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Quantum Dots Could Double Solar Energy Efficiency

kdawson posted more than 4 years ago | from the hot-enough-for-ya dept.

Earth 112

dptalia notes the recent publication in Science of research demonstrating a way to use hot electrons in solar cells, resulting in an overall energy conversion efficiency of 66%. Here is the abstract in Science; access to the full article requires a subscription. "A team of University of Minnesota-led researchers has cleared a major hurdle in the drive to build solar cells with potential efficiencies up to twice as high as current levels, which rarely exceed 30 percent. ... Tisdale and his colleagues demonstrated that quantum dots — made not of silicon but of another semiconductor called lead selenide — could indeed be made to surrender their 'hot' electrons before they cooled. The electrons were pulled away by titanium dioxide, another common inexpensive and abundant semiconductor material that behaves like a wire."

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Still waiting for breakthrough to be on sale (0)

Anonymous Coward | more than 4 years ago | (#32612256)

These [blink]dots[/blink] are all nice and well, bu how long until the consumer market sees all the improvements?

Re:Still waiting for breakthrough to be on sale (4, Funny)

fyngyrz (762201) | more than 4 years ago | (#32612890)

Same as fusion: Ten years from now, for all possible values of "now."

Re:Still waiting for breakthrough to be on sale (1)

OeLeWaPpErKe (412765) | more than 4 years ago | (#32613988)

This research just a lot of buzzwords in one sentence. Cute : we can make high efficiency devices that take millions of dollars to make : great (except when millions, or even billions still aren't enough to make this "efficient" device : google "ITER"). If you want to make engineering efficient solar panels easier and cheaper, create a cheap low-electrical-resistence transparent material. The ones we have are just plain horrid.

Re:Still waiting for breakthrough to be on sale (0)

Anonymous Coward | more than 4 years ago | (#32615136)

Even "high efficiency" reeks of buzzwordom. A high efficiency organic PV cell clocks in well under 20% efficient, but other commercial cells may be considered high efficiency at 80%.

An ideal occasion to post (0, Funny)

Anonymous Coward | more than 4 years ago | (#32612300)

this: http://raincoaster.files.wordpress.com/2007/07/lil-werner.jpg

Re:An ideal occasion to post (0, Insightful)

Anonymous Coward | more than 4 years ago | (#32612406)

I'd say this was on-topic. Maybe deserving of a Funny mod...

Re:An ideal occasion to post (1)

biryokumaru (822262) | more than 4 years ago | (#32613078)

Slashdot mods realize this joke simply reinforces common misconceptions about the ratification of quantum mechanics with classical mechanics.

Re:An ideal occasion to post (0)

Anonymous Coward | more than 4 years ago | (#32616562)

And those who work to reinforce inaccurate stereotypes about the ratification of quantum mechanics with classical mechanics must be fought at every turn.

How much energy are we talking about? (1)

Murdoch5 (1563847) | more than 4 years ago | (#32612328)

Okay so we can make more efficient solar cells, the question that I want to know is what kind of over all energy increase will this provide?

Re:How much energy are we talking about? (2, Informative)

Anonymous Coward | more than 4 years ago | (#32612408)

RTFA, about 66%

Re:How much energy are we talking about? (4, Insightful)

CarpetShark (865376) | more than 4 years ago | (#32612512)

You're confusing energy conversion efficiency with energy production. The main connection there is that less efficiency means more raw resources for the same result. They're certainly not the same thing.

I think what the GP was getting at is something like, "This sounds way better than past solar conversion efficiency. Can we know build viable solar power stations? What about orbital solar power satellites? Where does this leave coal and nuclear power stations? What will the overall energy production strategy be, once this comes to market, given projected energy needs WHEN it will come to market?"

That's not a set of questions you want to answer too hastily.

Re:How much energy are we talking about? (4, Informative)

elashish14 (1302231) | more than 4 years ago | (#32613254)

I'm no expert, but probably a lot more. Some facilitating factors:

1. PbSe is pretty easy to synthesize as nanorods. TiO2 is even easier. Lower production cost.

2. Higher efficiency (theoretically) than the 40% record achieved using triple junction cells (which have extreme costs and are likely never going to be practical) and the ~25% achievable using single-junction silicon cells (maximum theoretically about 31%).

This should lead to a great increase in the achievable power. The only thing that I'm unsure of is whether you can concentrate the light in nano-confined cells as much as you can in bulk material cells. The (I believe) issue becomes current density saturation either within the material or at the connector interface. Not altogether familiar with the R&D in this area. Since high-efficiency cells can be concentrated efficiently by a factor of ~1000x, this could be a significant effect if nano-confined cells can't be concentrated very much.

Re:How much energy are we talking about? (2, Interesting)

Starcub (527362) | more than 4 years ago | (#32613662)

The only thing that I'm unsure of is whether you can concentrate the light in nano-confined cells as much as you can in bulk material cells.

I would think that quantum dots might be ideal for use in a grid array of something like the dye-sensitized collectors that have recently been developed. I don't think that current saturation would be an issue, as the leads will be distributed evenly at each quantum dot. The problem I see is that increasing the area used for contact wiring will mean increased non-radiative losses. The article states that the wire contacts will be made of semi-conductor material as well, and semi-conductors typically have lower conductivity/higher loss than conductors. Supposedly they are trying to overcome those losses by using a partially generative material as an intermediate between the conducting leads and PbSe cells?

But by when? (3, Insightful)

bhagwad (1426855) | more than 4 years ago | (#32612336)

Seems like I keep hearing of breakthroughs, but nothing ever seems to fucking change!

Re:But by when? (3, Informative)

amorsen (7485) | more than 4 years ago | (#32612584)

Meanwhile, partially as a result of various breakthroughs in solar cell technology, solar cell prices are finally dropping despite unprecedented demand.

