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New Solar Panel Design Traps More Light

CowboyNeal posted more than 7 years ago | from the thousand-points-of-light dept.

Power 334

GoSun wrote in with an article about new solar panels that opens, "Sunlight has never really caught fire as a power source, mostly because generating electricity with solar cells is more expensive and less efficient than some conventional sources. But a new solar panel unveiled this month by the Georgia Tech Research Institute hopes to brighten the future of the energy source." The new panels are able to produce sixty times the current of traditional models.

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brighten up? (4, Funny)

Anonymous Coward | more than 7 years ago | (#18713499)

you don't want it bright, if it reflects light that's unused energy!
you want a dim future

Sweet. (1)

Eddi3 (1046882) | more than 7 years ago | (#18713501)

It's good to know that solar power is really getting off it's feet.

Re:Sweet. (0)

Anonymous Coward | more than 7 years ago | (#18714581)

Thank you for that valuable comment.

60 times the current ... (5, Funny)

Anonymous Coward | more than 7 years ago | (#18713503)

60 times the current, at 1/60th of the voltage. They're working hard to achieve the next milestone which is 100 times the current (at 1/100th voltage) before Xmas ... in space.

Re:60 times the current ... (1)

UbuntuDupe (970646) | more than 7 years ago | (#18713853)

Then maybe I can use it to power my infinite miles-per-gallon-of-gasoline car!

Catching Fire (5, Funny)

Anonymous Coward | more than 7 years ago | (#18713505)

Sunlight has never really caught fire as a power source

Well, I always saw that as a good thing, I don't know about everyone else here...

Re:Catching Fire (4, Funny)

wwrmn (42399) | more than 7 years ago | (#18714195)

AC, your parents really should have exposed you to the magic of magnifying glass.

Insects FEARED me... Mueyhahahahaha...

*yawn* (4, Informative)

Spazntwich (208070) | more than 7 years ago | (#18713509)

From TFA:

But current is only half the equation. To generate electricity, a cell has to churn out voltage as well.

And so far, that's where Ready's invention has fallen short. There's still too much resistance within the cell to produce the type of electricity that's needed. But he said he'll now focus on reworking the interface to smooth out the kinks.

This is non-news. Multi-layered cells have been talked about forever, and haven't they all previously run into similar issues?

(*yawn*)* (5, Funny)

Anonymous Coward | more than 7 years ago | (#18713575)

Yawn. Posting about how a supposed innovation is actually several years old has been done before. Didn't we just read a post titled *yawn* yesterday?

just need to tweak it some more (0)

Anonymous Coward | more than 7 years ago | (#18713539)

File under: Federal government grants.

Hey, I paid for all the other ones, why not this one.

Better then 5x improvement not possible.... (0, Informative)

Anonymous Coward | more than 7 years ago | (#18713541)

"...produce sixty times the current of traditional models" BS!!

Current solar cells are ~20% efficient... you can't do better then 100% obviously.

Re:Better then 5x improvement not possible.... (5, Insightful)

Romancer (19668) | more than 7 years ago | (#18713717)

You're talking about two different types of measurements for solar cells.

The statement "60x the current" has almost no relation to the maximum theoretical conversion of sunlight efficiency. It completely leaves out the voltage problems inherrant in these 3d designs. The total output measured in watts or VA would be somehwat more comparable to your "20 percent efficient".

Learn some math before you post.

Re:Better then 5x improvement not possible.... (2)

WalksOnDirt (704461) | more than 7 years ago | (#18714671)

What is the point of even talking about sixty times the current? In a short article with little technical detail, and no mention of efficiency, this only seems to like an attempt to mislead people into thinking something important has been accomplished.

Re:Bad math.. (4, Informative)

Technician (215283) | more than 7 years ago | (#18714363)

Current solar cells are ~20% efficient... you can't do better then 100% obviously.

Nobody claimed they produced 60 X the power. In DC circuits Volts X Amps = Watts. 60 times the current does not equal 60 times the power if the voltage is not the same. The article is very clear, the voltage is way down. They make no power claims. It's even implied that the voltage is near zero. These panels may be less effecient than the curent generation. They are working on raising the voltage. Good luck and I hope they come out with some power figures soon.

Quite a bit more than 20% (3, Informative)

laing (303349) | more than 7 years ago | (#18714473)

Spectrolab [spectrolab.com] has cells that are over 40% efficient. See here [spectrolab.com] for more details.

JSL

Efficiency is not really important (5, Insightful)

EmbeddedJanitor (597831) | more than 7 years ago | (#18713545)

The power convesion ratio is not really that important in itself. The only really important measure is $/watt.

If you can get low $/watts with low efficiency that would be OK. Tile your house with the stuff, use it as the external covering for buildings.

That is one of the major problems with PV showcases like the Australian solar race. they push efficiency more than $/watts which is my the winning cars cost hundreds of thousands of dollars.

ATTN: SWITCHEURS! (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18713835)

If you don't know what Cmd-Shift-1 and Cmd-Shift-2 are for, GTFO.
If you think Firefox is a decent Mac application, GTFO.
If you're still looking for the "maximize" button, GTFO.
If the name "Clarus" means nothing to you, GTFO.

Bandwagon jumpers are not welcome among real Mac users [atspace.com] . Keep your filthy PC fingers to yourself.

Re:ATTN: SWITCHEURS! (1, Insightful)

Anonymous Coward | more than 7 years ago | (#18714577)

Can you get some more & better pics? Less emo losers and more hot chicks please.

Re:ATTN: SWITCHEURS! (-1, Redundant)

Anonymous Coward | more than 7 years ago | (#18714653)

If the switchtroll could get them to flash some titties, that would convince me to never use an Apple again.

