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Carbon Nanotube Solar Cells On the Horizon

timothy posted more than 4 years ago | from the on-the-horizon-they're-closest-to-the-sun dept.

Power 150

MikeChino writes Carbon nanotube news abounds as of late, and the next application for the up and coming material may be hyper-efficient and economical solar cells. Led by professor Paul McEuen, researchers at Cornell recently tested a simple solar cell (called a photodiode) crafted from a single carbon nanotube. Surprisingly, researchers discovered that more light shined on the nanotube created even more electricity, a huge difference from today's silicon solar cells where excess energy is lost in the form of heat rather than used to create more electricity."

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The technology isn't important (3, Insightful)

davidwr (791652) | more than 4 years ago | (#29504049)

The question is, it it cost-effective?

New title:

More cost-effective Solar Cells On the Horizon

There, fixed that for you.

Re:The technology isn't important (3, Insightful)

Anonymous Coward | more than 4 years ago | (#29504175)

The question is, it it cost-effective?

New title:

More cost-effective Solar Cells On the Horizon

There, fixed that for you.

New solar cells that are "more cost-effective" require new technology.
New technology requires research.
Research is an expensive process.

To make new, more cost effective solar cells, we need to fund _some_ technology. Carbon Nanotubes are promising.
Press releases get a college department more funding, which buys new equipment and affords more people working on a subject area.

So, in short, the fact that this technology is related to Carbon Nanotubes is intrinsically important.

Re:The technology isn't important (2)

bugnuts (94678) | more than 4 years ago | (#29504333)

Considering the energy required to produce crystalline Si cells, if the manufacturing is perfected, it could be both more efficient and cheaper. A solar pv panel today must produce energy for a year or two to recover the energy used to create it. Nanotubes may be much more complex, but they probably need nowhere near as much power to create.

The bottom line Is what generally matters to consumers, but the cells must still be efficient because roof real estate is not unlimited.

Re:The technology isn't important (1)

mapsjanhere (1130359) | more than 4 years ago | (#29504903)

It's a great finding, but unfortunately, making nanotubes is a HIGHLY energy intensive process, and you will still need some form of substrate to connect these - most likely silicone. To really utilize this effect they have to find that you can get the effect from a macroscopic sheet of woven or non-woven CNTs, or they have to learn how to grow the tubes from one electrode to the other, which isn't trivial.

Re:The technology isn't important (2, Funny)

camperdave (969942) | more than 4 years ago | (#29505047)

Yeah, but you can buy tubes of silicone at any hardware store. It ain't exactly rare.

Re:The technology isn't important (2, Funny)

drseuk (824707) | more than 4 years ago | (#29505519)

It's a great finding, but unfortunately, making nanotubes is a HIGHLY energy intensive process

Obviously we need someone to invent some sort of hyper-efficient, clean and renewable energy source to power the manufacturing process then.

Re:The technology isn't important (1)

werfu (1487909) | more than 4 years ago | (#29506211)

Then use produced Solar cell and install them on the top of the factory so the energy for manufacturing the next one will come from the sun.

Re:The technology isn't important (1)

show me altoids (1183399) | more than 4 years ago | (#29504751)

One important application where efficiency (and durability and lifetime, but that's another story) trumps cost-effectiveness by a wide margin is powering satellites and spacecraft, though. So there is room for more than one technology in the mix, depending on the application.

Re:The technology isn't important (5, Funny)

kheldan (1460303) | more than 4 years ago | (#29504789)

The question is, it it cost-effective?

If someone developed a 99% efficient solar cell, would you really care what it cost?

Re:The technology isn't important (3, Insightful)

Idiomatick (976696) | more than 4 years ago | (#29504977)

Yes... that's stupid. Of course it matters what it cost.

Re:The technology isn't important (0)

Anonymous Coward | more than 4 years ago | (#29505989)

At any price it'd be a steal at only half the cost--and they are only charging double that!

Re:The technology isn't important (1)

Brigadier (12956) | more than 4 years ago | (#29506925)

Perhaps, but I promise you this, at 99% in an energy starved world where energy is one of the driving forces for tension between countries, and world dominance (see middle east and russia) cost becomes much much less important. at $10.34 per kw/hr I assure you no matter what cost you charge there will be investors out there who will finance you.

Re:The technology isn't important (1)

Idiomatick (976696) | more than 4 years ago | (#29506999)

no.... if it costs 10x current solar prices to ramp it up to 99% then it doesn't really help does it. I mean maybe for some weird science use but not for energy production.

Re:The technology isn't important (2, Interesting)

Lloyd_Bryant (73136) | more than 4 years ago | (#29508517)

no.... if it costs 10x current solar prices to ramp it up to 99% then it doesn't really help does it. I mean maybe for some weird science use but not for energy production.

TFA is a little light on details, but consider this quote: "Researchers discovered that more light shined on the nanotube created even more electricity, a huge difference from today's silicon solar cells where excess energy is lost in the form of heat rather than used to create more electricity."

So say it's 10x the current price of solar cells, but can utilize cheap mirrors so that you only need 1/10 as many of them as conventional solar cells.

There *is* some potential here (assuming it actually works on a larger scale, of course).

Re:The technology isn't important (2, Informative)

Da Fokka (94074) | more than 4 years ago | (#29505199)

If someone developed a 99% efficient solar cell, would you really care what it cost?

You're kidding right?