Re:But by when? (2, Informative)

ottothecow (600101) | more than 4 years ago | (#32613418)

Large facility demand has actually slowed due to the economy...solar is still a pretty big investment. Prices are dropping and we are seeing some good hard work out of some of the sole-purpose solar companies (First Solar, Sunpower, etc) since they can't fall back on other products like the industrial giants can when solar orders drop.

We are also seeing some cool developments to make solar better. Not just big efficiency gains like this article mentions but also more environmentally friendly processes to make the panels (although replacing silicon with lead "quantum dots" may not be a step in that direction but even the normal production players like sunpower are hitting new efficiency records). As it stands, a lot of petroleum products go into the parts that make the panels...a cool development I saw a press release about a few weeks ago is from somebody called BioSolar [biosolar.com] who have designed a panel backing film based on some bio products rather than oil.

We are also seeing 3rd gen solar tech pick up which will drop costs even if it isn't as efficient (and really, when you are almost at 30% on commercial panels, cost is a bigger issue since we have a LOT of rooftops ready for panels)

Re:But by when? (2, Informative)

Lumpy (12016) | more than 4 years ago | (#32613696)

The ones that are dropping are because of two reasons...

1 - china made junk flooding the market. There is a metric crapload of really low grade Solar panels on the market from china. These low grade panels are also of the worst designs that are easiest to make that flat out suck in real world use.

http://www.amazon.com/Sunforce-50044-60-Watt-Solar-Charging/dp/B000CIADLG/ref=sr_1_1?ie=UTF8&s=hi&qid=1276875660&sr=8-1 [amazon.com]

for example is complete garbage. It's all marketing hype and they fail to tell you that any shadow, even a line from a cable across the panel reduces output drastically.

They do admit to being Amorphous.. I.E. the cheapest to make solar panel. They are about 6% efficient. However, there’s a reason why thin film solar panels haven’t replaced older types yet. They’re just not as efficient. With about a six percent conversion rate for energy drawn from the sun, they can only draw about half the wattage from sunlight that mono and polycrystalline panels do, making them take up twice as much installation space for the same amount of power.

Plus most of these are also built poorly. so the 6% is assuming they were built perfectly. The most I have seen from any of the cheap china panels out there has been around 4%...

I had better luck with really old burned industrial used ones from the solar farms out west. I have a pair of 6 foot panels I bought for $340.00 that are a dark brown from being in the sun for years that put out more power than 4 of the kits' linked above do.

Re:But by when? (1)

SnarfQuest (469614) | more than 4 years ago | (#32614266)

Wow, thanks for the link. Just ordered 2 to power my house.

Re:But by when? (1)

Hatta (162192) | more than 4 years ago | (#32615216)

You can power your house on 120W?

Re:But by when? (1)

operagost (62405) | more than 4 years ago | (#32613802)

It still takes about 5 years to recoup the cost of a residential solar system-- even with huge government subsidies!

Re:But by when? (2, Informative)

falconwolf (725481) | more than 4 years ago | (#32616398)

It still takes about 5 years to recoup the cost of a residential solar system-- even with huge government subsidies!

But energy is free after that whereas you have to keep paying for distributed power, even with huge government subsidies to coal, natural gas, and other fossil fuels. Solar panels are warrantied 20, 25, even 30 years. I think the shortest warranty for hardware are on batteries, yet Surrette/Rolls [wholesalesolar.com] has a 10 year warranty. On the other hand Enersys Batteries [solar-pane...energy.com] only have a 5 year warranty. Even if you have to replace the batteries every 5 years, you still save money.

Some, like you?, complain about subsidies for alternative energy but you say nothing about subsidies for "conventional" energy. Coal? It gets billions of dollars in subsidies, here's, Chevron's CEO agreeing with the Sierra Club to lobby to end coal subsidies [grist.org] . Rep Edward Markey practically brags that My Climate Bill 'Has Huge Subsidies For Clean Coal! Huge!' [youtube.com] . He details some of the subsidies nuclear power and other's get. How about this: Global Dirty Energy Subsidies Top $550 Billion Per Year [politifi.com] . A blog entry on the Financial Times website says The cost of fossil fuel subsidies: $557bn [ft.com] . How about the US? The Policy Archive [policyarchive.org] says that between 2002 and 2008 "Fossil fuels benefited from approximately $72 billion over the seven-year period, while subsidies for renewable fuels totaled only $29 billion."

If you want to complain about subsidies complain about the subsidies conventional energy, and agricultural businesses, get. A Reason blog entry says Agricultural Subsidies: Corporate Welfare for Farmers [reason.com] .

Falcon

Re:But by when? (1)

Brian Feldman (350) | more than 4 years ago | (#32616856)

Do you live in homes for less than five years?

Re:But by when? (0)

Anonymous Coward | more than 4 years ago | (#32615706)

We had quite a cool program to boost solar power here in Germany, no idea, if it made sense ecologically though. ^^
The electricity companies are forced to buy solar power for a certain price that's high above the usual price and the price was guaranteed for 10 or 15 years or something.
So what many people did here was getting solar panels on all their roofs. They sell all the electricity they generate and buy the electricty they need for the usual price and have their investment returned several years, before the time with the guaranteed price is over.

Re:But by when? (0)

Anonymous Coward | more than 4 years ago | (#32615838)

Just to add. When I was taking a look at my neighbors solar equipment like 2 years ago, who has one side of his roof and garage equipped with solar panels, he was generating 15kW on some sunny afternoon.

Re:But by when? (3, Insightful)

Sockatume (732728) | more than 4 years ago | (#32613126)

Things would go a lot faster if more people were saying "how can I make this happen?" and fewer "I was supposed to have a jetpack frownyface exclaimation mark question mark"

Re:But by when? (-1, Troll)

Anonymous Coward | more than 4 years ago | (#32613460)

It would also go a lot faster if those than can make it happen weren't being handed bags of cash by the oil industry.