Re:Efficiency is not really important (0)

Anonymous Coward | more than 7 years ago | (#18714079)

Can you please explain to me your reasoning? What's the difference between using a solar chip that is 2x as efficient, and thus requiring half the material or something that requires 2x the material and is half the cost?

Re:Efficiency is not really important (1, Informative)

dhasenan (758719) | more than 7 years ago | (#18714155)

What if it were a quarter the price and half as efficient? Then you'd pay half as much to get a certain amount of power, but it would take twice as much material.

Again, learn basic math.

Re:Efficiency is not really important (2, Informative)

ZorbaTHut (126196) | more than 7 years ago | (#18714163)

None, really. However, the problem is that right now we're looking at cells which are more like twice as efficient, half the material, and ten times the cost.

Both of your examples would have the same $/watt ratio, and yes, they're equivalent in that sense.

Re:Efficiency is not really important (4, Insightful)

EmbeddedJanitor (597831) | more than 7 years ago | (#18714279)

The important practical measure is $/W. There are many ways this might be impoved and improved efficiency is one of those - potentially. What I say is that efficiency improvements that improve $/W are important and those that don't are not (or very much less important).

Many improvements in efficiency are through more expensive processing etc resulting in more expensive PV. The World Solar Race favours the team with the best efficiency, even if that costs hundreds of thousands of dollars. Much of the PV research is geared towards efficiency and this is the measure by which they compete (eg. http://www.boeing.com/ids/news/2006/q4/061206b_nr. html [boeing.com] ).

This focus is detremental from a practical position of solving the energy crisis. While the big research dollars are focussed on efficiency we will continue to have PV that has useless $/W. It is far more important to ignore efficiency and focus on $/W.

I won't use PV if it costs me $20,000 to fit a PV array. If I could fit a $2000 PV array we'd be talking. So what if that takes up 50 square metres of roof space instead of 5? Cheap stuff could even be made into roofing tiles. It is reducing the $/W that makes PV practical.

It is a real shame that Boeing will spend huge dollars to inflate their egos with high efficiency while more practical programs like http://masseynews.massey.ac.nz/2007/Press_Releases /04-04-07.html [massey.ac.nz] struggle.

Re:Efficiency is not really important (1)

mdsolar (1045926) | more than 7 years ago | (#18714625)

The choice on cost (so far) looks to be between 50 square meters and maybe 100 square meters. Nanosolar [nanosolar.com] will likely come in cheaper (per unit power installed) than standard silicon but it may not have the efficiency so you either need more roof or you need yard space that you don't want to use in another way. Because it takes work to install, the materials would likely have to be nearly free to make your $2000 price point, unless you want to do the installation yourself.

On the other hand, if you are not borrowing, you can usually match what you pay your utility in most parts of the country using silicon over the life of the system and the system will likely fit on your roof. It is a close calculation and in some cases utility rates are high enough that even borrowing can break even or save you a little. Usually you can't beat what you'd end up with if you invested the money elsewhere, say on efficiency. If the up front cost is a problem you can rent a solar power system instead. In this case, you match your utility and fix your rate for up to 25 years. This can lead to savings over time if utility rates go up. This also leaves your equity available for other uses.

You can explore this option at http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html [blogspot.com]

Bullwhoey (3, Insightful)

SuperBanana (662181) | more than 7 years ago | (#18714417)

The power convesion ratio is not really that important in itself. The only really important measure is $/watt.

Right, and the only thing that matters with hard drives is $/GB ratio? People don't size systems based purely on $ figures; required output weighs into the equation heavily, since systems usually pay themselves back pretty fast. It doesn't matter when you have a whole hillside or roof, but otherwise, size is important, and the more efficient a panel, (duh), the smaller. That matters for space availability and wind loads.

For example, it's not practical to put solar panels on the roof of a UPS truck; you could cover the entire roof, and even on a sunny day, you probably still wouldn't be able to supply enough energy to keep it going on a day's worth of deliveries. Increasing the efficiency matters here. Likewise for say, putting a solar panel on the back of a cell phone.

The other arena this helps in? Wind loads. If you have a residential system with several panels on a tracking frame, if the panels can be half the size, that means a cheaper frame and tracking system, and less of an eyesore in your back yard. Or, alternatively, twice as much power from the same frame.

What really matters is retail availability. I've been reading about advances in solar panel technology for years, and it's dripping into the consumer market like molasses. Why? Well, for one thing, oil companies are snapping up solar intellectual property and companies like crazy...

Re:Efficiency is not really important (1)

umbrellasd (876984) | more than 7 years ago | (#18714471)

This isn't the whole story. Efficiency is very important because it determines what amount of surface area you need for a particular amount of power. It does us very little good to invent a virtually cost free type of solar power if the surface area (land) requirements are enormous (in which case it is far from free because no matter how cheap the material, maintenance will be a bitch).

If the cheapest alternative is to cover a geographically significant area of land with collectors, the alteration in albedo would have a noticeable impact on weather, as well as flora and fauna in the region. It's true that it is a mistake to focus only on efficiency, but only to a point. Also, as I alluded to above efficiency is directly related to the materials cost component of $/watt.

The scientists in solar energy (most that I know) are concerned with efficiency for good reason. And that reason is economics.

Re:Efficiency is not really important (4, Insightful)

s_p_oneil (795792) | more than 7 years ago | (#18714517)

No, $/Watt is NOT the only important measure for PV cells. Here are some cases where it is not (these examples are extreme to drive the point home):

1) What if I could sell you PV cells that cost 1% the $/Watt of traditional PV cells, but 1 acre of it only generated 100 Watts? Now you need an acre of land to power each 100 Watt light bulb.

