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Pliable Solar Cells on a Roll 241
klevin writes "New Scientist is running a story on someone else who's developed thin, flexible, photovoltaic cells: 'The thin and bendy solar panels can be stuck to fabrics, sheets or backpacks and promise a go-anywhere electricity supply.' Whatever happened to those sheets of solar cells that some university here in the US developed several years back? As I remember, the concept was that they could be draped across roof-tops and whatnot. Never heard anything after that." We had post about solar building clothing last year.
Hmmm. (Score:2, Insightful)
Not really (Score:3, Interesting)
Re:Not really (Score:2, Informative)
Weight is the key... (Score:3, Informative)
Here's a few links (thanks Google and the obligatory Wikipedia):
A geocities-looking [solarsails.info]
Re:Not really (Score:2)
you'd be generating electricity at the cost of momentum. If the sail absorbs the photons to make electricity it can't reflect the photons to make motion.
Re:Not really (Score:2, Informative)
Re:Not really (Score:3, Insightful)
Re:Not really (Score:2, Insightful)
At "a little thicker than photographic film", it is probably too heavy to be a good solar sail material.
(Yeah, I know you never said it would, but you do seem to be defending that position.)
Re:Hmmm. (Score:2)
solar sails need to be incredibly light and (as a consequence) thin.
solar sales work on light pressure not by converting light to electricity to drive an engine.
Re:Hmmm. (Score:4, Interesting)
Just use the solar cells to power up a linear accelerator and shoot nuclei out the back at near the speed of light. If you can get 0.999c from a nucleus you get a tremendous thrust for one little atom. Remember, F mA when you approach the speed of light. Relativity rockets (super ion engines) are probably the best means of propulsion where electric power is plentiful but mass is dear. I'm sorry, but that tiny momentum of a photon is so small it is pathetic. Granted you get 2x boost for reflection vs 1x boost for adsorbtion, but 2 x 0 still equals 0. The only way to practically get around in space is to shoot nuclei out the back of a rocket engine at the speed of light.
Re:Hmmm. (Score:2)
The problem is that energy efficiency of space drives (i.e. how much kinetic energy ends up in the vehicle, rather than the exhaust) is inversely proportional to the speed of the exhaust.
So, nuclei at 0.999c are very much *less* energetically efficient than chemical drives or normal ion drives; atleast unless you intend to travel at *very* high speeds- as in interstellar travel rather
Re:Hmmm. (Score:2)
Re:Hmmm. (Score:3, Informative)
For the laymen out there, I'll explain this in technical terms. If you have a roughly cylindrical quartz crystal, and if you squeeze it, the crystal lattices "snap" into an alternative arrangement which free's up some electrons and essentially produces a static charge. When you remove the stress, the crystal lattice snaps back into its rest state and wants its electrons back.
Conversely, by applying
Re:Hmmm. (Score:2)
Well a little piezoelectric tutorial can't hurt anyways :-)
Are there other applications besides clothing? (Score:3, Insightful)
I think this type of material could be very useful to provide electricity in places that do not have access to a reliable electrical grid.
How many watts are needed to run a a phone, a refrigerator, a radio or a computer?
Re:Are there other applications besides clothing? (Score:2)
Re:Are there other applications besides clothing? (Score:2)
Re:Are there other applications besides clothing? (Score:2)
"if you can see" - well, technically, yes, but the dynamic range of the eye is amazing. The difference in the amount of energy you could get in dim light (say, just enough to read by) and the amount in full sunlight is so enormously large that the former might as well be zero. Even in fairly good light (e.g. under a 60W bulb 2-3 feet away) the amount of energy you can practically recover is very small (enough to run a calculator, not much more). Even with full sunlight and high efficiency, you still need
Re:Are there other applications besides clothing? (Score:2)
Solar cells are already used in lots of applications that don't have access to an electrical grid, reliable or not. Pliable solar cells might be useful in more applications, but the ones we have now are used quite a bit.
What applications, you might ask? `35 mph school zone' lights (it's easier to add solar cells than to run wires.) Remote creek monitoring stati
Re:Are there other applications besides clothing? (Score:2)
It takes about as long to charge the battery (while still using the computer) as to exhaust the battery so i'd imagine the power consumption of the laptop itself is about half this.
Regarding the mobile phone. My charger has a rating of less than 7W, and i usually need to charge it for about 2.5 hours every 3 days. This is very manageable with solar cells (you have 72 hours to accumulate 21 watt-hours of energy).