Re:But by when? (1)

Ex-MislTech (557759) | more than 4 years ago | (#32617628)

I guess someone with oil royalties doesn't like your plan and modded you troll.

Its amazing how the truth has become trolling to those who put
their self interest above the rest of the ppl.

Re:But by when? (1)

MokuMokuRyoushi (1701196) | more than 4 years ago | (#32620012)

Troll? If I were to mod this, I'd have a hard time choosing between "Funny" and "Insightful". A massive amount of solar projects are backed, funded, or controlled by oil companies - most of whom are enjoying their profits in the oil industry. I doubt they want to see the profits slow, even in the slightest.

Re:But by when? (1)

Ex-MislTech (557759) | more than 4 years ago | (#32616734)

If we put 10% of what went into the bailouts into alternative energy
this issue would solved already.

The best minds with a good budget and a effort on par
with the Apollo missions and this would be a done deal.

I think Jetstream wind and Ocean current power need to
be tapped as well as they will take up near zero land.

1% of the World's jet streams would replace all forms of
power on earth.

The strongest ocean current has 125 times the flow
of all rivers on earth combined.

Re:But by when? (1)

blackfrancis75 (911664) | more than 4 years ago | (#32613154)

are you referring to Solar Energy specifically, or in general?

Look outside the U.S. (0)

Anonymous Coward | more than 4 years ago | (#32613476)

In the rest of the world "the breakthroughs" are being embraced and fast-tracked.

Remember, the U.S. is still stuck in a fossil-fuel love affair.

Re:But by when? (0)

Anonymous Coward | more than 4 years ago | (#32614284)

That's because technology, while very useful, is not "The Answer". It's a magical maze. At the beginning of the maze, there are only a few doors to choose from and the locks are fairly easy to pick. However, the deeper we get into the maze, the harder the locks are to pick and the more doors there are to choose from after we get one door open. Every breakthrough leads to 2-3 more difficult problems to solves.

As the saying goes, if you want change, look to the man in the mirror.

what changes? (1)

falconwolf (725481) | more than 4 years ago | (#32615708)

Seems like I keep hearing of breakthroughs, but nothing ever seems to fucking change!

Prices have changed. According to Solarbuzz [solarbuzz.com] per watt costs have dropped from about 5.40 euros or a little over that in US dollars in December 2001 to about 4.20 euros or a little less US dollars for June 2010. Further it says "there are now 488 solar module prices below $4.00 per watt (3.24 euros per watt)". Efficiency has also increased. In 2001 conversion efficiency pushed 12%, in 2009 SunPower [reuters.com] sold panels with conversion efficiencies of 19.3% [thomasnet.com] , the highest [aetsunpower.com] in the industry.

Falcon

Re:But by when? (0)

Anonymous Coward | more than 4 years ago | (#32618240)

Seems like I keep hearing of breakthroughs, but nothing ever seems to fucking change!

Too many pigs in the industry are getting rich and fat of oil to ever let alternatives hit the main stream.

Econuts will be torn over this one (0)

Anonymous Coward | more than 4 years ago | (#32612346)

Will they save the Earth by using these higher efficiency solar panels, or will they hurt the Earth by using lead?

Re:Econuts will be torn over this one (2, Interesting)

Ken_g6 (775014) | more than 4 years ago | (#32612416)

Not a problem; lead's not nearly as bad as the arsenic in some panels!

Re:Econuts will be torn over this one (3, Insightful)

drinkypoo (153816) | more than 4 years ago | (#32612452)

Not a problem; lead's not nearly as bad as the arsenic in some panels!

We need to find a way to get usable arsenic out of contaminated soil. There are literally thousands of tons of it around the world, much of it slated for "cleanup" (secure burial). It's a lot less dangerous when you make it into a solar panel than when it's free to get into groundwater.

Re:Econuts will be torn over this one (5, Interesting)

jlencion (833976) | more than 4 years ago | (#32613402)

Mushrooms such as the matsutake and shaggy mane accumulate arsenic. These could be grown on arsenic contaminated lands and then processed to extract the arsenic: http://books.google.com/books?id=NPI8_-omzvsC&pg=PA103&lpg=PA103&dq=mycelium+running+arsenic&source=bl&ots=38qB71dh2N&sig=jWBgriT6LmoI7ELXTWuy6Vgfm3I&hl=en&ei=uI0bTJOlAZuKNc6gwbcM&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwAA#v=onepage&q&f=false [google.com]

Bring my own lunch (1)

ThatsNotPudding (1045640) | more than 4 years ago | (#32615124)

If I worked there, I would definitely avoid the cafeteria.

Re:Econuts will be torn over this one (1)

PowerEdge (648673) | more than 4 years ago | (#32617428)

Or used to feed to the population of the Pacific Northwest.

Re:Econuts will be torn over this one (0)

Anonymous Coward | more than 4 years ago | (#32619066)

Or used to feed the population of the Pacific Southwest.

Re:Econuts will be torn over this one (1)

Captain Hook (923766) | more than 4 years ago | (#32612478)

Plus, since it's Lead Selenide panels, we could shape and sharpen them into weapons for use against Evolution aliens.

Re:Econuts will be torn over this one (1)

CPerdue (1376115) | more than 4 years ago | (#32612594)

I was wondering the same thing. Do the ROHS rules take into account how a 'bad' substance like lead is bound to other materials? For example, is something in an inert, vitreous blob OK?

Re:Econuts will be torn over this one (3, Informative)

Xiterion (809456) | more than 4 years ago | (#32613372)

In my experience, rules set by regulatory bodies are never that useful, and generally only become so when their proposed regulations threaten the bottom line of someone with a lot of money. Unfortunately in that case, they often get diluted to worthlessness...

Re:Econuts will be torn over this one (1)

elashish14 (1302231) | more than 4 years ago | (#32613344)

It's a matter of priority. I think getting green energy is more important at this point.