2) What if I could sell you PV cells that cost 1% the $/Watt of traditional PV cells without taking up that much space, but they required 10 times as much maintenance after they were installed, perhaps even needing to be replaced every year or 6 months? You going to pay someone to keep reinstalling it?

3) What if I could sell you a bunch of super-cheap reflectors to focus the sunlight onto one tiny but expensive PV cell? If my parents, or possibly even my neighbors, had one of these when I was a pre-teen, I'll bet I would've been up on the roof with a big mirror or lens playing around with my nifty "fire ray", and I would not have been alone in trying that. And what about pine trees? I wouldn't want pine needles bursting into flame as they fall through the concentrator on my roof, so the concentrators would need some sort of enclosure, which limits their size, and thus their power.

I might be able to come up with other scenarios if I give it more thought, but I think you get the point. The PV cell's $/Watt cost is not the only cost to consider.

These guys are sounding like a broken record (0)

Anonymous Coward | more than 7 years ago | (#18713563)

The new panels are able to produce sixty times the current of traditional models.

Yeah, right around the time that AI finally works, fusion power becomes practical, and pot is legalized.

current is a bogus measure (2, Insightful)

khallow (566160) | more than 7 years ago | (#18713567)

Recall that most solar cells on the market acquire 10-20% of the energy that falls on them. Electrically, power is current times voltage. So this is a bogus claim. There's no point to claiming that the solar cell gets "60 times the current" while ignoring voltage (which dropped by an unspecified amount), and ignoring that there's only a theoretical factor of 5 to 10 possible improvement in power over current solar cells.

Monty Python (4, Funny)

Toe, The (545098) | more than 7 years ago | (#18713635)

There was a Monty Python episode where they were comparing penguin brains to human brains. They found that if the penguin were scaled up to human size, its brain was still smaller than a human brain. But -- and this is the important part -- it's larger than it was before!

Re:current is a bogus measure (0)

Anonymous Coward | more than 7 years ago | (#18714529)

Increasing the amount of current generated is significant as once they are able to eliminate as much internal resistance in the solar panel as possible, then the cost per watt will drop (I can't wait until it becomes possible to have the issue of how much wattage per area is acceptable as current designs are just not fiscally feasible yet for small areas). Currently, they are losing an unspecified voltage in the device itself, which is bad because this will increase the temperature of the unit by a much larger margin had the internal resistance been minimized and ultimately decrease the lifetime of the panel unless higher grade material are used, which will then drive the cost per watt up again.

What they have: V = IR
What they want: V = Ir
What we have now: V = ir

Anyway, advances in energy generation are always a positive thing. Electrical circuits are theoretically 50% efficient while gas powered engines are only theoretically 25% efficient. Now, all we need are greater energy density batteries and we will be set to get rid of terribly inefficient, portable, gas engines (Large natural gas engines are fine for the time being as part of the energy lost to heat can be recovered while portable gas engines are on the most part unable to utilize the heat lost). (I am currently pursuing an Electrical and Computer Engineering degree.)

60 is misleading (5, Insightful)

Harmonious Botch (921977) | more than 7 years ago | (#18713583)

It's power that matters, not current.
The best solar cells today get about 13 watts / square foot. The toatl power available on a sunny day with near perpendicular light is 130-140 watts. So efficiency is near 10%. The best a new design can do is about 10-11 fold increase, not 60.

Re:60 is misleading (1, Insightful)

pete-classic (75983) | more than 7 years ago | (#18713705)

The whole article is pretty nonsensical.

Traditional solar panels are often flat and bulky. The new design features an array of nano-towers - like microscopic blades of grass - that add surface area and trap more sunlight.


I'm no Scientist, but that whole paragraph reeks to me. What does "flat and bulky" mean? What does "trap" "sunlight" mean? How can the surface area of the panel being greater than the area covered by the panel help? How do "nano-towers", which are presumably structures that extend toward the light, help? (Given that they'd be more or less parallel to the direction of the photon's travel.)

-Peter

Re:60 is misleading (1)

shaitand (626655) | more than 7 years ago | (#18714315)

'What does "flat and bulky" mean?'

Flat and Bulky.

'What does "trap" "sunlight" mean? How can the surface area of the panel being greater than the area covered by the panel help? How do "nano-towers", which are presumably structures that extend toward the light, help? (Given that they'd be more or less parallel to the direction of the photon's travel.)'

Photons strike existing panels. Some are absorbed in the right places and convert to electricity (about 20% of them), some are absorbed and convert to heat, most bounce off the panels. These new panels have solar cell nano-towers for these photons to hit and convert to electricity. If they bounce again they might hit another tower or the base surface again.

The ultimate benefit is that you can use a panel with depth to collect more photons in a less sprawling panel.

Re:60 is misleading (1)

MadAhab (40080) | more than 7 years ago | (#18714407)

I don't know if this particular technology is related, but there was a "new improved" solar panel material talked about a couple years ago. It used some kind of laser etching to make nano-forests of carbon pine trees. The shape and the density turned out to be really good at trapping light, allowing them to make "blacker" solar panels that captured more light. Who knows, maybe it turned out not to be durable in tests, giving it too short a lifespan to justify the cost. Maybe it just turned out to be bad data.

As usual, there are lots of promising technologies that never turn out to be practical. Some of them turn out to be useful enough to use in certain situations, but nothing that would change the world.

Re:60 is misleading (2, Insightful)

anagama (611277) | more than 7 years ago | (#18713865)

Actually, it sounds like what is happening is that nano-towers increase surface area. The FA is short on details but perhaps they are increasing the surface area sixty-fold by making it very very crinkly. In other words, a tile that is 1 sq ft may have an effective surface of 60 sq ft. In this way, they could get 60 times the juice from a tile with the same outside dimensions as a flat solar cell. Even so, the crinkly cell might still be only 10% efficient -- the extra electricity is simply a factor of the increased surface area. Of course I'm ignoring the voltage loss here -- I'm just saying that there may well be a difference between a 60x increase in power and a 60x increase in efficiency.

