production they can do much, much better.

If an investment of ten grand can buy me ten kW's worth of solar panels (not counting ancillary physical plant and energy storage) I'd consider putting up a small solar farm. Hell, forget the storage system: just buy a synchronized inverter and feed it back into the grid. Let the power company buy it from you.
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