For everyone who is looking for real solutions (unfortunately that's not quite everyone in the debate), the cost is a crucial factor in the equation. Economic efficiency is more important than energy efficiency.

Re:The technology isn't important (1)

Dare nMc (468959) | more than 4 years ago | (#29505567)

Economic efficiency is more important than energy efficiency.

they are both fairly important. As stated above, if your launching this into space for a satellite then the Economics is vastly different than if you putting this next to a nuclear plant. If we could just convert a nuclear plant into a dedicated solar cell manufacturing plant, get rid of all the ugly & terrorist target & high maintenance of the power grid, all the middle men (IE Enron, etc) in favor of wal-mart, that changes overall economics greatly. Adding $50,000 to the cost of a Prius to have a permanent solar charge that fits into the roof, I would have to pass. Adding $70,000 to a high end motor home, that then never needs fuel, grid connection, etc. Even if it just provides say 500 miles of travel a week + complete self sufficiency (ok I still probably need to recycle the waste for clean water) Is well worth considering (would trade my house in as a down payment.)

Re:The technology isn't important (1)

jeffb (2.718) (1189693) | more than 4 years ago | (#29506125)

Adding $70,000 to a high end motor home, that then never needs fuel, grid connection, etc. Even if it just provides say 500 miles of travel a week + complete self sufficiency (ok I still probably need to recycle the waste for clean water) Is well worth considering (would trade my house in as a down payment.)

Good luck with that. A 20% efficient panel will collect maybe 1 KWh/m^2 over the course of a mid-latitude day, on average. A typical motor home will have somewhere around 15 m^2 of roof area. That means you can collect 15kWh per day with today's panels. That's enough to run an electric motor at 20HP for a bit less than an hour. Or, looking at it another way, that's about the energy you get from burning half a gallon of gas.

This is all from the back of a pretty small envelope, as it were -- your panels won't be oriented optimally toward the sun, but you could also cover the sides and ends, so the total-power-intercepted figure shouldn't be too far off. An electric power train is a lot more efficient than an IC engine and power train. But, bottom line, it's not going to be practical to run an RV on any conceivable solar arrangement, unless it's got big dragonfly wings covered with panels, which would run afoul of DOT regulations.

Re:The technology isn't important (1)

Khyber (864651) | more than 4 years ago | (#29506745)

For one, 15kWh is about the average amount a three bedroom house uses in a day. That RV would move just fine off of that, and it could still have huge 'dragon wings' as you know, most RVs have those things called hinges that allow those huge shade spreaders on the sides of RVs to fold against the side of the RV while it is in motion. The only problem would be camping in a forest where a majority of sunlight gets blocked. More efficient solar cells made from this technology would pretty much allow truly solar-powered vehicles.

Re:The technology isn't important (1)

jeffb (2.718) (1189693) | more than 4 years ago | (#29507319)

For one, 15kWh is about the average amount a three bedroom house uses in a day. That RV would move just fine off of that...

...just not for long.

Most people don't seem to realize that the typical vehicular engine can produce much more power than the typical household electric service. A generous 200A 240V feed equates to about 64 horsepower. At that power level, you consume 15kWh in a bit less than 20 minutes.

Looking at it another way, an RV will typically get around 10 mpg. That means you're using about 3.3kWh of gasoline per mile (energy content of gas is about 33kWh/gal). Assuming you lose about 80% of that to thermodynamics and other losses not present in an electric power train, you'll still need something like 0.8 kWh per mile, giving you a range of maybe 20 miles per day. And that's neglecting all the other things you'd like to do with the power you collect.

The fold-out panels hold promise; see the comment below.

Re:The technology isn't important (1)

Dare nMc (468959) | more than 4 years ago | (#29506847)

The thread was more of a hypothetical 99% efficiency what would the value be... It appears with nano tubes a reflector has a bigger benefit, so we could get 20% over not only the panel area, but the reflector area as well. 10meter x 2.2meter motor home roof, with a full length vertical reflector on each side that could automatically rolled out to say 5 meters while parked, tracking the sun would give me 22 m^3 of panel area + 50 m^3 of reflector area (assuming we can choose the optimal parking direction.) with just one reflector panel up at a time we could be close to the 75kwhr@20% efficiency. I could see a 100 hpHr per day, with enough batterys to store that for the week, I could see moving that large of a motor home 60 MPH @ 100HP * 4Hr = 240 miles a week, and still using 1/2 the power for personal non motoring use (make night runs when no traffic, and maximize reflector use by day.)
I think my point is the convenience of not worrying about power (other than a "lets relax another day") in high luxury doesn't need to make the same economic sense to the same degree as a factory just trying to cut costs.
The solar panels on the roof couldn't stay flat, but maybe just a single hinge allowing a full 90 degree tilt and if absorbed solar from both sides, could get this well over 75 m^3, even at difficult sun angles.

Re:The technology isn't important (1)

jeffb (2.718) (1189693) | more than 4 years ago | (#29507519)

Yes, this idea of putting down roots and spreading out petals during the peak of the day could buy you quite a bit. However, it also imposes a much greater requirement for batteries, which brings us right back to the other disappointingly stagnant technology. If only we could come up with a high-power-density battery system with a service life much greater than the current few hundred to few thousand cycles, a lot of things would get a lot better.

The best power density I see for current commercial technology is less than 150 Wh/kg. That means the batteries to store 75kWh of energy would weigh half a ton. If you want a week's worth, that's 3.5 tons, about the weight of, well, a motorhome [ukandeuropetravel.com] .