Re:60 is misleading (4, Insightful)

anagama (611277) | more than 7 years ago | (#18713903)

On second thought -- I think GP is right and my post is wrong. If a regular cell can extract 10% of the energy out of a 1 sq ft area, even an uber-crinkly cell couldn't get more than 100% of the energy that falls in that space, so a ten fold increase does seem to be the max. Perhaps we need a "think more" button next to the "preview" button.

Re:60 is misleading (1)

The_Wilschon (782534) | more than 7 years ago | (#18714263)

Perhaps we need a "think more" button next to the "preview" button.
I think that's the best idea I've heard all minute!

Solar is about 1 KW/Meter^2 (no concentration) (1)

HornWumpus (783565) | more than 7 years ago | (#18713971)

It doesn't make any difference how rough the surface is. Will a rough surface make the daily average shadow of the panel any bigger? If not there is no more energy to collect.

TFA doesn't claim increase in power, just current. Anybody who paid attention in middle school science knows Power=Voltage*Current.

Re:60 is misleading (1, Interesting)

Anonymous Coward | more than 7 years ago | (#18714117)

Actually, even in the Airzona desert, which receives on average 250 watts/m^2 daily, more than most places on Earth, the watts per square foot is only about 19. If the best panels on the market produced 13 watts per square foot, that would be quite outstanding.

Your maths are wrong somewhere.

Re:60 is misleading (0)

Anonymous Coward | more than 7 years ago | (#18714721)

Direct sunlight at 1 AU has ~1400 W / m2 (minus atmospheric absorbence), your 250 figure is a DAILY average which includes nighttime and obliqueness.

Is solar really green? (2, Insightful)

rsilvergun (571051) | more than 7 years ago | (#18713587)

I've heard that the energy cost of making the panels is greater than the amount of power they generate in their lifetime. Don't know if that's true though, but it takes energy to make the panels, and they do wear out / break.

Re:Is solar really green? (1)

bahwi (43111) | more than 7 years ago | (#18713609)

Yes, but so do coal and oil plants, as well a nuclear. But no, they aren't quite green yet, but let technology improve and demand improve and let them get there. (If we never improved powers such as coal and oil they would not be considered a valuable source now)

Outdated canard (4, Informative)

StefanJ (88986) | more than 7 years ago | (#18713735)

I'm tempted to say "Cripes, This Again," because it comes up in almost every discussion about solar cells.

Instead I'll say: That may have been true once, but it isn't any more. It will become less and less true with time, as learning economies and economies of scale come into effect.

Re:Outdated canard (-1, Flamebait)

timmarhy (659436) | more than 7 years ago | (#18713843)

production of the cells is far more toxic then if you just burnt the equivilant amount of coal. if they can come up with a way to over come this - great - if not, lets move on shall we hippies?

Re:Outdated canard (4, Interesting)

MyNymWasTaken (879908) | more than 7 years ago | (#18713945)

Do you have any references to back up that claim with?

The fact that you closed with an ad hominem barb leaves me doubtful. More referenced research and less willfully ignorant babble please.

Energy pay-back time and CO2 emissions of PV systems [wiley.com]
"energy pay-back time was found to be 25-3 years for present-day roof-top installations and 3-4 years for multi-megawatt, ground-mounted systems. [...] This leads to the conclusion that in the longer term grid-connected PV systems can contribute significantly to the mitigation of CO2 emissions."

(found by typing 'photovoltaic payback time' into google)

Re:Outdated canard (2, Funny)

drix (4602) | more than 7 years ago | (#18714063)

Also, it's really difficult to trust someone who cannot spell the word equivalent. It seems like that word would come up a lot in the field of, you know, science.

Re:Is solar really green? (0)

Anonymous Coward | more than 7 years ago | (#18713753)

http://www.solarshop.com.au/solar%20panels%20page. htm [solarshop.com.au]

The energy payback time is less than 2 years

Re:Is solar really green? (4, Informative)

evanbd (210358) | more than 7 years ago | (#18713833)

Electric power delivered to me at home is about $0.10/kwHr. Solar panels are about $5/w for the panel or a bit less. Grid tie inverters are a bit under $1/w (at least in the low kilowatts range). It's a bit pricier if you want batteries and completely off-grid, but I'll assume a simple grid tie system designed to reduce your utility bill.

That means your solar panel needs to produce 60,000 wHr of electricity per watt to pay for itself, ie it needs to operate for 60k sunny hours. That's about 25 years or so, in a reasonably sunny mid-latitude climate. That's about the life of the solar panel.

Now, that only sort of answers how green they are. In terms of carbon budget, they probably come out ahead -- not all the cost of the solar panel pays for the energy to make it, there are other costs as well. In terms of total pollution, I don't really know -- there are some nasty chemicals involved, but I think the silicon industry in general is pretty good about disposal (I don't know details off hand, sorry). I don't think there are any subsidies on the manufacturing, just tax credits and such when you buy them, so I think I've fully accounted the costs.

So, overall, I'd guess they're marginally greener than the alternatives. Solar panel prices are falling rapidly, which means they're getting greener to make (at least if we assume manufacturing techniques aren't getting messier). I'd guess they start to come out clearly ahead in the next couple years.

Re:Is solar really green? (0)

Anonymous Coward | more than 7 years ago | (#18713987)

On the other hand, you and I are both going to be dead in 40 or 50 years - so who gives a shit?