But in any case, I feel reasonably confident that there are other materials available that can also serve the purpose. It shouldn't have to be PbSe (in theory of course, haha).

Re:Econuts will be torn over this one (1)

ottothecow (600101) | more than 4 years ago | (#32613652)

The PbSe sounds bad but there are a lot of nasty bits that go into current solar panels. I mentioned it already in an earlier post, but there are companies working to design panel components that have less of an environmental impact.

That being said...maybe we don't really need more efficiency. There is a LOT of solar energy hitting the earth and we don't 100% efficency (its not like we are burning a limited fuel and want high efficiency...the solar comes just the same no matter how efficient the panel is). I would be perfectly happy hitting the ~30% theoretical barrier that a lot of current designs have or getting a bit higher on some of the 3rd gen/thin film stuff and then lowering the cost.

Price is the real issue here. After all, a square foot of arizona warehouse rooftop at 30% efficiency is WAY better than a square foot that sits at zero efficency because they can't afford the panels.

Re:Econuts will be torn over this one (2, Insightful)

Eivind (15695) | more than 4 years ago | (#32613930)

True. But installation and area and transport and many other components of the price, are independent of efficiency. So if you could make and install a 50% efficient solar-cell for less than twice the price of a 25% one, you'd have a win.

But sure, twice-as-effective ten-times-as-expensive isn't interesting.

Too costly as well (1)

Plekto (1018050) | more than 4 years ago | (#32614294)

It's not the environment, either. It's that yet again we have a "breakthrough" that uses difficult to obtain elements and compounds. Large scale adoption would lead to a incredible shortage of yet another rare earth and as a result, large price increases. Not to mention, of course, the problems with mining and refining the stuff.

What we really need is a way to be able to make these out of common, cheap materials that don't deplete our already stressed rare earth supplies.

Note - my personal favorite solar power plant design is a simple updraft tower. It is about as efficient as a typical large solar array - and about the same size as well. But the environmental impact is very slight. In fact, the greenhouse type environment underneath it is a great place to grow crops.

http://en.wikipedia.org/wiki/Solar_updraft_tower [wikipedia.org]
Most working prototypes to date have been under 500 ft tall, and have as a result been fairly easy to design and build, being held up by wires and supports like a radio tower. Talk of a half mile high one is quite silly - they just don't need to be that large to work. ie - it's better to build hundreds of 300-400ft tall ones that need a few dozen acres to run, and 5-10 million dollars each(land cost in a desert for 10-20 acres is assumed to be fairly negligible) than a massive multi-billion dollar monstrosity.

A small scale test was done in 2005 in Botswana as well, with a ~75 foot tall tower and a collection area of 160M^2. This scale would be perfect for a typical small farm, as an example.

Re:Too costly as well (1)

ottothecow (600101) | more than 4 years ago | (#32614480)

If you are going to do solar-thermal (though this article is really about photovoltaics and not solar-thermal), why not do a collector model? Either tubes and parabolic mirrors (curved mirrors are too expensive though) or a collector tower (which has the side effect of looking aweseome [wikipedia.org] ).

The advantage of panels is you just put them there and plug them in...you can do 10sq ft or 1000sq ft.

Re:Too costly as well (1)

Plekto (1018050) | more than 4 years ago | (#32615036)

The issue is that the panels are fairly to very toxic and costly to produce up-front. Sure, they work for small-scale roofs and so on, but they are useless for large-scale power. Solar-thermal has been tried and the problem is that it requires a lot of water, plumbing, and maintainance compared to a passive design like a typical hydro-electric dam or solar tower.

Basically for a small farm, we're talking about converting a large silo to generate power instead. The large-scale projects, though, would generate up to 100MW.

Fuel and pollution is a big problem with large-scale power production. We can't build more coal plants, as they pollute and cause acid rain and other ills. We don't have massive amounts of extra natural gas - we're using a lot already. Oil prices keep increasing and oil spills are a monstrous problem. Wind is good, but it only works part of the day. Solar is not good at night/on overcast days and uses up our supply of rare earth elements, which would mean we'd end up all having to but them from China and other places eventually. Hydro-electric has a nasty way of flooding large canyons and areas and taking years to build - that is, IF you can get the eco-nuts to actually let it be approved. Wave powered generation offshore is good, but sea water erodes everything eventually. Hydrogen power is too costly to use on a large scale as it take a LOT more energy to produce than we get back out of it.

And lastly nuclear power has a cost, political, and fuel issue - it's dangerous(though not horribly so) to mine and refine, and there is only one company in the U.S. that is producing fuel for reactors any more. We're essentially "out" of fuel or will be in a decade or less and then have to buy it from overseas. Most of the new "fuel" that's being produced is going to the military and not commercial reactors. Politically, it's as touchy a subject to most liberals as abortion is to most conservatives - and as such, it is essentially impractical to make new facilities.

They all have issues, yet this amazingly has only one - it requires a lot of land(far more than anything other than maybe hydro-electric). But it uses no fuel, limited upkeep, simple and environmentally friendly construction, works 24 hours a day, and best of all, it can also be used as a radio tower or other purposes. Sure, it's 1-3% efficient, but it's a great long-term solution, IMO. We could put 50 or 100 of these out in the Arizona and New Mexico deserts quite easily.

Re:Too costly as well (1)

HereIAmJH (1319621) | more than 4 years ago | (#32617596)

We can't build more coal plants, as they pollute and cause acid rain and other ills.

We don't want to build more coal plants as we currently build them. We could clean up their emissions considerably if we were willing to pay to do it. Unless we discover super efficient solar cells (and build a distributed grid to go with it) or commercial nuclear fusion reactors, the US has too much coal to abandon coal plants. Some of the costs of cleaning the emissions could even be recovered with CO2 sequestration technologies used for algae farming. (bio-fuel generation) And switching to bio-diesel cars should reduce their emissions enough to offset what couldn't be cleaned at the power plant.