Re:The technology isn't important (1)

kheldan (1460303) | more than 4 years ago | (#29506255)

they are both fairly important..

You see my point; If, say, a few square feet of your roof can supply all of your daily electricity needs for the next 20 (or more) years, then what's that worth to you? If a dozen acres of otherwise useless land can supply a city the size of New York, then what's that worth? Naturally the cost of any technology goes down over time as manufacturing processes are perfected and optimized, and as more manufacturers are producing that technology.

Bad examples (1)

Dare nMc (468959) | more than 4 years ago | (#29507361)

I can put a dollar value on those easily, and they better make financial sense, little else matters. In the US Cars are generally a 2-3 year investment, and a house is a 5-8 year thing, both generally financed. Both (as a guy) require me to grab a calculator and figure out the math (because it won't change my lifestyle/activities.) And given the choice of eliminating a $150 per month utility bill at the cost of a $300 mortgage will be obvious (same with the car.) The same isn't true about lifestyles, hobbies, security, fun. So a luxury item isn't scrutinized to the same degree. That was why the motor-home analogy, it is a luxury item, it is also a lifestyle changing item throw in a hobbies/fun factor (bring out the toys!!!) Now it is only a matter of "can I afford it?", if yes count me in.

Re:The technology isn't important (1)

Artifakt (700173) | more than 4 years ago | (#29506811)

The problem with that is, Economic Efficiency is a non-stable and non-quantifiable metric. Trying to calculate economic efficiency results in absurd conclusions.
        In the real world, such calculations have 'proved' that the United States doesn't need high speed cargo rail, it just needs to keep subsidising the airlines. It's 'proved' that shipping from say, Nice to Tuniz by truck, through nations such as Lebanon, in time of war, is 'better' than shipping straight across the sea by blimp. It's 'proved' that communications sattelites could never be successful unless only done by various governments. It's 'proved' that putting small tiles on the belly of your space-shuttle instead of casting large sections could never possibly cause an accident worth getting excited about.
        In more abstract situations, a professional cost accountant will tell you quite literally that NO consequence is bad enough to make you not take an offer, IF the consequence occurs far enough in the future. If a new chemical process will make billions in the next few years, but render all mammalian species totally sterile 200 years from now, we should do it, because the negative consequences are so remote, no matter how devastating or inevitable.
        This was once pointed out by John W Campbell Jr. back in the early 1950's. He put some extreme scenarios to several economic efficiency experts and had them use their usual mathematical tools to analyse just how much immediate profit would justify taking the offer, with accompanying Campbell selected long term consequences described as inevitable. Every one of the subjects found some level of immediate profit that made the offer a good one even though the long term outcome was something such as putting everyone over age 50 into a meat grinder, shooting all males of our species, or other such horrible ultimate outcomes. Several of the respondents said they were only willing to let him have their results because they believed no one would actually act on them, or something else would intervene before we had to pay out. Five of them put something in their responses to the tune of "Thank God Hitler's dead so there's nobody crazy enough to actually try this". (Hope that doesn't Godwin the thread).
        Buckminster Fuller has written quite a bit about why realistic economic rules would always include either energy efficiency or total energy budget values, and from what I gather, he generally expected both were vitally important in all but a few degenerate calculations.
       

Re:The technology isn't important (2, Insightful)

jonadab (583620) | more than 4 years ago | (#29507965)

> Economic Efficiency is a non-stable and non-quantifiable metric.

There are limits to how precisely it can be pinned down, but some arrangements are obviously more reasonable than others.

> In the real world, such calculations have 'proved' that
> the United States doesn't need high speed cargo rail,

That conclusion is correct. The problem with any railroad is that it's only practical when huge amounts of cargo (or passengers for that matter) need to travel exactly the same route all the time. We do use it for things like taking coal to steel mills, but delivery speed doesn't matter there. A high-speed cargo rail would have VERY limited applicability in the United States. If you're from Europe or southern California, you might really have a sense of this until you drive across the Midwestern US in a car a couple of times. Put simply, only a small percentage of our cargo starts or stops at a major city.

> it just needs to keep subsidising the airlines.

That's a separate issue and not significantly related to the rail question. The airlines mostly handle passenger traffic and mail. Almost all cargo goes on eighteen-wheeled semi trucks, because they can deliver to any destination.

> It's 'proved' that shipping from say, Nice to Tuniz by truck,
> through nations such as Lebanon, in time of war, is 'better'
> than shipping straight across the sea by blimp.

Any kind of reasoning can fail of the person applying it fails to take important factors (such as war, for instance) into account. That's neither here nor there.

> NO consequence is bad enough to make you not take an offer,
> IF the consequence occurs far enough in the future

That's a straw man, and not a particularly clever one. Nobody in the history of the universe has ever seriously argued in favor of doing anything that they knew would destroy their entire race a couple of centuries down the road. Nobody. Ever.

Economic efficiency *does* matter for solar cells, and ones that are cheaper to manufacture (for any given level of energy output) are better, and such research is important, because if the solar panels can pay for themselves in a year and continue producing energy for ten or twenty years, people *will* buy and install and use them; whereas, currently most people are not buying or installing or using them, because they don't produce enough energy to pay for themselves fast enough to cover the opportunity cost of whatever else people could buy with the same money.