Re:Is solar really green? (3, Interesting)

Animats (122034) | more than 7 years ago | (#18714135)

When Mark Pinto of Applied Materials spoke at Stanford in EE380 two weeks ago, he said that the current energy payback time on their solar panels is two years, and they're trying to get that down to six months. Some of the fab steps borrowed from semiconductor processing, where the areas aren't so large, can be improved.

Myth. Solar has a VERY good energy payback (5, Informative)

taharvey (625577) | more than 7 years ago | (#18714455)

This is one of those grand myths that the public just can't shake. Photovoltaic's have a very good energy return on investment (EROI).

The energy payback peroid for various PV cell types are:
Crystal Silicon: 3.3 years [chem.uu.nl]
Multicrystal Si: 0.8 years [chem.uu.nl]
CIS: 0.4 years [chem.uu.nl]

To put that is perspective of EROI:
Photovoltaics (Si): 60:1 - 10:1 (based on above)
Wind: 60:1 [awea.org]
Coal(US average): 9:1 [eroei.com]
Nuclear (light water): 4:1 [eroei.com]
Oil (mid-east): 10:1 - 30:1 [eroei.com]
Oil (US): 3:1 or less [holon.se]

And that is keeping in mind that the lifespan of PV is calculated at 30 years, an arbitrary number picked to equalize it with the life of a coal or nuclear power plant, however are panel warranties are 20-30 years alone. There is no reason to believe that the average lifespan of a PV panel won't be 40-60 years or more.

Is this supposed to be a bad joke? (4, Funny)

rolfwind (528248) | more than 7 years ago | (#18713591)

Sunlight has never really caught fire as a power source


Besides the bad pun... you obviously have never used magnifying glasses on poor helpless insects...

Speaking of sunlight as a power source (1)

Beryllium Sphere(tm) (193358) | more than 7 years ago | (#18714445)

Here's a favorite brainteaser of mine. How many commercial power sources can you think of that aren't ultimately derived from sunlight? I've come up with three.

Re:Speaking of sunlight as a power source (1)

dave1g (680091) | more than 7 years ago | (#18714565)

nuke(fission), geothermal(gravity/fission), tidal(moon gravity). I can't use regular hydro cus it took sunlight to evaporate the water so it would rain over land.

Re:Speaking of sunlight as a power source (2, Funny)

turing_m (1030530) | more than 7 years ago | (#18714819)

You forgot Chuck Norris.

When you think about it... (0, Flamebait)

Eric Damron (553630) | more than 7 years ago | (#18713677)

the best solution to our energy problem in the long run would be some source that doesn't deplete anything on our planet. That pretty much leaves solar, wind, geothermal and tidal. And it could probably be argued that geothermal would cool the earth's core faster.

What I absolutely do not want, however, is the same greedy bastards that are raping us now for our energy to control the development of future energy. Think about it. If they have a choice of giving us near free energy or continuing to corn-hole us, which do you think they'll choose?

Re:When you think about it... (1)

biocute (936687) | more than 7 years ago | (#18713765)

If they have a choice of giving us near free energy or continuing to corn-hole us, which do you think they'll choose?

To give us near free energy?

Seriously if a company can get hold of an exclusive technology to produce unlimited energy, it will offer to the public at near free cost, and perhaps charge "fees" for installation, support and services.

Re:When you think about it... (2, Insightful)

Mr. Roadkill (731328) | more than 7 years ago | (#18714015)

Seriously if a company can get hold of an exclusive technology to produce unlimited energy, it will offer to the public at near free cost, and perhaps charge "fees" for installation, support and services.
No, I think you've probably got that wrong.


They'd offer it to the power distribution and oil companies - probably on terms that guarantee a revenue stream well past the expiration of any patents on the technology. Why handle the messy details of dealing with the Great Unwashed one-on-one, when others who could be your customers already have the billing systems and the customer bases in place? And with unlimited clean near-free electicity to play with, the oil companies would find ways to produce hydrocarbons from sea water and atmospheric carbon dioxide pretty damn fast - they've got the storage and distribution expertise, and from a storage and usage perspective you have to admit that fossil hyrdocarbons are pretty damn convenient (if not particularly good for the environment). Synthetic hydrocarbon fuels would be carbon-neutral - the waste products are the same as the raw materials, water and carbon dioxide.


Re:When you think about it... (1)

mdsolar (1045926) | more than 7 years ago | (#18714817)

They are actually going to use the concentrated CO2 from flu gas http://www.greenfuelonline.com/ [greenfuelonline.com] . The free energy source is, as (almost) always, the Sun: http://mdsolar.blogspot.com/2007/02/photosynthesis .html [blogspot.com] .
--
Sprout Silicon Leaves:http://mdsolar.blogspot.com/2007/01/slashdo t-users-selling-solar.html [blogspot.com]

There's NO free lunch (1)

Toe, The (545098) | more than 7 years ago | (#18713783)

If we had so many wind turbines that we were collecting enough power to run the world, would that not have some effect on the global wind patterns?

Also solar power cools the Earth's surface. Solar farms are envisioned as acres and acres of panels in the desert. That would turn a very hot spot into a very cold spot, changing the currents there, and thus affecting overall temperature distribution (ie, the wind).

Same sort of thing goes for tidal energy. If you collect enough, you are going to affect life in the ocean. There just ain't no free ride.

But there are two viable solutions:

  1. Solar panels in space, not in orbit around the Earth. But this has the little problem of getting the power to the Earth. Even if we can beam it... that is just asking for trouble.
  2. Radical Idea: Use less energy. But who's gonna make money off that? Yuck!

Re:There's NO free lunch (5, Insightful)

Planesdragon (210349) | more than 7 years ago | (#18713951)

If we had so many wind turbines that we were collecting enough power to run the world, would that not have some effect on the global wind patterns?