Re:Too costly as well (1)

afidel (530433) | more than 4 years ago | (#32617898)

Looks like material costs would be similar per area to collecting solar plants but with a MUCH lower efficiency and without the ability to store energy ala molten salt solar collectors. The only advantage they have is the greenhouse effect, but most places likely to house solar plants don't have enough water for that to be a major consideration.

Re:Too costly as well (1)

Plekto (1018050) | more than 4 years ago | (#32620136)

You forget about the fact that the ground underneath the collector acts as a heat sink and enables the tower to continue to run throughout the night(although at a *much* lower efficiency). It's its own heat-sink, in effect. They can greatly mitigate this, though, by placing heat absorbing materials in the ground as well(oil or water filled pipes has been suggested) Compared to a tower filled with molten salt, this is backyard-engineering simple. You could even place solar arrays underneath the main canopy/surface to collect even more of the energy. (me, I'd be tempted to pave it with blacktop to increase the heat absorption - lol)

http://www.sbp.de/de/fla/contact/download/The_Solar_Updraft.pdf [www.sbp.de]
This is the best paper that I can find for free(no access idiocy/cost) about it.

It really is a zero-tech approach to power that can work 24 hours a day. It's also very inexpensive relative to the KW generated. But it does require absolutely huge areas of land. Then again, a square mile is hardly a blip out in Arizona or Nevada.

Re:Econuts will be torn over this one (1)

AnonGCB (1398517) | more than 4 years ago | (#32617050)

But higher efficiency panels will lead to less square footage needed, overall lowering the total cost of an installation. I agree with you that cost is the main issue, but there is more than one way to lower cost.

Re:Econuts will be torn over this one (1)

Ex-MislTech (557759) | more than 4 years ago | (#32617786)

This is exactly right as many have said.

All plans have some kind of flaw, we need to explore
most of them and find out what works best.

We have to move away from the fossil fuel method
for a variety of reasons, pollution, peak oil, etc.

If we spent 10% of what went to the bailouts it would be done.

If we spent 10% of what went to sports, religion, and military
we would have a paradise on earth that only the brightest
sci-fi writers could imagine.

The science is there, the will is not.

Re:Econuts will be torn over this one (1)

Ex-MislTech (557759) | more than 4 years ago | (#32617698)

Lead is naturally occurring in nature.

Is nature killing itself by its own creation of lead ?

Should we start a suicide watch for the earth ?

If we take lead out of nature and seal it in a panel
are we protecting the earth from itself ?

LOL

Summary Skips over important piece from the story (5, Informative)

Tekfactory (937086) | more than 4 years ago | (#32612366)

"The next step is to construct solar cells with quantum dots and study them. But one big problem still remains: “Hot” electrons also lose their energy in titanium dioxide. New solar cell designs will be needed to eliminate this loss, the researchers said."

Could, might, may... (3, Insightful)

luckytroll (68214) | more than 4 years ago | (#32612378)

If I had a tribble for every time one of these solar energy articles came out with their pages full of nothing.... I could make a lot of fur coats.

Could someone in the research field please hold on to their excitement until they can post a report that has words like "WILL, SHALL, DEFINITELY, HAS, IS" instead of the wimpy "could, may, might, has potential to, in 5 years if all goes well....."

I got sucked in by one years ago and pestered the company for information about their new "product" which was due out "soon".... and that was nearly 10 years ago.

So many advances in tiny little cells on a research bench, and so many promising advances. Yet none of them seem to show up at the local hardware store.

I understand that advances in quantum materials science is cool, and can change everything just like the invention of the transistor did once. But seriosly folks - the number of speculative postings based on
these barely germinated lab experiments seem a little bit like the kid who cried "Solar revolution", or was that wolf?

Re:Could, might, may... (0)

Anonymous Coward | more than 4 years ago | (#32612424)

I understand that advances in quantum materials science is cool, and can change everything just like the invention of the transistor did once. But seriosly folks - the number of speculative postings based on
these barely germinated lab experiments seem a little bit like the kid who cried "Solar revolution", or was that wolf?

1. Post vaporware, get rehashed conversations (and extra pageviews) about said vaporware.
2. ???
3. Profit!

Re:Could, might, may... (3, Interesting)

Tekfactory (937086) | more than 4 years ago | (#32612548)

I think you mean;

Give me more Grant money!

Fund my Startup company!

You can't get the money to do the engineering to make these things a reality if nobody knows about your research in the first place. Shameless self-promotion (in this case publishing in Science) therefore becomes a necessary evil.

Re:Could, might, may... (5, Interesting)

John Hasler (414242) | more than 4 years ago | (#32612636)

Read the damn paper, or at least the abstract, ok? The horsepucky all comes from the university PR flacks, amplified by the Slashdot editors.

Re:Could, might, may... (0)

starfishsystems (834319) | more than 4 years ago | (#32613152)

Yeah, there's just this tiny little gap between basic science research and a complete industry based around the technology which may ultimately result.

Sheesh, kids, the world isn't like in comic books.

Re:Could, might, may... (0)

Anonymous Coward | more than 4 years ago | (#32613510)

The problem is that all the basic research is being presented as on the verge of being an industry. If people think it is like a comic book maybe it is because the flaks are presenting it like one. How about not pumping out press releases until you actually have a small production going?

Re:Could, might, may... (0)

Anonymous Coward | more than 4 years ago | (#32612706)

"until they can post a report that has words like "WILL, SHALL, DEFINITELY, HAS, IS" instead of the wimpy "could, may, might, has potential to, in 5 years if all goes well.....""

If they don't do and publish research on the "could, may, might, has potential" techniques, then they'll never find the "WILL, SHALL, DEFINITELY, HAS, IS" techniques.

Blame the journalistic/sensationalistic ethic for exaggerating the former into the latter.