I don't know whether these nanotubes will lead to the kind of solar cells that are really needed, or whether it's a blind alley. The researchers don't know that either. But in the absence of any knowledge of a *better* technology, it's worth exploring the possibility.

Re:The technology isn't important (1)

Socguy (933973) | more than 4 years ago | (#29508531)

Boys, let's not argue! Cost vs efficiency are both important, it's your application that determines which is more so. If you're planning to launch the things into space, the purchase cost is not going to be terribly important to you but if you're planning on selling solar accent lights through Wal-mart then you want the cheapest cells that you can get your hands on.

Re:The technology isn't important (1)

fifedrum (611338) | more than 4 years ago | (#29505239)

could a 99% efficient solar cell even provide enough electricity to cool/warm/light my home? Of course, but how large of a setup would one need?

Let's see.

according to http://www.wunderground.com/calculators/solar.html [wunderground.com] I have no idea what I'm talking about.

How much electricity do I need in my home? http://tonto.eia.doe.gov/ask/electricity_faqs.asp [doe.gov] says the 2007 average was 936 kWh per month. I'll say I'm average in that respect with a gas furnace and clothes dryer.

that's 11,232 kWhs per year?

At my location, upstate NY on a line from Buffalo to Albany, at 99% efficiency, I would need one 10'x10' panel to generate 13,938 kWhr/year.

So, there you go, Yes, I would like one 12'x12' 99% efficient solar cell (larger than I need, to cover for growth and storing for a rainy day), and really, the cost is important so I would like it for free.

Re:The technology isn't important (1)

jonadab (583620) | more than 4 years ago | (#29508099)

Yeah, but someone living in northeastern Ohio would probably need about ten *acres* of solar cells to meet the energy needs of an average household, unless you can provide enough batteries to store the summer excess to last all winter. (In the fall and winter, NEO can go *months* without direct sunlight, so your panels would be running on the diffused ambient light that filters down through the cloud cover, which is typically about half as bright as a normally-lit indoor room.)

99% != infinite (1)

jeffb (2.718) (1189693) | more than 4 years ago | (#29505559)

If it costs less than 10 times as much as a 10%-efficient cell, I'm all over it. If it costs 100 times as much, I have no interest, unless I'm really constrained for space and/or weight, or installation costs per square meter are really high.

No, wait. If "99% efficient" means only 1% of the incident radiant energy gets past it or gets re-radiated as heat, I'm all kinds of interested. But, of course, that's not ever going to happen.

Re:The technology isn't important (1)

TooMuchToDo (882796) | more than 4 years ago | (#29505603)

If I have 100 sq miles of land I can cover with solar panels, do I care how efficient they are if they're dirt cheap?

Re:The technology isn't important (0)

Anonymous Coward | more than 4 years ago | (#29506755)

Sure you care. Look at the cost and resistive losses associated with wiring 100mi^2.

Re:The technology isn't important (1)

Beezlebub33 (1220368) | more than 4 years ago | (#29508667)

As well as the installation, maintenance, and hail damage costs associated with a large area installation.

Most people in this thread really need to understand something about lifecycle costs. If solar panels were completely free, it still would not make sense for most people to install them on their roofs, because of all the other costs.

Re:The technology isn't important (2, Funny)

Aceticon (140883) | more than 4 years ago | (#29505949)

Well, if somebody developed a 150% efficient solar cell I wouldn't care about cost.

Then again, you could use such a solar cell to power some high efficiency light producing device (say, a LED) which you would point at the solar cell thus getting back more energy than you used to power the light (i.e. free energy).

Re:The technology isn't important (1)

CrimsonAvenger (580665) | more than 4 years ago | (#29505985)

If someone developed a 99% efficient solar cell, would you really care what it cost?

Yes, I would. If it cost $1,000,000 for enough solar cells to generate 1 kilowatt at 99% efficiency, it would be essentially worthless for anyone but NASA.

What I'm looking for is something that costs $1,000 per kilowatt. That's cheap enough that I could actually make use of it.

Re:The technology isn't important (1)

efalk (935211) | more than 4 years ago | (#29507343)

Absolutely. If it costs more than twice the price of 50% efficient cells, then its usefulness is limited to a few weight or surface area -critical applications.

Re:The technology isn't important (1)

henryhayne (650298) | more than 4 years ago | (#29507523)

It does not matter about the costs, because even if it were 100% efficient it would require huge tracks of land to replace our current energy sources. That in itself would be more damaging to the environment than the current fossil fuel problems. Only Geothermal and nuclear power offer environmentally sound approaches to replacing fossil fuel.

Re:The technology isn't important (1)

hesaigo999ca (786966) | more than 4 years ago | (#29505597)

I guess that would also depend on how much more efficiency we gain through this method.
I think the present state is 30 to 40% or something minimal like that...if this shot it up to 80-90% then I think regardless of cost, the same panel would yield you twice as much power...just let's hope it does not cost twice as much to produce.

Re:The technology isn't important (1)

Locke2005 (849178) | more than 4 years ago | (#29506141)

The question is, is it complete bullshit from a clueless moron?

researchers at Cornell recently tested a simple solar cell (called a photodiode)

I'm not a Cornell researcher, but I'm fairly certain a solar cell is not the same thing as a photodiode. Once again, proof that the only way we can make science relevant again is to train the people reporting on it to actually understand what the hell they are talking about!