For a fridge, it's a lot/right on the yellow label (Score:2)
for non-US readers, we have nifty governmental regs that require yellow energy consumption labels on the side of most kitchen appliances, that include likely annual operating costs, to allow the consumer to make a better informed choice...
I can see it now (Score:2, Funny)
WARNING (Score:3, Interesting)
Re:WARNING (Score:2)
Re:WARNING (Score:2)
WARNING! DO NOT USE WHILE BATHING OR WHILE HAVING SEX
I think that warning is pretty redundant for most people around here...
Re:WARNING (Score:2)
Uh, we already have those. They're called "dark colors". Direct light to heat conversion. Very efficient.
Mod Parent +Funny (Score:2)
True, I did hear it here first.
But I couldn't help myself -- I laughed.
-kgj
Re:WARNING (Score:2)
or you can just wear a black shirt and skip the whole electricity part.
Iowa Thin Film Technologies (Score:2, Informative)
Flat vs. Flexible Info (Score:5, Informative)
Thin, flexible cells have been around for a while. One reason they haven't caught on heavily is because they're nowhere near as 'powerful' (efficient at conversion) as hard panels. Did a quick search (don't take this data *too* seriously, but it represents what's normal); compare panels from these two pages:
Flexible [solar-electric.com]
Solid [solar-electric.com]
Specifically, compare "Unisolar 32 watt flexible solar panel" from the first link to "Shell ST40 thin film CIS 40 watt solar panel" on the second. The flexible panel is 940 sq. inches and 32 watts, while the solid panel 663 sq. inches and 40 watts. Big difference in watt per area.
I ended up choosing a big solid one to fit in the rear dash of my car; flexible would have been easier to deal with, but it won't fold, and produces less power. (I use the panel in my car to power my laptop/cell phone combo while camping and stuff, it's very cool and gets a lot of questions from random interested people!)
Here's another chart to compare the two: Product Page [selectsolar.co.uk]
Tried to find an efficiency rating chart comparing the two types, but no luck. The numbers are out there somewhere...
Re:Flat vs. Flexible Info (Score:2)
Re:Flat vs. Flexible Info (Score:5, Informative)
Cheers, Ulli
Mod Parent +Informative (Score:2)
Interesting link, very relevant -- thanks!
-kgj
sweet! (Score:2, Funny)
Re:sweet! (Score:2)
Cheap solar panels (Score:2, Insightful)
The major impact of this tech has nothing to do with its portability/flexibility. The article estimates that the price for a final process fab will be about 1 euro per watt, compared to a highly competitive market which has so far only produced 5.6 euro per watt glass panels.
Simply put, this would make photovoltaics as an energy source an order of magnitude more competitive, if the process is scalable.
Re:Cheap solar panels (Score:2, Interesting)
Still, 1 euro per watt would make a HUGE difference in the viability of solar.
Re:Cheap solar panels (Score:2)
Solar Cells on a Roll (Score:4, Funny)
Now matter how pliable or environmentally friendly, solar cells are not good on a roll. They taste absolutely nothing like butter, and quite frankly, I find them barely palatable.
Don't the editors try this these things themselves? This is as bad as that "http://slashdot.org/article.pl?sid=02/10/28/1852
Re:Solar Cells on a Roll (Score:2)
Is $US52 per square metre about right? (Score:4, Informative)
They quote 7% efficiency, 1 euro per watt.
Full sun is 1000 watts/sq metre, so with 7% efficiency we get 70 watts/square metre, so it has a cost of 70 euros/sq metre or, at 1.33 euros to the dollar, about $US52.60/sq metre.
Cover a 10 * 4 metre area of roof for $2,100 and get enough energy, in the middle of summer, to boil your 2 kw electic kettle all day.
At 12c per kwH for electricity, @ 2.8 kw * 6 hours/day * 365 days/year gives a cost saving of $735 pa, or a repayment of the $2,100 capital in 3 years
Are these numbers OK?
At this price will it be practical to disconnect from the grid sometime soon?
Re:Is $US52 per square metre about right? (Score:2, Informative)
thank you, my error, cost around $US93 /sqm (Score:2, Insightful)
Thank you, so a cost of $93 sqm making close to $4,000 to cover 40sqm, or a repayment time of 6 years. Not so good, They won't get you to disconnect from the grid
Re:Is $US52 per square metre about right? (Score:5, Informative)
The rule of thumb I came across when I was studying the econ of solar cells ~18 months ago was that for thin film cell solar to be viable (without govt subsidy) it had to be manufactured for $1/pW (or one euro, depending on exchange rate) and had to have at least 10% efficiency. If the 10% efficiency is not met then the downstream costs eat you alive because you have to install so much more area of solar cells to get the required power.