No. There is simply more power in the Earth's wind than we could harvest. Or, if you please, the current annual input of power into the atmosphere is greater than the total energy cost of human civilization, by a few orders of magnitude.

Remember: every single watt of solar power that reaches the ground winds up in the atmosphere as heat, the foundation of wind.

Also solar power cools the Earth's surface. Solar farms are envisioned as acres and acres of panels in the desert. That would turn a very hot spot into a very cold spot, changing the currents there, and thus affecting overall temperature distribution (ie, the wind).

If, and ONLY if, the solar panels were not only almost perfectly efficient, but also sucked energy from heat in the atmosphere.

Same sort of thing goes for tidal energy. If you collect enough, you are going to affect life in the ocean.

Tides are powered by the moon's gravity, bub. Sure you'll have an effect, but the tides are already affecting the moon's rotation.

There just ain't no free ride.

Depends on what you means as "free." Sure, the soup kitchen needs someone to pay for the soup, but the bums getting a hot meal get to enjoy someone else's largesse. Most of the power sources available to humanity work like that, including photovoltalic solar, fission, and hydroelectric.

Re:There's NO free lunch (1)

Toe, The (545098) | more than 7 years ago | (#18714071)

In all of your scenarios, you're not incorporating the impact of harvesting the power. What would it take, physically, to harvest the world's demand of power using tidal forces, even assuming extreme efficiency? Don't you think those collectors would have some effect on the inhabitants of the ocean?

Re:Upper limit (2, Interesting)

Migraineman (632203) | more than 7 years ago | (#18714561)

Recently, I was having a conversation about the upper limit on solar power. I hadn't done the math then, but I just trotted out a fresh napkin to satisfy my curiosity. The earth is 12756 km in diameter. That presents a 127.8 million km^2 cross section to the sun. With the napkin-math estimate of 1kW/m^2 incident at the earth's surface, there's an upper limit of 127.8 million MW of power available from the sun. Okay, so that's an absolute ceiling for terrestrial solar collection - you can't collect more energy than is incident in the first place.

Okay, now for a more practical limit. Let's put the solar collection grid on land - that's a reduction to 30%. [physicalgeography.net] Let's also go with solar cells that are 20% efficient - that's not too shabby, but not bleeding-edge-expensive either. (127.8 * 0.3 * 0.2) = 7.67 million MW.

Finally, how much of the available global land mass are we willing to pave over with solar cells? If I use a residential rooftop model, a 1500 sq.ft. house on a 1/4 acre (~10000 sq.ft., sorry for the non-metric-unit shift) property would be about 15%. I think that's probably a bit high, considering that houses aren't aligned for optimal solar collection, but I'm looking for the practical upper limit of solar collection opportunity. Using 15%, the available harvestable power limit becomes 1.15 million MW.

Let's compare that to current consumption stats in the US [doe.gov] (no pun intended.) If I read this chart correctly, December of 2006 had 335.6 million MWh of power generated across all industries. There were 744 hours in December, so that equates to 451 thousand MW average continuous power generation. So the maximum solar harvest potential is only about 3x our current consumption rate? Damn, that's sobering.

Re:Upper limit (0)

Anonymous Coward | more than 7 years ago | (#18714707)

"The earth is 12756 km in diameter. That presents a 127.8 million km^2 cross section to the sun. With the napkin-math estimate of 1kW/m^2 incident at the earth's surface, there's an upper limit of 127.8 million MW of power available from the sun."

I think you mean 127.8 billion MW there, which turns your worrying factor of 3 into a comforting factor of 3,000.

Re:There's NO free lunch (1)

pushing-robot (1037830) | more than 7 years ago | (#18713955)

Solar panels in space, not in orbit around the Earth. But this has the little problem of getting the power to the Earth.
That's easy. Just run cables down alongside the new Internet tubes.

Re:There's NO free lunch (2, Funny)

MrLeap (1014911) | more than 7 years ago | (#18713989)

You're right about the fact that beaming power from space is bad news. Simulations in sim city show that microwave energy has a 5% chance to destroy Las Vegas... monthly.

Re:There's NO free lunch (2, Insightful)

Anonymous Coward | more than 7 years ago | (#18714131)

Large buildings and cities have much more of an effect on local wind patterns than wind farms do. "Global wind patterns" on the other hand occur in the atmosphere above any of this. You know, the atmosphere that extends up a few dozen miles, or many thousands of times higher than a wind turbine? Your claim is like saying a thin film of bacteria at the bottom of a river will affect the water current. Global warming, on the other hand, affects a large portion of the atmosphere and will likely cause changes in the wind patterns.

Solar panels don't cool the Earth's surface. Actually, it's the opposite as their albedo is lower than that of desert sand so more of the sun's energy is trapped instead of being reflected back into space. However, even if the entire southwestern US was covered with solar panels this effect on Earth's total albedo would be far less than the effect from the loss of the Northern polar ice cap (white ice suface being replaced by dark water). Beaming solar energy from space would probably be slightly worse than covering the deserts with solar panels, as this adds energy to the system that would otherwise not hit the Earth (most electricity is converted to heat when used).

Collecting tidal energy only affects the immediate surroundings of the facility. Certainly you should make sure to build this stuff where it doesn't cause harm. But it cannot change the effects of the tides anywhere else, as the tides are driven by gravity and Earth's rotation. These are things that can not be significantly affected by anything we do, unlike the atmosphere which we are affecting by continuing to emit huge quantities of CO2.

You should quit believing in the moronic strawmen concocted by people who oppose environmentally friendly technology. All of these are perfectly viable and a LOT better than coal.

Re:There's NO free lunch (1)

Falladir (1026636) | more than 7 years ago | (#18714393)

Even if we can beam it... that is just asking for trouble.

