A Step Closer To The Optimum Solar Cell 107
An anonymous reader writes "Besides cost, solar cell efficiency is the second most critical criteria. Scientists from Berkeley Lab and other institutions, have announced a new solar cell material that may be able to achieve an extraordinary efficiency of about 50 percent -- twice the amount of the current record holder."
This is the last you will hear of this (Score:4, Funny)
Re:This is the last you will hear of this (Score:2, Funny)
Re:This is the last you will hear of this (Score:1, Funny)
They already have these. Check out the salt flat races one day. Some go well over 300 mph actually.
Re:This is the last you will hear of this (Score:2)
Actually, to be honest it's probably the Stonecutters! After all, they admitted to stifling the electric car and adoption of the metric system. And we all know that despite his Oscar-worthy performance in "Three Men and a Baby", Steve Guttenberg wouldn't be nearly as popular...
Re:This is the last you will hear of this (Score:1)
It is a good thing that they keep the Martians under wraps, as I, for one, do not wish to welcome our new Martian overlords...
Re:This is the last you will hear of this (Score:2, Funny)
Re:Three Men and a Baby PG (Score:2)
interesting story, dependance on crystal growth (Score:4, Informative)
"They needed a new material with a 1-eV band gap and a crystal lattice structure that matched the other layers of the cell," Walukiewicz explains. "They used gallium indium arsenide nitride alloys in which just a little nitrogen could achieve the desired band gap, and an almost perfect lattice match."
Since the band-gap reduction was unexpected, Walukiewicz set out to find out how it worked. The answer, it developed, was that the few atoms of nitrogen, which are much more electronegative than the host atoms (much more strongly attractive to electrons) produced a narrow energy band of their own, splitting the GaInAs conduction band into two parts. The gap to the lower of the two conduction bands was the desired 1 eV.
In the case of GaInAs, other characteristics of the split bands made for a poor solar cell material. Nevertheless, Walukiewicz and his colleagues continued to investigate the phenomenon and developed a model of the split-band phenomenon known as "band anticrossing."
Yu admits that forming highly mismatched alloys is "challenging from a crystal-growth point of view," but there is hope that crystals can be grown epitaxially (the growth on a crystalline substrate of a crystalline substance that mimics the orientation of the substrate). One good sign, he says, is that Japanese researchers have already grown thick oxygen-doped crystals of a related material, zinc selenium.
...when I see it (Score:4, Interesting)
But experience generally showed that Breakthrough X which would produce cheap power/double battery life/allow 5 terabytes in my computer never actually arrived at the market.
I'm still waiting for holographic storage from 10 years ago!
Re:...when I see it (Score:3, Interesting)
Re:...when I see it (Score:3, Interesting)
In my experience things get slowly better - anything promising a vast improvement overnight tends to be a little less likely to appear.
Re:...when I see it (Score:2)
without such breakthroughs cpu speeds would have been limited to the numbers they were in the 80's.
Re:...when I see it (Score:4, Insightful)
That's what happened to all the funky things we tend to hear about. We don't all have massively parallel computers because Intel etc didn't all get stuck at 4-500MHz as was predicted some time in the mid 90s.
We don't have holographic storage because, quite frankly, it just ain't worth it when magnetic storage can pack hundreds of gigabytes in a device that is, honestly, about as small as you really need it to be.
If there was a demand for these items, even a perceived one, they'd get produced. But there isn't.
Now, a 50% solar cell...?
Re:...when I see it (Score:3, Insightful)
Now, a 50% solar cell...?
While demand in the alternative energy market is iffy right now, you'll definitely have demand for more efficient photovoltaics at _any_ price in the space industry.
Lifting mass into space is expensive. If you can get a 2-3x improvement in power to weight ratio of your solar arrays using materials like this, the world will beat a path to your door even if you don't have a way to gro
Re:...when I see it (Score:1)
I'm still waiting for my flying cars that where promised in Back to the Future!!
Re:...when I see it (Score:1)
Re: Flying cars (Score:1)
No Solar For You! (Score:3, Insightful)
So not only does it not work yet, but any article that starts off with the words "besides cost..." is obviously talking about an economic impossibility.
We're stuck with cheap oil until it runs out in a few decades. And then we're stuck trying to rebuild civilization with coal.
Re:No Solar For You! (Score:3, Insightful)
Something wrong with nuclear power?
The gap between running out of oil and igniting fusion can be filled with fission based reactors.
Sure, fission-waste is not something you want. But it sure beats the crap out of coal.
Something wrong with nuclear power? Oh yeah... (Score:1, Insightful)
Oh yeah. It is extremely expensive and dangerous, and the waste is so nasty that no-one has found a safe way to get rid of it yet. Cool down, Mr. Burns.
"Sure, fission-waste is not something you want. But it sure beats the crap out of coal."
Really now? OK. You have a choice. A bucket of fission waste under your bed, or a bucket of coal. Which one do you choose?