Re:The technology isn't important (1)

Artifakt (700173) | more than 4 years ago | (#29506949)

A solar Cell is definitely not the same as a Photo(emitting)diode. (and most of the time, when someone says photo-diode that's what they mean). Whether you could justly call a photo(converting)diode a solar cell with built in unidirectional output is really a matter of semantics. I'd go with not conflating the two simply because it's potentially confusing, but then, most people say LED instead of photo-diode these days so maybe the usage is legitimate.

But is it ENERGY-effective? (1)

Errol backfiring (1280012) | more than 4 years ago | (#29506649)

What's even more important: is it energy-effective? In other words, does the solar panel generate more energy in its entire life than it takes to build one? At least for a decade ago, that did not seem to be the case for any solar panel.

Homer says... (4, Funny)

Azghoul (25786) | more than 4 years ago | (#29504083)

Carbon nanotubes... is there anything they _can't_ do?

Re:Homer says... (4, Funny)

Anonymous Coward | more than 4 years ago | (#29504191)

They have yet to get me a date with Megan Fox.

Re:Homer says... (1)

lorenlal (164133) | more than 4 years ago | (#29505579)

Let's be fair, I doubt anyone perusing these forums has either.

Re:Homer says... (1)

TooMuchToDo (882796) | more than 4 years ago | (#29505681)

Michael Bay can work that into Transformers 3. With some more explosions.

Re:Homer says... (1)

Avalain (1321959) | more than 4 years ago | (#29507469)

Though he can only work that into Transformers 3 if he has enough carbon nanotubes.

Re:Homer says... (1)

Locke2005 (849178) | more than 4 years ago | (#29506093)

"Ye cannae change the laws of physics!"

Re:Homer says... (1)

Radtastic (671622) | more than 4 years ago | (#29506803)

That's because your tube, while carbon, is still nano.

Re:Homer says... (4, Funny)

idontgno (624372) | more than 4 years ago | (#29504241)

We need a huge ticker-tape parade for our hero, Inanimate Carbon Nanotube.

Re:Homer says... (1, Funny)

Anonymous Coward | more than 4 years ago | (#29505463)

Wow! Did you actually get to _see_ the nanotube??

Re:Homer says... (1, Informative)

Bovius (1243040) | more than 4 years ago | (#29504519)

Carbon nanotubes can't be mass produced economically.

Re:Homer says... (4, Insightful)

kheldan (1460303) | more than 4 years ago | (#29504841)

Carbon nanotubes can't be mass produced economically yet.

There, fixed that for you.

Yikes, what an article! (3, Interesting)

Maury Markowitz (452832) | more than 4 years ago | (#29504127)

Did anyone else conclude that article was written by someone who had little idea what they were talking about? Note that "light" doesn't enter the description until after they talk about running power through it. And not one number.

Re:Yikes, what an article! (1, Informative)

Anonymous Coward | more than 4 years ago | (#29504269)

I agree, especially with the comment about excess light. Traditional solar cells do in fact produce more "electricity" or current, with higher intensity light. Second, a photodiode is a more complex structure than a solar cell in most cases, since a solar cell is just a P-N junction.

Re:Yikes, what an article! (1)

stokessd (89903) | more than 4 years ago | (#29505035)

A photo diode is just a PN junction too.

Re:Yikes, what an article! (0)

Anonymous Coward | more than 4 years ago | (#29505651)

Photodiodes are also light emmitters, not collectors. The article seemed to be describing some kind of super-efficient electronic PMT, though the science must be different with graphine nano-sheets. Supposedly the carbon nanotubes form a zero-gap semi-conductor somehow, even though the work function of carbon itself is a staggering ~5eV.

That said, heat is typically generated in silicon solar cells by electrons struck by light that doesn't give them enough energy to jump the gap. An externally applied field would give those electrons more energy, and a low resistance zero-gap material would allow them to be carried away before they could recombine. So I can see how these nanotubes might theoretically be capable of converting very high and very low energy photons into electricity...

However, visible light is at about 1eV, so these nanotubes would have to have some mechanism for converting 1eV photons into electricity, other wise it wouldn't matter how efficient they are, since the vast majority of the sun's isolation is visible light.

Re:Yikes, what an article! (1)

swanzilla (1458281) | more than 4 years ago | (#29504405)

No numbers, but they managed to sneak in an exclamation point.

Researchers across the world have attempted to create cells from silicon, plastic and even human hair!

Lacking substance...long on hippy drivel.

Re:Yikes, what an article! (1)

Jeremi (14640) | more than 4 years ago | (#29507947)

and even human hair! [...] Lacking substance...long on hippy drivel.

To be fair, it's only the hippies who had hair long enough to be usable in industrial quantities.

Hyper-efficient + economical (0)

Anonymous Coward | more than 4 years ago | (#29504161)

Neither of these two keywords will ever be available in solar cell tech for private customers. The technology combining these two have existed in several shapes for decades, but the dire reality is that there's much money to be lost in releasing this to the public, and much money to be made in making sure this tech. never reaches the hands of the public market.

Since circa the 60s, when amorphous silicon solar cells became available to anyone, there have been numerous breakthroughs - tried, tested, verified and producable for the same penny - in this field, and still, today, 40 years later, the only thing on the market is just that: inefficient, amorphous silicon, which isn't even cheap.

Ooh, ooh (4, Insightful)

russotto (537200) | more than 4 years ago | (#29504239)

Another world changing technology that's just around the corner.