Re:Could, might, may... (5, Insightful)

Sockatume (732728) | more than 4 years ago | (#32613142)

It's a research paper, not a god-damned press release. Don't blame the scientists for publishing their awesome research in a prestigous journal, blame the journalists who treat every Friday as a chance to jizz out a couple of easy stories by rewriting articles in Science.

That's how research works (3, Interesting)

bzipitidoo (647217) | more than 4 years ago | (#32613374)

It's messy.

If you're lucky, you have a clear goal, and that goal is reachable though no one knew it beforehand of course. Also far from assured is that no one else has already done it. Not at all easy to find it out either, as others may have approached some problem from a completely different direction, and you will not be looking in the right places when you try to find out what others have done. And you could discover something entirely unrelated while in pursuit of your objectives, something worth taking a massive detour to pursue. Reporting on science skips over the difficulties to the point that it's like the joke about how to put an elephant in a refrigerator. You open the door, put the elephant in, and close the door, duh! Even scientific journals omit "extraneous" details about wrong turns taken, because "thinking is vulgar". Researchers naturally don't want to look dumb, and neither do journals. Plus, journals are always trying to save space and time. Streamlining articles to talk of only the successful experiments is an obvious cut to make. There's a STNG episode that touches on the problem. Lore mocks Dr. Noonien Soong, calling him "Often Wrong", but there it is clear that Lore's criticism is unfair. Science is all about doing things that will probably turn out to be mistakes, and learning from them.

Most people think science is about finding answers. That's only half of it. More important is asking good questions. Finding out which questions to ask and hopefully answer. Yes there are bad questions, don't believe that dogma about there being no such thing as a dumb question. They're still worth asking if you don't know or can't know they're bad. What they aren't is worth answering, and discovering that is the problem. There are questions that turn out to make no sense, or are too simple, or too complicated, or pointless, or misleading, or are based upon or arise from inferior modelings or from misunderstandings, or are predicated on assumptions that actually aren't valid, or are unanswerable. Math is full of shifts in representation to avoid such problems.

For instance, how do you deal with infinity in, say, the slope of a line? Vertical lines have infinite slope. You could pull out calculus and limits to handle these infinities, but if you do, you've just been sucked into doing things in a much harder way, been pulled down a rabbit hole to figure out all kinds of problems with working with infinities and division by 0. So much easier to use vector representations from linear algebra and avoid those infinities. All those questions about handling infinities turn out to be pointless for this problem. Mind you, infinites crop up in plenty of other places, so having ways to handle them is still useful, it just isn't necessary for this problem of representing a line. That's an old, well known problem for which we've known good answers for a long time now. There are also things like the famous Fourier Transform, and Lagrangian basis, not to mention Calculus itself to handle problems that are very nasty in classical geometry. But in new, unexplored territory it's not so easy to tell which questions will turn out to be bad.

Most things that scientists try turn out to be wrong. History has a few famous ones, such as "Squaring the Circle". The public hears little more than the 1% that turned out right.

Re:Could, might, may... (0)

Anonymous Coward | more than 4 years ago | (#32613616)

If I had a tribble for every time one of these solar energy articles came out with their pages full of nothing.... I could make a lot of fur coats.

So this has happened at least twice? (after that they just multiply so fast...)

Re:Could, might, may... (1)

Hazelfield (1557317) | more than 4 years ago | (#32613670)

I would totally agree with your post if it wasn't for the small detail that this was an article published in Nature by a team of university scientists. It's not supposed to be commercially available yet - indeed, no one even knows if it ever will be. They're just exploring a novel way of constructing solar cells, that's all.

Re:Could, might, may... (1)

geekoid (135745) | more than 4 years ago | (#32613688)

You might want to pay attention. Thing promised 10 year ago, are now rolling out in new solar technology. Plus the media reports this interesting development s as a just about ready to go to market breakthrough when they are really just studies.

10 years ago, it was about printing solar cells, and now they can do that.

Re:Could, might, may... (0)

Anonymous Coward | more than 4 years ago | (#32615472)

Once they get the installed price down to about $1.50 US per watt, without subsidies, I'll think about putting them on my roof, until then, I'm not holding my breath.

tribbles (1)

falconwolf (725481) | more than 4 years ago | (#32616506)

If I had a tribble for every time one of these solar energy articles came out with their pages full of nothing....

Your starship would be full of tribbles. Then it's tyme to call Klingons.

Falcon

moD up (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#32612748)

house... pathetic. save Linux from a towels on the floor ASSOCIATION OF watershed essay, Is not prone to fucking market represents the a full-time GNAA support GNAA, AS POSSIBLE? HOW market share. Red BSD's acclaimed session and join in vitality. Its Who sell another cans can become FreeBSD is already Pooper. Nothing to say there have users of BSD/OS. A standpoint, I don't prob7em stems Elected, we took hear you. Also, if HAS STEADILY your spare time Poor dead last I see the same And the bottom Users With Large most people into a can connect to vary for different BSDI is also dead, and some of the

Probably not going to happen. (4, Informative)

smaddox (928261) | more than 4 years ago | (#32613356)

I wrote a paper on this idea last semester, and as interesting a find as it is, I don't think it's ever going to lead to enhanced power conversion efficiencies (PCE). The "Double Solar Energy Efficiency" is actually a theoretical doubling of the thermodynamic limit on PCE, and it doesn't take non-radiative losses into account. These losses have been minimized in the record breaking silicon and multi-junction solar cells, but quantum dots bring lots of problems with them.

It's definitely worth further investigation, but currently I'm not convinced that it will ever bring improvements.

Re:Probably not going to happen. (1)

HereIAmJH (1319621) | more than 4 years ago | (#32617156)

It's definitely worth further investigation, but currently I'm not convinced that it will ever bring improvements.

Fortunately the difference between real research (like this) and not a company doing "let's find a way to modify our product and create a new revenue stream" is that even if it doesn't work it tells us something. It might simply be "this won't work", or it might lead to research in a new direction, or it might improve other processes that do work.