The current advances in flexible solar have been excellent and the solar market is growing at ~30% (although still >90% c-Si cells), but unless you are willing pay a price to be "green" or your govt gives you a fat subsidy for installing the solar power it will take you many years to repay your capital - on the order of 10 or more if you currently have ready access to the power grid. If you are remote from the grid, solar is actually a great deal cheaper today - but by using Si-based solar which is manufactured on relatively large scale today and has 15% efficiencies versus thin film.
Govt subsidies are still going strong in Japan - Germany is wavering. With G(lobal) W(arming) Bush in office the increase in solar in the US is going to be from the Eco-minded willing to take a bath $$-wise or off grid applications - well, there are also cats who are pretty good at utilizing passive solar power.
Re:Is $US52 per square metre about right? (Score:2)
I'm going to have to agree with drphil on this one. I myself have three cats, and they're extremely well versed at passively utilizing the solar power entering through the window.
12V DC - Can solve this with old technology (Score:2)
You don't necessarily need to run much or any through a rectifier and lose power that way.
Forty-five years ago my parents had a 12V DC generator, they still have a pile of 12V bulbs and other bits. 12V DC lighting has improved a lot since then, and there are a lot of appliances (including refrigerators) that run off 12V DC. Your computer lives on 12V, some LCD screens can too. Buying a whole lot of stuff that runs o
Prefab Solar Roofing (Score:2)
Good questions. Answers, anyone?
-kgj
www.oksolar.com/roof/ (Score:2, Informative)
Mod Parent +1 Informative (Score:2)
Thanks!
-kgj
Re:Is $US52 per square metre about right? (Score:2)
In Albequerque, New Mexico, the yearly average (taking into account both day *and* night, when the sun doesn't shine at all), is actually only about 250 watts per square meter. So you're already off by a factor of 4. Move to a city like Seattle, which is a lot farther north (less sunlight) and w
Re:Is $US52 per square metre about right? (Score:3, Informative)
The next factor to consider is the solar insolation [solarseller.com] for your area. This tells you how many hours of direct sunlight you get, for your area, each day. In my case, the annual average is about 4.5 hours / day.
At that rate, 1 kW of photovoltaics will give me about 4.5 kWh of electricity, per day, on average.
Also in my area, electricity is about 7 cent/kWh. Consequently, that 1 kW PV array will save me about 31.5 cents/day, on ave
Energy Rich Desert (Score:2)
Um, that's the situation right now -- Saudi Arabia, scorching hot desert, energy rich, no other resources. (Or did I miss your irony?).
-kgj
Re:Energy Rich Desert (Score:2)
I believe the Luxor hotel (the one shaped like a Pyramid) is covered in Solar Cells to power the beam of light that shoots into the sky they have on at night.
If I had my own house instead of an apartment, I'd love to cover it with solar cells. We get around 12 hours or so of sunlight every day, even in the winter.
I also wonder how much it would take of these to keep a battery charged in a car. It could further improve gas milage on hybrid cars (at least dur
Solar Luxor (Score:2)
I believe the Luxor hotel (the one shaped like a Pyramid) is covered in Solar Cells to power the beam of light that shoots into the sky they have on at night.
Vegas itself is a monument to excess, but Luxor is synonymous with pure luxury. Those Pharaohs sure know how to live!
I live in Minnesota, our sunlight situation is not so, um, bright. We're making some headway with agrofuel and wind, but relatively little, and there are problems.
-kgj
Re:Energy Rich Desert (Score:2)
No, I'm not forgetting the oil -- I refer to it implicitly:
"Saudi Arabia, scorching hot desert, energy rich, no other resources."
-kgj
Re:Energy Rich Desert (Score:2)
It reads:
"I look foreward to a time when countries that whose only natural resourse is large amounts of scourching hot desert and they are considered energy rich."
Okay, I mis-read his statement. Easy to do, let's read it again:
"
This fits Saudi Arabia perfectly: Scorching desert, considered energy rich.
But of course, the kicker is Matt's preface: "I l
Re:Energy Rich Desert (Score:2)
Got it, makes sense.