Re:Ooh, ooh (1)

yancey (136972) | more than 4 years ago | (#29504309)

This didn't sound "just around the corner" because it's pretty basic research and we still need good ways to mass produce the nanotubes. Still, the science there is now proven and it's "just" an engineering problem. Someone fund this... please!

Re:Ooh, ooh (4, Insightful)

H0p313ss (811249) | more than 4 years ago | (#29504601)

Another world changing technology that's just around the corner.

Just for fun, if you're old enough, try to remember what things were like 35 years ago in the mid 70's:

  • The internet was essentially a private network that most of us didn't hear about until the late 80s...
  • No PCs, a portable computer was a dummy terminal PRINTER with a 300 baud modem
  • Cell phones the size of lunch boxes
  • Giant floppy disks with less that 1MB capacity.

These days the average (new) cell phone is more powerful than all the computing resources used by the Apollo program. Heck I carry my ENTIRE music collection around with me every day!

Now try to imagine the world in 35 years.... it's just around the corner.

Re:Ooh, ooh (0)

Anonymous Coward | more than 4 years ago | (#29505009)

I think it's pretty amazing, actually, that a cellphone sized computer could be used to perform (and now, perhaps even automate - as in run an autopilot program) all the calculations necessary to control a spacecraft intended to fly to the moon and back. Granted, the launch vehicles themselves are a bit more sophisticated, but all of that number crunching was necessary to control the thing. Now, your laptop could be the flight controller for the entire American space program prior to the 1980's, and probably with power to spare.

It's hard to say what the future will hold, but people take contemporary technology for granted enough as it is.

Re:Ooh, ooh (2, Funny)

seven of five (578993) | more than 4 years ago | (#29506505)

I think it's pretty amazing, actually, that a cellphone sized computer could be used to perform (and now, perhaps even automate - as in run an autopilot program) all the calculations necessary to control a spacecraft intended to fly to the moon and back.

There's an app for that.

Re:Ooh, ooh (1)

H0p313ss (811249) | more than 4 years ago | (#29507267)

There's an app for that.

You might be aiming for +funny by tapping that meme, but it turns out you're right [lunarmodule3d.com] .

Re:Ooh, ooh (1)

russotto (537200) | more than 4 years ago | (#29508593)

Just for fun, if you're old enough, try to remember what things were like 35 years ago in the mid 70's:

Nuclear fusion was just around the corner. So were high efficiency solar cells. Some things got a lot better. Some things didn't.

Again with the #$##%# solar cells (4, Funny)

McGregorMortis (536146) | more than 4 years ago | (#29504299)

Not a week goes by that you don't hear about yet another breakthrough in cheap and efficient solar cells. Every week, without fail, since 1979, I swear to God. Any more grains of salt, and I'll have a heart attack.

Re:Again with the #$##%# solar cells (1)

MyLongNickName (822545) | more than 4 years ago | (#29504407)

And prices have been dropping. I am only a casual observer, but have seen that manufacturing costs have dropped to under one dollar per watt. I'd really be curious to see a chart of the price drop over the past twenty years, but my google-fu has yet to uncover the information.

Re:Again with the #$##%# solar cells (3, Interesting)

MyLongNickName (822545) | more than 4 years ago | (#29504605)

Here is an anecdote I found in my search

"Scott,
The price of PV modules has come down in the last year, although not quite as much as the Times article suggests. I don't think there has been any significant drop in the cost of inverters, racks, cable, or installation labor.

My first PV module cost me $8.33 per watt in 1980. I paid $3.97 per watt in 2004, and $3.99 per watt in April 2009. Current PV module prices can be as low as $3 a watt, but only if you buy a whole pallet of modules. Otherwise you're still liable to pay $3.50 to $3.96 a watt"

So, since the year 1979 which the GP references, prices to the consumer have dropped more than 50%, even without adjusting for inflation. After accounting for inflation, you are looking at solar being 5 times cheaper than 30 years ago. Not bad.

I know it is poor form to extrapolate like this, but if we had a similar improvement over the next thirty years, then solar would easily become the number one source of energy worldwide. that may or many not come to pass, but the overall point is that despite the jaded responses from folks, we are seeing dramatic improvement in the price/performance of solar.

Re:Again with the #$##%# solar cells (1)

Kokuyo (549451) | more than 4 years ago | (#29505181)

You extrapolate wrong, though. In your own example, the price has actually risen between 2004 and 2009. Even keeping inflation in mind, the price drop during those three years will come out as marginal. So the curve of this price drop has become quite flat, don't you think?

This implies, IMO, that even though manufacturing costs have dropped, the consumer price has not changed all that much. Obviously, someone is finally making a profit... Or rather huge profits all of a sudden, depending on how cynical you want to be.

Re:Again with the #$##%# solar cells (1)

blueg3 (192743) | more than 4 years ago | (#29505223)

The shorter a time period you use for extrapolation (or fewer data points), the more wrong you are. You shouldn't be concluding much of anything from the price trends of the last five years.

Re:Again with the #$##%# solar cells (1)

MyLongNickName (822545) | more than 4 years ago | (#29505363)

Not really. Adjusting for inflation, we are still seeing a 14% drop in five years, or nearly 3% drop annually.

Also, we are discussing one guy's experience. I'd still love to see a more formal chart of manufacturing costs and consumer cost per watt.