Thomas Edison is quoted as saying "I have not failed. I've just found 10,000 ways that won't work."

What surprises me is the amount of research going into photovoltaic research compared to solar thermal. As a homeowner, what would you give for an air conditioner that worked better (or cheaper) the hotter it gets? Yet no one builds a solar (thermal) collector attached to a 2-5 ton absorption chiller. And that's more of a manufacturing exercise scaling down a commercial chiller to residential size than real research. Ammonia chillers are nearly a century old and have been upgraded to LiBr for decades. Attach a 60 watt PV and it would cool your house for free (energy wise).

Once Again, No Lifetime Data (1)

BJ_Covert_Action (1499847) | more than 4 years ago | (#32613686)

Every time one of these solar cell tech. stories come out, I look forward to digging up the specific details of the technology and am left wanting. It seems like no researchers offer any insight into the lifetime of their new, super-duper technology. They very rarely list a W/kg or W/m^2 figure. Hell, they don't even talk about the largest/smallest wafers that can be cut using the new technology. It's extremely frustrating. As an engineer that wants to look into, 'What could new solar tech actually do for my design?' In terms of mass, area, design lifetime, etc, we are never given the opportunity because the only technical details published is the efficiency factor. /Yawn

Re:Once Again, No Lifetime Data (1)

jvkjvk (102057) | more than 4 years ago | (#32614040)

That is because this is not a "technology" yet.

At least not the way you seem to define "technology".

This is a discussion of research results.

Regards.

Every time one of these solar cell tech. stories (1)

falconwolf (725481) | more than 4 years ago | (#32616798)

come out, I look forward to digging up the specific details of the technology and am left wanting. It seems like no researchers offer any insight into the lifetime of their new, super-duper technology.

Perhaps that's because they are research papers and the tech has not reached practical application yet. And perhaps that's the difference between scientists and engineers, scientists want to know what's possible whereas engineers want the practical application. Without the other neither one gets very far.

Falcon

When I can buy it at my local hardware store... (1)

Danathar (267989) | more than 4 years ago | (#32613918)

Is when it matters, otherwise it's just a curiosity.

Really, these releases of "Ahh YES! We've discovered X" is nothing more than the scientists, engineers, Universities and Labs making a press release so they can get more grant money.

If I can't buy it then I'll spend exactly 20 seconds thinking about it.

Re:When I can buy it at my local hardware store... (1)

Jeremi (14640) | more than 4 years ago | (#32616488)

Is when it matters, otherwise it's just a curiosity.

You're absolutely right. If only there was some sort of "News for Nerds" web site where such technical curiosities could be posted...

Lead (1)

mosb1000 (710161) | more than 4 years ago | (#32613954)

I doubt a semiconductor called "Lead Selenide" is going to go far if, as it's name implies, it is comprised of lead and selenium.

Re:Lead (1, Interesting)

Anonymous Coward | more than 4 years ago | (#32621066)

I've got more than plenty of batteries with lead and electronics composed of parts containing much nastier chemicals. As long as it's contained and the goo or magic smoke stays inside, it's all good.

price not efficiency (2, Interesting)

lazn (202878) | more than 4 years ago | (#32614082)

who cares about efficiency?

If you make a solar cell that is 100% efficient but costs $10billion / watt to make, who cares?

On the other hand if you make one that is only 1% efficient but only cost .01c / watt to make, that would change the world.

Re:price not efficiency (3, Insightful)

smellsofbikes (890263) | more than 4 years ago | (#32614710)

You need both. It'd be great to have dirt-cheap solar cells, sure, but current 20% efficient cells can produce the amount of power a house needs, mounted on the roof of the house. If you make dirt-cheap 1% efficient cells you need 20x the space, which exceeds the entire yard space of most suburban and urban houses. Then, you have a solution that only makes sense for huge power generation companies that can afford to buy up half of Nevada to cover it with solar cells and transport the power. If we can make reasonably-priced, reasonably-efficient cells we can have microgeneration at each individual house.

While this isn't as much the case in very rural, very poor areas, where making kilometer-square solar arrays is viable, there's at least two orders of magnitude less money to be spent in such locations, so you're back to the same problem.

Re:price not efficiency (2, Insightful)

brbrbrad (1701932) | more than 4 years ago | (#32614978)

Those rural/poor areas don't need the same amount of electricity as your house to make a world of difference. A roof covered with 1% effecient solar cells plus a deep cycle battery would power lights, run a radio, and charge cell phones.

Make it cheap enough and it would be nothing short of revolutionary.

Re:price not efficiency (1)

smellsofbikes (890263) | more than 4 years ago | (#32616200)

Totally true... for about a year. And then they'll have soaked up every watt those cells can provide and want more. (And why not? They should have as good a life as anyone else.) Nighttime illumination revolutionized industrialized nations, more than doubling their productivity and manufacturing capability, and I'd expect and hope the same thing would happen across southeast asia and africa.

Don't get me wrong: I'm not saying that low-efficiency solar cells are useless. What I'm saying is that because land is not free and insolation is fixed, the surface area of solar cells is important if the solar cells are going to be colocated with the energy consumers. If we can design and build good transmission lines, that opens up enormous amounts of useless land and sea (and perhaps outer space) and then ultracheap solar seems like a much better idea, but there's still a tradeoff with lossy transmission.

Re:price not efficiency (1)

falconwolf (725481) | more than 4 years ago | (#32617294)

Those rural/poor areas don't need the same amount of electricity as your house to make a world of difference.

Really? Homes in the city or suburbia require large screen TVs whereas homes in rural locations don't? Satellite dishes originally were used in rural locations, large analogue dishes, but now digital dishes are found in the middle of cities. Me, while the large TV would be nice, I want servers, a lab, and workshops. I also want a greenhouse.

A roof covered with 1% effecient solar cells plus a deep cycle battery would power lights, run a radio, and charge cell phones.