You played SimCity 2000 too? I have to say that game put me off Microwave power for good.

Silly arguments (1)

taharvey (625577) | more than 7 years ago | (#18714615)

Those examples are absurd. First we already have a fusion energy source that beams energy from space that can be captured by receivers anywhere on earth - it is called the *sun*. And the receivers? You guess it - solar panels.

The sun just happens to put out wireless directed energy over the whole surface of the earth, energy dense enough to be very useful, yet not too dense as to be dangerous.

No mega clusters of PV are needed. There is 262 billion square ft of rooftop space in the US (according to census data), 246% more surface area than we need to produce all of the US electrical demand with 17% efficiency Panels. That doesn't even count parking lot surface area, or other multipurpose structures.

Light that would turn to heat on your roof, ends up displaced as heat 20 feet away in your refrigerator. No environmental concern here folks, move along.

Even produced at a distance, the net heat balance on the earth is the same. Not so much could be said for fossils or nuclear.

Re:There's NO free lunch (1)

tolomea (1026104) | more than 7 years ago | (#18714827)

The other poster did a nice job of shooting down you post but he missed one. If we collect solar energy in space and beam it to earth then there will be more energy entering the earths atmosphere. After we are done using that energy it has to go somewhere, the most likely thing is that it will get emitted as heat by all the devices we run off that power, and if we don't arrange for that heat to vent out into space somehow then things will start to warm up.

I've heard it all before... (0)

Anonymous Coward | more than 7 years ago | (#18713711)

In an ideal conversion you can get about 1KW per square meter when the sun is directly overhead.

Call me when you get something that is more than 0.5KW/m^2 and that doesn't rival titanium on the "nasty to manufacture" scale.

Until then it's all just blah blah blah trying to make your University look good in the press.

In-depth article from the real source. (2, Informative)

Anonymous Coward | more than 7 years ago | (#18713763)

The op article was vague and didn't have the pretty picture the one below has:

http://gtresearchnews.gatech.edu/newsrelease/3d-so lar.htm [gatech.edu]

What Don Imus said was FUNNY! (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18713841)

Jiggaboooooos BAhahaha Nappy headed chickenheaded HOS

Re:What Don Imus said was FUNNY! (1)

iminplaya (723125) | more than 7 years ago | (#18714089)

Sup, homes [slashdot.org] ?

New technology? (1)

eclectro (227083) | more than 7 years ago | (#18713879)

Solar panels that opens? Do they use pulleys or motors? Isn't this kind of obvious? Prior art anyone?

I wonder if it is anything like... (1)

MrCreosote (34188) | more than 7 years ago | (#18713943)

this [anu.edu.au]

Cost comparisons (5, Interesting)

aegl (1041528) | more than 7 years ago | (#18713959)

People keep dismissing solar because it can't compete in price against traditional large scale ways of generating electricity.

But it doesn't matter to me that some hydro-electric plant far from my house is making power at $0.02 per kWh, what matters to my economic reality is that my local power company charges just over $0.08 for the first dozen kWh delivered each day and then has a sliding scale that goes up to $0.36 kWh for increased amounts of power.

Before I installed solar panels a high percentage of my power was costing me that top rate. So the relevent economic calculation for me is the cost to install my panels divided by the expected number of kWh that they will generate across their lifetime. This number comes out at about $0.16 per kWh. So I'm better than breaking even now, and assuming that energy prices continue to rise, I'll do even better in years to come.

The final kicker in the equation is that I've switched to a time-of-use tariff so across the summer the power company will credit me with $0.209 for excess power that I generate in peak hours (between 1pm and 7pm), and $0.112 for partial-peak (10am-1pm + 7pm-9pm).

If I'd taken the capital that I used to install the panels and invested it instead, I'd have to maintain a >19% annual pre-tax rate of return to beat the panels. Possible, but extremely unlikely (especially with my stock-picking track record!).

Re:Cost comparisons (1)

_Sharp'r_ (649297) | more than 7 years ago | (#18714805)

Hard Money lending. Generally a minimum $50K investment, but returns a minimum 24%, in my experience averages closer to 30% once they go late and start paying 2%/month late fees on top of the interest. (Most people underestimate how long its going to take them to get their conventional commercial financing.)

Since a title company handles it all and insures the title, you get a first position mortgage (trust deed) recorded and shouldn't loan on anything higher than a 75% loan-to-value ratio, its also much less risky than most stock market investments.

Tag (4, Funny)

Archangel Michael (180766) | more than 7 years ago | (#18713973)

Why isn't this tagged "itsatrap"???

Re:Tag (1)

Null Perception (914562) | more than 7 years ago | (#18714317)

Wait! Don't tag it 'itsatrap', itsatrap!

TOO FUNNY!!! That's impossible (1, Informative)

Anonymous Coward | more than 7 years ago | (#18714025)

Ok, I'm a solar cell expert. I've been buying and selling solar cells/panels for years and I also construct panels with 0.5V 2 to 6A single-crystal cells... Now, take it from me, it is IMPOSSIBLE to construct a solar cell that is 60 times more efficient... like these other people are saying, the voltage would have to be considerablly less for the current to be 60X higher... the reason being is that THERE ISN'T EVEN THAT MUCH LIGHT COMING FROM THE SUN!!!!!! There are already cells out there that surpass 35% to 40% efficiency so DOUBLE would be an enormous step, but even 4X the efficieny is impossible.

Sorry guys.

Re:TOO FUNNY!!! That's impossible (0)

Anonymous Coward | more than 7 years ago | (#18714699)

Perhaps it has a new sunlight sucking material with 60x the suction.