Re:Again with the #$##%# solar cells (1)

Idiomatick (976696) | more than 4 years ago | (#29505565)

Firstly, 2006 p/w was 8$ (Before gov rebate). Next, it sounds like a logistic graph though i doubt you could ascribe a curve to it. With much more points I bet you would find big drops followed by period of relatively little change. This may be bounded by a logistic curve.

But solar panels are physically limited. Even if they grab 99% of the energy that hits them and they transfer it cheaply we will still have to make they for almost the same price as sheets of hard plastic. At best solar cells can become what 3.5x more efficient from in use ones (physical limitation) and maybe halve in price (more variable). After you take away government rebate then I think in 50?(huge range with diminishing returns) years we could make solar power cost 1/4~1/5th as much.

Current nuclear technology price per watt is nearing that now. It has much much more room to drop in price. And it is better for the environment than current solar panels. The amount of materials raped from the earth is less. The footprint is much less. Uranium is more common than tin. And there is no hard physical limitation on 'plant' style energy production.

I do think that solar will have its place. But saying it will be our number one if folly. Perhaps is we find a rugged cheap version we could eventually replace shingles with them but I don't expect that any time soon. Use in mobile devices sure... if it is paint-able we could be it more widespread. But they will never replace power plants. In the next 50 years, energy demands are going to spike as people leave gas and maybe coal as well. Nuclear is the only technology that can keep pace with that. Plain and simple.

Re:Again with the #$##%# solar cells (1)

geekoid (135745) | more than 4 years ago | (#29504453)

On the plus side, the cost of solar panel is expected to hit 1 dollar a watt by before the end of 2010, and as cheap as 50 cents a watt by the end of 2012.

Re:Again with the #$##%# solar cells (2, Informative)

Firethorn (177587) | more than 4 years ago | (#29504823)

On the plus side, the cost of solar panel is expected to hit 1 dollar a watt by before the end of 2010, and as cheap as 50 cents a watt by the end of 2012.

Do you have a link on that?

If true, the only thing remaining would be to drop the ancillerary costs to a similar level. Right now that's running around $1/watt itself.

For example, a 6kw inverter [solarhome.org] runs $3.6k. That's $.50/watt right there, without getting into wiring, mounting costs for the panels, paying for the electrician to hook everything up*, etc...

*You can't count on everyone, or even a significant fraction of the population to be able to do this stuff themselves.

Re:Again with the #$##%# solar cells (1)

TooMuchToDo (882796) | more than 4 years ago | (#29505773)

http://solveclimate.com/blog/20071219/1-watt-itunes-solar-energy-has-arrived [solveclimate.com]

A Silicon Valley start-up called Nanosolar shipped its first solar panels -- priced at $1 a watt. That's the price at which solar energy gets cheaper than coal. Curious that this story is not on every front page.

Note that the article is from 2007. What I love about their process is that when they run the roll of substrate faster, the process becomes more efficient. And while you're correct, the support equipment and installation aren't exactly cheap, the panels will continue to come down in price making the total installation cost cheaper.

Re:Again with the #$##%# solar cells (1)

drinkypoo (153816) | more than 4 years ago | (#29506981)

Show me someplace I can purchase nanosolar at even a competitive price, say, $3.75 a watt for finished panels (ready to glue down or whatever.) I can get seconds-quality panels (cosmetic problems, nothing wrong with them) for $2.75 a watt fairly regularly.

Re:Again with the #$##%# solar cells (1)

TooMuchToDo (882796) | more than 4 years ago | (#29507187)

I can't, because their capacity is sold out for the next year or two, which isn't a bad thing. They're available though.

Re:Again with the #$##%# solar cells (1)

PmaxII (1599235) | more than 4 years ago | (#29504475)

But this one is not like the others! It's hyper-efficient.

Re:Again with the #$##%# solar cells (1)

plastick (1607981) | more than 4 years ago | (#29505141)

I totally agree. Article after article and yet we never see a single thing or a single product. I'll believe it when I see it and, until then, it's vaporware.

thanks for this (0)

Anonymous Coward | more than 4 years ago | (#29504451)

wow... nice thanks for sharing....

http://www.techandgizmo.com

On the Horizon? Really (1)

BJ_Covert_Action (1499847) | more than 4 years ago | (#29504609)

FTFA:

Though still in the very early stages of development, if perfected, carbon nanotube-based cells could provide a more efficient method of converting light to electricity....

ans

While the device is certainly in its earliest stages of development...

So it uses a rather exotic material and is still in the "earliest stages of development" but is on the horizon? Really? It sounds to me like we probably won't see them commercially available for at least another 10 years...then again, I suppose the truth of the statement depends on one's definition of, "on the horizon," but I wouldn't expect to be seeing these guys in Home Depot anytime soon...

Re:On the Horizon? Really (1)

blueg3 (192743) | more than 4 years ago | (#29504777)

It's a strange but not rare material -- essentially limitless, but currently expensive to produce.

Re:On the Horizon? Really (3, Interesting)

avandesande (143899) | more than 4 years ago | (#29505885)

The important thing though is that with the linear response to photons light can be focused on the cells- even if they are expensive they could possibly be cost competitive with Si cells.

Re:On the Horizon? Really (1)

sgt scrub (869860) | more than 4 years ago | (#29504927)

The last working test is sitting in an eastern window. Get it? East... Window... Horizon...

Sorry.

Re:On the Horizon? Really (1)

Idiomatick (976696) | more than 4 years ago | (#29505573)

Really, when was the last time you actually MADE it to the horizon, I think the title is maybe cruel but true.