I was thinking of Saudi Arabia, after the oil runs out.
-kgj
Snow is also annoying (Score:2)
Is this different... (Score:2)
I can buy them at canadian tire, thats how common they are. Product # 11-1575-0 for example. (might neet to enter a postal code, v1p1c7 works.)
Maybe they are more efficient or something? These seem about the same as a rigid solar panel for the size. More expensive though obviously.
FINE, I just looked at the article..seems the only advantage is th
Re:Is this different... (Score:2)
I've got my north wall wallpapered with an OLED screen broadcasting a white image and my south wall wallpapered with solar panels to catch it all.
I hereby claim prior art for all the future perpetual motion/infinite energy machine creators who attempt to patent my brilliant idea.
Spheral Solar Power in Canadian Tire... (Score:2)
http://www.atsautomation.com/solar_technologies/d e fault.asp [atsautomation.com]
SSP as mentioned on Slashdots pior story for having solar "denim" has small flexible solar panels avaliable now in Canadian Tire. Not that this helps those of you not in Canada... But you can buy them now.
Price per watt is what matters (Score:2)
I always thought that a cool thing to do would be to use the excess electricity from PV cells to crack water and make Hydrogen gas rather than goofing
Re:Price per watt is what matters (Score:2, Interesting)
Re:Price per watt is what matters (Score:2)
Hooking up to the grid is both tricky and lossy. You must feed in a synchronous AC signal which is in phase with the grid. Typically you would use a DC->AC motor/gen
Re:Price per watt is what matters (Score:2)
Maintenence is an issue of course, nothing is perfect in this world.
Re:Price per watt is what matters (Score:2)
There are two key price points;
Cheaper than a consumer can buy electricity,
and cheaper than the electric company can make electricity.
From the f
Electricity is only a small part of the game (Score:3, Interesting)
Whereas the collection of Heat is as simple as it can get, but rarely used.
Though most mediteranian countries use solar heat for heating their domestic water, but that is about it.
What i have in mind is the use of solar heat, collected during summer, to warm domestic homes during winter. (Thats where real amounts of energy (read CO2) are needed !)
Water is an exellent storage container for heat and is dirt cheap.
The only problem is where to store all the warm water. Probably the easiest solution would be to pump up ground water, heat it, and pump it back. (The ground is actually an exellent therman insulator!)
Use the 1kW of solar energy from a couple of M2 of these cells to make water run through 100 m2 of cheap solar heat collectors.
Now we are SAVING evergy.
Re:Electricity is only a small part of the game (Score:5, Interesting)
Now you just need a near perfect insulator and your all set. (say an underground tank insulated with airogel)
The real trick isn't in just heating homes though. It's also running things like ovens and stoves. For that your going to need a liquid that stays a liquid between -10c and 250c, without dangerous pressure build up, freezing, corroding or screwing up your pumps. (and it can't pollute the environment when it leaks)
Once you can safely transport high temperatures 2-3 times boiling point, you can do some pretty amazing things. Like running your A/C from the heat well. (two sterling engines hooked up to eachoter in reverse) Water pumps, air tools, and electrical generators (40-50% efficient in sealed systems like sterlings, but much higher for open ended boilers. The trick as you put it is to avoid converting the energy from one form to another untill it's absolutly necesary.
Re:Electricity is only a small part of the game (Score:2)
than have water run by it to heat up the central heating, but never reaching the boiling point.
This all with enough safety, that any moron can have one in the basement?
I think the hot water soultion looks simpler. probably not as efficient, but safer the least.
s.
Re:Electricity is only a small part of the game (Score:2)
Re:Electricity is only a small part of the game (Score:3, Funny)
Re:Electricity is only a small part of the game (Score:2)
Solar Power on the Go (Score:2, Insightful)
It spends a lot of time out in the sun.
But my clothing?
I don't spend nearly as much time in the sun as my home does
Cheers,
-- The Dude
Mr. Solar (Score:2)
Flexible solar cells have been available for years (Score:2)
Solar power? (Score:2, Informative)
Re:Didn't RTFA, but... (Score:2)
"Kroesen's team has made its solar cells bendy simply by making them thin. But this has involved a trade-off. While the best solar cells are now working at efficiencies above 20%, the H-AS cells are only about 7% efficient. The researchers think efficiency is worth sacrificing for a cell that is going to be more generally useful, though they still hope eventually to reach 10% efficiency."