Re:Something wrong with nuclear power? Oh yeah... (Score:5, Insightful)
If I am not mistaking, nuclear power is the cheapest.
A bucket of fission waste under your bed, or a bucket of coal.
Don't compare these things. The first is a waste product, the second is the raw material.
The choice should be between a bucket of fission waste and a room filled the ashes and gasses that resulted from burning coal. I am not sure what would kill you first.
I don't want either of them. But the fission waste can be stored and handeld. I a century or so, we might find a solution for it. The gas on the other hand goes in the atmosphere. You try getting it out. It too might be possible in a century. At least with fission waste the poles don't melt and the climate doesn't change. Although I do have to say that the sun is also partially responsible for a temp-rise.
I don't understand the problem people have with fission. Sure it aint pretty, but it's the best we have so far.
Re:Something wrong with nuclear power? Oh yeah... (Score:5, Informative)
Anyway, this is a discussion on solar cells, which lend themselves to distributed power generation of some form or another - they don't have to be big. More efficiency there makes the solar powered laptop easier to acheive.
Re:Something wrong with nuclear power? Oh yeah... (Score:2)
Yes, that was I meant. But if it takes you a week to die from radiation poisoning, but only a day to die from lack of oxygen. Then the coal killed you. But for all I know it could be the other way around.
More efficiency there makes the solar powered laptop easier to acheive.
Yes, I was wondering why I haven't seen that yet. Except in some film. Then again I didn't know solar cells were that inefficient.
Re:Something wrong with nuclear power? Oh yeah... (Score:3, Insightful)
You were aware that coal ash is highly toxic as well as radioactive, weren't you? With direct exposure to nuclear waste, you could die from radiation sickness (needing something like >10,000 rems to do that) or get cancer somewhere down the road. With direct exposure to coal ash, you could get poisoned by toxins, die from cancer somewhere down the road from that exposure, or die from cancer from the outputs of that power plant in the
Damn, forgot my coal info link (Score:2)
Re:Damn, forgot my coal info link (Score:2)
Re:Damn, forgot my coal info link (Score:2)
From the article: "Coal ash is composed primarily of oxides of silicon, aluminum, iron, calcium, magnesium, titanium, sodium, potassium, arsenic, mercury, and sulfur plus small quantities of uranium and thorium. Fly ash is primarily composed of non-combustible silicon compounds (glass) melted during combustion. Tiny glass spheres form the bulk of the fly ash."
If anything is tin foil, it was
Re:Something wrong with nuclear power? Oh yeah... (Score:2)
No I'm not - knowing some basic chemisty I know what highly toxic actually means, and knowing a bit about the ash recovery process i can tell you that ash is mostly silica. Ash is removed from the bottom of the boilers, and also from the flue gasses (the final stage is electrostatic precipitation to get all of the light material). The ash is handled wet and pumped into an ash dam, where the heavy material sinks. The light ma
Re:Something wrong with nuclear power? Oh yeah... (Score:2)
"Coal ash is composed primarily of oxides of silicon, aluminum, iron, calcium, magnesium, titanium, sodium, potassium, arsenic, mercury, and sulfur plus small quantities of uranium and thorium. Fly ash is primarily composed of non-combustible silicon compounds (glass) melted during combustion. Tiny glass spheres form the bulk of the fly ash.
"Since the 1960s particulate precipitators have been used by U.S. coal-fired power plants to retain significant amounts of fly
Re:Something wrong with nuclear power? Oh yeah... (Score:2)
The article forgot to mention all of the other elements in the earths crust but that is the way it is going. Coal ash is mostly silica, with the other constituants in small amounts varying depending on where the coal comes from. I suggest you look it up in a reputable source. What you quoted is not a reputable source - cenospheres may be silica but they certainly are not
Re:Something wrong with nuclear power? Oh yeah... (Score:1)
Not entirely true! There was a steam explosion
After the chain reaction in the reactor went out of control, the cooling system overheated and finaly exploded. This first stem explosion lifted of the cover plate of the reactor, but released only some fission products to the atmosphere. After the first (steam) explosio
Re:Something wrong with nuclear power? Oh yeah... (Score:2)
Fair enough. But let's be completely fair. We've had over a hundred years to refine coal power production. Nuclear power has come into its own much faster than coal. You say that nuclear is an expensive way to boil water. Fine. Light water reactors can only get 3-6% of the actinide-based material to fission. Light water r
Re:Something wrong with nuclear power? Oh yeah... (Score:1)
"No I didn't, and I suspect the only people who do know have read some pamphlet on behalf of the nuclear industry. It sounds very unlikely to me - where is it all going to come from? "
I am not sure, if the grand parent is right, regarding radiation around coal power plants. However the point that coal power plants produce highly radioaktive waste is correct.
The e
Re:Something wrong with nuclear power? Oh yeah... (Score:2)
No, it isn't.