I for one...(obligatory) (0)

Anonymous Coward | more than 4 years ago | (#29504743)

I for one, welcome our Carbon Nano-Tube overlords!

The slow rate of solar cell improvements (1)

Danathar (267989) | more than 4 years ago | (#29504827)

Is it just me or do we get all sorts of stories about this or that breakthrough but I have yet to see ANY of this stuff make it to wide use (or even in specialized cases). What good is all this research if none of it ever gets engineered into something we can use.

Don't get me wrong. I LOVE science and research but I look up in the sky and see that big freaking nuclear fusion ball hanging there and wonder why we can't seem to get enough energy from it.

Re:The slow rate of solar cell improvements (1)

snspdaarf (1314399) | more than 4 years ago | (#29505145)

why we can't seem to get enough energy from it.

It's that 8 minute delay. It kills your efficiency.

Re:The slow rate of solar cell improvements (0)

Anonymous Coward | more than 4 years ago | (#29505583)

well, we are kinda only getting the energy that happens to intersect with earth, and of that only the part that makes it through the atmosphere as light, and of that only about 30-40% at current best makes it into usable energy... I'm sure if we were to encase the sun in a sphere designed specifically to capture all radiation from it, we'd be able to generate as much energy as we'd ever need for a good long while, even if the sphere itself was only 10% efficient.

Re:The slow rate of solar cell improvements (1)

blueg3 (192743) | more than 4 years ago | (#29505587)

R&D takes time. If you want to read articles about scientific developments where you can have engineered results "soon", read publications from 15-20 years ago.

Re:The slow rate of solar cell improvements (1)

timeOday (582209) | more than 4 years ago | (#29505731)

Is it just me or do we get all sorts of stories about this or that breakthrough but I have yet to see ANY of this stuff make it to wide use (or even in specialized cases).

I think what you are seeing is all the progress in solar is masked by the fact it still hasn't reached the critical threshold of being cheaper than fossil fuel. Regardless of whether it's 20 percent more expensive or 20 times more expensive, it's still not the cheapest option. However, it has been making progress and getting cheaper, which fossil fuel is headed quickly in the other direction. (Well, not coal... it's the cheap, plentiful, crystal meth of energy production that may just prove the undoing of our environment).

I for one welcome our new carbon-based leaders... (0)

Anonymous Coward | more than 4 years ago | (#29504861)

I for one welcome our new carbon-based leaders... Oh, wait? They aren't new?

Cool, I can't wait. (1)

dvh.tosomja (1235032) | more than 4 years ago | (#29504879)

Nanotubes solar panel will be looking great on our flying cars. Except, articles like these occured every few month or so. Meanwhile, the only available cells in the real shops are those silicon cells with 14-17% efficiency - just like 50 years ago.

Future speak meets now tech. (2, Insightful)

ZWarrior (194861) | more than 4 years ago | (#29505115)

I, for one, thought the article was good for giving us a look into the future of the tech. Based on teh way things are rapid prototyped and built these days I would expect to see something like this hit the markets in 5-7 years, and the price become reasonable with 2-3 years after that. 10 years to a cheap and cost efficient power source is not bad.

More light = More electricity (1)

MiniMike (234881) | more than 4 years ago | (#29505305)

Surprisingly, researchers discovered that more light shined on the nanotube created even more electricity, a huge difference from today's silicon solar cells where excess energy is lost in the form of heat rather than used to create more electricity.

Great, then we only really need one of these. And one really, really big lens.

Re:More light = More electricity (1)

Tekfactory (937086) | more than 4 years ago | (#29506295)

I know you could be going for funny, but there is a project in Israel that does exactly this they have 1,000x parabolic concentrating reflectors that reflect all their light onto a single PV panel.

http://www.greenmomentum.com/wb3/wb/gm/gm_content?id_content=2365 [greenmomentum.com] The image seems to be missing, so here is the Manufacturers site. http://www.zenithsolar.com/ [zenithsolar.com]

Also this Fresnel Lens gets 1,000x concentration but isn't really a reflector

http://www.technologyreview.com/energy/22204/?a=f [technologyreview.com]

Photoresistive, not photovoltaic (2, Informative)

Ancient_Hacker (751168) | more than 4 years ago | (#29505783)

If you read TFA carefully it seems to be describing a PHOTORESISTOR, not a PHOTOVOLTAIC device.

They talk about APPLYING a potential difference across the thingy, and discovering it has a wide dynamic range OF RESISTANCE, not of any ability to generate voltage or current.

We don't need any more resistors, we have enough of them and they don't generate any power anyway.

This article is even more of a major fail than most.

Re:Photoresistive, not photovoltaic (2, Informative)

Anonymous Coward | more than 4 years ago | (#29506547)

If you read TFA carefully it seems to be describing a PHOTORESISTOR, not a PHOTOVOLTAIC device.

But they describe it as a photo-diode. I'm going to take a leap of faith here and assume they know the difference.

Oh, and here is a link to the original page [cornell.edu] .

Re:Photoresistive, not photovoltaic (1)

Ancient_Hacker (751168) | more than 4 years ago | (#29508107)

>But they describe it as a photo-diode.

Photo-diodes can be used in resistive or voltaic modes. The original page is not any clearer.

In any case it still an answer to a non-existent problem-- photocells do just fine in full sunlight.

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