Re:TOO FUNNY!!! That's impossible (1)

antisoshal (639054) | more than 7 years ago | (#18714741)

if you are an expert, you might wanna work on reading skills. No where does it say 60 times more efficiant. It says 60x the current, and an unspecified but dramatic drop in voltage. I.E.. they dont actually claim an increace in effeciency at all as best as I read. Hope your expert service includes much better information processing that youve demonstrated, or its no wonder solar power doesnt catch on with experts of this caliber.

Great (4, Funny)

TheRealMindChild (743925) | more than 7 years ago | (#18714057)

Now all we need is something that can trap more girls and well be set!

What a useless article.... (4, Informative)

dyslexicbunny (940925) | more than 7 years ago | (#18714061)

It's like a third grader's book report... Why don't we just get the water from the well... from GTRI's site [gatech.edu]

Just out of curiosity... (2, Interesting)

Reality Master 101 (179095) | more than 7 years ago | (#18714085)

Maybe a power engineer can answer this... the obvious way to build a solar power plant is to take a whole slew of lenses and focus them on a water tank, and then turn a turbine. Given that heat -> power is a fairly mature technology, wouldn't that be more efficient than solar cells?

They've built at least one test sight. (2, Informative)

HornWumpus (783565) | more than 7 years ago | (#18714159)

The tracking motors etc for the mirrors are the deal breaker.

The only number that matters is $/watt. If they're cheap but inefficient we just cover the whole roof. If we run out of roof there is plenty of space in the western US.

Re:Just out of curiosity... (1)

dhasenan (758719) | more than 7 years ago | (#18714229)

The photoelectric effect is more direct, so it likely has less energy loss. Specifically, the hot water tank has a lot of surface area exposed to cool air that sucks energy from it. So, no, that's a pretty lousy way to make electricity.

Re:Just out of curiosity... (2, Informative)

smegged (1067080) | more than 7 years ago | (#18714425)

Actually there is a far better technology out there which does what you talk about.

Lloyd Energy [lloydenergy.com] have developed a solar system which stores thermal power in the form of heat in huge blocks of graphite. You can then get that heat out and convert it to energy. This has two uses - taking power at off peak rates and storing it, selling it back to the market when the spot price of electricity is high, and the other is to focus a series of mirrors on the graphite so that it heats up, storing the energy for use whenever you wish.

The issue with this system is that it's slightly more expensive, but it can be used profitably by selling back to the grid at peak times (when power sometimes costs up to $10 000/MWh in Australia).

Re:Just out of curiosity... (1)

ookabooka (731013) | more than 7 years ago | (#18714521)

Given that heat -> power is a fairly mature technology, wouldn't that be more efficient than solar cells?

What about Molten Salt [fsu.edu]

A Better $TRILLION (1, Insightful)

Doc Ruby (173196) | more than 7 years ago | (#18714231)

Man, I wish we'd spent that Iraq War $TRILLION on solar research instead.

If we just got all its 212 possible oil barrels, that would have been $4.72 a barrel (enough to get 50M Americans to vote for it), but we probably won't get any of it now - unless we buy it from Iran.

That 750Pj could come from the Sun (at 1KW:m^2) into 4000K square miles (0.1% of the US total area) in 2.5 years. At 25% efficiency, that would be 10 years. We're already halfway through that alternate decade, we've only wasted huge amounts of energy (and life and limb), and are giving Iran the oil (to sell to us at $100 a barrel).

Investing $250M per square mile in American solar production would have actually secured America, especially from the oil terrorists, at home and abroad.

Dumb question (4, Interesting)

lawpoop (604919) | more than 7 years ago | (#18714235)

Hey, if you have solar panels on your roof, how often to you have to wash them? Do they develop a film that reduces their efficiency?

what we need is (1)

kaizokuace (1082079) | more than 7 years ago | (#18714483)

open source power supply... mehahahaha yes, GNUTowers.

Mirrors (1)

a1mint (1021941) | more than 7 years ago | (#18714515)

How about using cheap mirrors to bounce off some extra light unto those expensive solar panels, and increase the output that way. Oh wait ! The solar power companies doesn't want you to know that . . . Or else the corrupt patent system actually issued a patent on that . . . nuts . . .

That's not news (4, Informative)

mkwalker (471266) | more than 7 years ago | (#18714567)

Where's the news in a half finished project that doesn't deliver any benefits (so far) on existing technologies? Who was the fool that got suckered into producing an infomercial?

This is news: http://www.abc.net.au/catalyst/stories/s1865651.ht m [abc.net.au]

Sliver cell solar technology. This was on Australian TV in March. Generating the same amount of power using a fraction of the silicon required today. Brilliant.

Re:That's not news (1)

bunbuntheminilop (935594) | more than 7 years ago | (#18714765)

I listen to the ABC radio podcast called 'the science show'. Going by that, science reporting in Australia is fantastic. I'm in New Zealand, and I hear more interesting stories on the science show about New Zealand scientists than I do in the regular media.

Re:That's not news (1)

mkwalker (471266) | more than 7 years ago | (#18714821)

The Science Show has been going since 1975. It's a fantastic source of all things science from around the globe. If it was a TV show it would have been canned long ago. Long live radio!

Traps More Light.....? (1, Funny)

IHC Navistar (967161) | more than 7 years ago | (#18714749)

The Department Of Homeland Security has installed new solar panels throughout the United Stares. When asked about the new panels, DHS stated that it is part of the new Early Warning System. However, anonymous DHS insiders have leaked in formation that reveals far more deatils about the panels than is being officially disclosed.

"The new panels are designed to trap more light, so that we can trap it, and neutralize its threat to the American public. After the rougue photons are trapped, they are then sent to Guantanamo Bay, where they undego interrogations as to why they are violating sovereign American airspace, and why they are trying to enter the United States without the proper documentation." said a DHS source on condition of anonymity.
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