Re:Didn't RTFA, but... (Score:2, Informative)
This is the best plant chlorophyl (sp?) systems can get. It is also sad but true that it is extremly rare that machines, silicon or other, significantly out do nature in efficiancy.
HOWEVER, since the average solar energy hitting earth is 1.4 kW/m^2 that means that even at 50% we are taking in 700 w/m^2. Now since the average energy use for a home is 17,130 kw/h that means we will need an average of 24-25 square meters to power a house.
Then of course the
Re:Didn't RTFA, but... (Score:2)
Re:Didn't RTFA, but... (Score:2)
I wonder how the efficiency of these panels compares to the more conventional ones. I can't help but think that there's probably a difference; but if it isn't too bad, they could prove to be pretty useful.
At the moment it's around 7% which is a little bit lower than conventional solar cells which have an efficiency of around 20%.
But they are working to get it to 10%.
Second, they can produce it for 1 a watt.
Which means that it's 8 to 10 times cheaper than conventional solar cells.
Re:Didn't RTFA, but... (Score:2)
I hate to correct you on costs per watt: currently is between $3.50 and $5.30 per watt, dependind if you buy 1 module or 100,000 modules.
Current prices of photovoltaic cell modules is always tracked at a nice website, http://www.solarbuzz.com/Moduleprices.htm [solarbuzz.com].
Half the cost (55%+) of a solar cell installation is dc->ac conversion & associated electronics. this development does not help that cost, unfortunately...
--Kevin
--> Shameless Plug: I'm looking for a Sr. Software Engineer Job in Northw
Re:But what will the Terrorist implications be? (Score:2, Insightful)
Re:But what will the Terrorist implications be? (Score:2)
Re:But what will the Terrorist implications be? (Score:2)
You first, of course.
Re:But what will the Terrorist implications be? (Score:2)
Good day to you.
Re:But what will the Terrorist implications be? (Score:2)
Two words: Not funny.
Good day to you.
Same : )
Live in Caves (Score:2)
Sorry, no can do.
All the good caves are already taken, by guys in robes with long beards, whose names I can't pronounce.
-kgj
Re:But what will the Terrorist implications be? (Score:2, Insightful)
It didn't say it was ultra-powerful, it says it was thin and cheap in trade for efficiency (and possibly usefulness)
A truly inventive person can use anything to any purpose. Don't fear the technology, fear the people using it. If we abandoned all technology used by terrorists, we'd be living in caves and the government would be licensing the use of fire, wheels, and hammers.
-- guns don't kill people, kids playing video games kill people
Re:But what will the Terrorist implications be? (Score:2, Funny)
Re:Bendy (Score:2)
Wonder... (Score:2)
Could you grab a roll and keep it round the house, then just cut strips off and make things with it?
And 1 euro per watt... WTF? How many cubic meters of fabric in a watt exactly?
Re:Wonder... (Score:2, Funny)
A4=0.0625 m^2 IIRC
So 1m^2=144-160W
Add suitable number of pinches of salt.
Alternatively find out how efficient regular solar panels are and reduce the power output by 50-65%.
Re:people are missing the point (Score:2)
Re:people are missing the point (Score:2)
Since Infra-Red radiation is part of the electromagnetic spectrum and very near the wavelengths of visible light, can it be focused using an optical lens just as one can focus light rays?
I had an idea about placing a fresnel lens in front of a large low-availability IR radiating source and focusing it to make a hotspot. A small area with an extremely high temperature is much more thermodynamically useful
Re:people are missing the point (Score:2)
Paul.
Re:people are missing the point (Score:2)
Re:people are missing the point (Score:2)
The best conventional (fossil fueled) steam turbine power plants are something like 30% efficient. That compares favorably with the best solar cells available, s
Re:Highways (Score:2)
Nice try but you get what you pay for. Sucking electromagnetic energy from moving vehicles would only result in vehicle drag, resulting in worse fuel economy, resulting in faster depletion of preci
I'm not so sure of that... (Score:2)
An engine is most efficient when running at close to wide open throttle at (relatively) low RPMs. Most people like to accelerate harder than an engine that at achieves this at highway speed will allow. Combine that with varying loads, (Most cars have just one person in them, but the engine is sized for all seats full, luggage, and a trailer) and it would be an advantage to use induction to pull energy from most cars - IF you can control the amount gathered from each car.
I don't if this makes up for all
And you can buy them (Score:3, Informative)