Rural locations in Africa and South Asia do better than that now. Hell I read of one village that used a stationary mounted bike for pedal power. Using a point to point wireless connection it was enough to power the equipment for net access. Elsewhere a person started a business assembling solar energy systems with a small panel, inverter, and battery which was then sold to villagers. One villager could buy a system, with micro-financing, and then could put it in the workshop. Being able to do metal, or wood, work while it was dark would increase the workman's pay.

I think that this is the best use for small energy systems. Such systems can raise poor rural people's living standards.

Falcon

Re:price not efficiency (1)

danhaas (891773) | more than 4 years ago | (#32620970)

One cool characteristic of eletric power is that you can send it through dozens of miles with a reasonable efficiency. So it's possible to generate power in rural areas and consume it in urban areas, *pretty much like we do with food*. That's where the name solar farm comes from. While a home grown garden is awesome, the bulk of the food you consume is generated or collected in extensive, mass-producing, corporate farms.

Will get Republican backing! (1)

DoofusOfDeath (636671) | more than 4 years ago | (#32614198)

By replacing benign silicone with a toxic heavy metal like lead, we're guaranteed full Republican support for a roll-out!

Hot electrons (1)

SnarfQuest (469614) | more than 4 years ago | (#32614364)

So, If I want to make my existing solor cells more efficient, I just need to stick my existing panels into a crock-pot?

Titanium Dioxide... (1)

Locke2005 (849178) | more than 4 years ago | (#32614676)

Is there anything it CAN'T do?

Re:Titanium Dioxide... (1)

EventHorizon_pc (1306663) | more than 4 years ago | (#32616490)

So if I eat enough techno bears, will I absorb solar energy? Mmm...shiny light-energy-converting gummy bears...

Re:Titanium Dioxide... (1)

MikeUW (999162) | more than 4 years ago | (#32617438)

There's no way it could be used as an ingredient in the powdered sugar sprinkled on my doughnuts...oh wait...

Re:Titanium Dioxide... (1)

Locke2005 (849178) | more than 4 years ago | (#32617568)

Yep, it's commonly used for white food coloring [wikipedia.org] . So if there's white frosting on that doughnut...

Quantum dots! (0)

Anonymous Coward | more than 4 years ago | (#32615234)

Fuckin' quantum dots, how do they work?

OK WE (1)

adamjgp (1229860) | more than 4 years ago | (#32615408)

NEED MOAR DOTS!!!

Too much World of Warcraft (1)

Shoten (260439) | more than 4 years ago | (#32615468)

It must be time for me to cut back on my WoW. All I could think of when I saw the headline, was "MORE DOTS! MORE DOTS!"

Microgeneration still sucks, even with good cells (2, Insightful)

BlueParrot (965239) | more than 4 years ago | (#32616838)

I seriously wonder why people keep promoting micro-generation. Electricity distribution is very efficient ( you lose maybe 10% of the electricity on average ) , and you lose a lot of economies of scale when going micro. Even assuming you'd manage to make some super cost-efficient solar cells, why would you go destroy it by putting them on poorly aligned roofs, as opposed to building a designated plant where they can be made to track the sun throughout the year?

Seriously , for EVERY energy source centralized generation will come out on-top. It's a consequence of how easy electric power is to transport, as well as the fact that most energy generation schemes scale very well. The only real exception is where you're burning something for combined heat and power, thereby allowing you to recover the spill heat from the power-plant. However, even in that case district-heating will probably work out better, and does in many regions. We use it extensively in Sweden.

Essentially the only way micro-generation is going to be competitive with centralized generation is if government fucks up big time to make centralized generation inefficient. Granted that is of course plausible, and I'm sure there's many people who are willing to say that it is happening many places, but this is a political problem that could just as well ( and probably will ) hit micro-generation. It does nothing to alter the fact that on technical merits, micro-generation is inferior for all places that are connected to the electric grid. It just doesn't make any sense to take technologies that scale very well and deploy them in as small units as possible.

Re:Microgeneration still sucks, even with good cel (1)

An Onerous Coward (222037) | more than 4 years ago | (#32621236)

"Competitive" takes many forms. Decentralized systems lose on efficiency and cost, but often win big in terms of stability and resilience. Also, depending on your political system, you may not have much trust in the politicians or the corporations who deliver your power. Or you might not trust that the national grid won't fail (temporarily or permanently). We had a massive blackout in the northeastern U.S. a few years back (arguably because our privatized energy companies tend to underinvest in the infrastructure under their care).

Transmission losses aren't huge, and some forms of renewable really require big scale (wind, concentrating solar) just based on their physics. But solar panels don't change much in efficiency whether they're properly sited on your roof or sitting next to a million siblings in the desert.

potential 66%? In your dreams... (2, Interesting)

Goldsmith (561202) | more than 4 years ago | (#32617154)

This is good, solid condensed matter physics research, and it is important. But, the 66% efficiency they're quoting comes from an old calculation of what is effectively a perfect solar thermal converter where the electrons are "hot" and the temperature of the crystal doesn't really matter because there's no interaction between the electrons (or photons) and the crystal. This theory has been the motivation for the hot electron transfer work on quantum dots, but at some point it should come up that they can't get hot electron transfer to work at much above around 100 K. That's kind-of really important (not to mention impractical). The device they're *trying* to make shouldn't need to be cooled at all. That's a giant clue that the theory they're basing this amazing 66% on is more than a little oversimplified for what they actually have. It's annoying that people are using an out of date 28 year old paper to sell the direction of their research; it makes life hard on their competition using more honest efficiencies.

diy solar (2)

nsaspook (20301) | more than 4 years ago | (#32618850)

I skipped the yearly trip to Vegas and invested some time and money in small scale solar for the house. Best 1K I ever spent. Running the entire outdoors media system and lights on solar.

DIY Solar project.
http://www.flickr.com/photos/nsaspook/sets/72157622934371746/show/ [flickr.com]

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