Highly radioactive waste by definition is material which emits particles in large numbers- ie shows evidence of radioactivity. It can be easily shown whether something does or doesn't fall into that catagory. That small amount of radioactive material that you will find in a few hundred tonnes of coal when concentrated twenty times (assuming 5% ash) still doesn't add up to much at all. It's certainly less
Re:Something wrong with nuclear power? Oh yeah... (Score:1)
Hm
Reliability and cost efficency was proven on 25.4.1886 in Chernobyl.
Ok, this is a bit trolling, however the extend of the damages caused by accidents with nuclear
Re:Something wrong with nuclear power? Oh yeah... (Score:1)
The problem with fision has a name... (Score:1, Insightful)
Re:Something wrong with nuclear power? Oh yeah... (Score:2, Informative)
And if you wait a century, you don't have much beyond cold metallic waste. At one point the anti nuclear folk thought they'd stop the plants by refusing any
Re:Something wrong with nuclear power? Oh yeah... (Score:1)
Oh god, not another "greenhouse effect" true believer. Show me some real evidence that the amount of extra CO2 we humans produce has any real effect on our atmosphere. What I find even more ludicrous about these near religious beliefs is that we all admit that fossil fuels are limited. Even if the CO2 we produce is enough to produce those kinds of global climatic changes, we will have consumed all of our fossil fuels (or at le
Re:Something wrong with nuclear power? Oh yeah... (Score:1, Offtopic)
As for the choice of a bucket of
Re:No Solar For You! (Score:3, Insightful)
Re:No Solar For You! (Score:1)
Mining equip is often electric (Score:2)
Underground equipment tends to be even more electrified. Here is a photo of a chairlift, [mining.ubc.ca] yes- like the skiing kind, being used in an underground gold mine in Africa.
-AD
Re:No Solar For You! (Score:2)
Something wrong with nuclear power?
Face it, dude. We're fucked. We're fucked in a big way. I don't mean to sound overly pessimistic or anything, but real like completely fucked. Our power infrastructure is goatse.
Here's the problem. Let's say oil is peaking right now, as Bush's energy advisor has said. So oil production drops, demand continues to grow, and so forth. Let's say the whole process to reach economic bankruptcy when oil becomes too expensive takes, oh, 30 years. Let's just say.
How lo
Re:No Solar For You! (Score:1)
Re:No Solar For You! (Score:2)
Re:No Solar For You! (Score:1)
So, solution to world's oil problem: Find a better
way of getting the oil that is there out. There's
plenty left.
Re:No Solar For You! (Score:2)
Tertiary recovery of oil (Score:3, Informative)
You can get around this by using a non-polar solvent instead of water. Liquid carbon dioxide is good for this, with two further benefits:
Re:No Solar For You! (Score:1, Insightful)
Don't underestimate their ego.
Solar energy . . . the big picture . . . (Score:5, Interesting)
One things that I've never seen is the lifetime and disposal costs of solar cells . . . that never seems to be factored into the so called "solar renewable energy" equation.
Re:Solar energy . . . the big picture . . . (Score:5, Informative)
The ROI (for retail and manufacture cost) and the Enviromental impact of production is addressed.
Granted the source is an RE magazine, but they do list references on some of the studies if you want to follow up.
Re:Solar energy . . . A grain of salt (Score:1)
Tanstaafl
Re:Solar energy . . . the big picture . . . (Score:4, Interesting)
I find it odd that the first page says "Myth: Solar living means sacrificing conveniences," while later on it says, "A PV system provides the required electricity. This type of design is not the norm by far--it's just a little too expensive
up front for most people--and it might require the owners to put on a sweater indoors a few times a year." Turning up the heat when you're cold is a convenience. Having to put sweaters on, however simple and beneficial a solution it may be, is NOT a convenience. Hint: If you are forced to seek an alternative, it is not as convenient.
When it's sunny, yes, you can use it in northern latitudes. What happens during the rainy season? In many northern states, the rainy season is at least half the year. Go on battery the whole time the sun isn't visible? What happens if (when!) the battery goes dead? Americans used
And let's discuss cost. The brochure you presented states that costs are so bad. Last I checked, good solar panels for the home were upwards of $30,000. If you are already paying for a new house, the extra cost of setting up solar is marginal. For folks who are just getting by (everyone with kids in college), $30,000 just isn't there. Costs from environmental damage where we don't immediately see the price tag? That's fair. Absolutely that's a fair statement to make. Then again so is saying, "What about the hidden costs of completely ripping out an established infrastructure in favor of a new one?" Isn't that fair too?
Once again, a fair statement. However how is microhydro going to handle the macro scale when you (a) can't pack them closely together and (b) cannot disrupt the normal activity of the surrounding water? Put more in to get more energy? Remember the 1st Law of Thermodynamics. As it is not created nor destroyed, if you use a sufficient amount of energy in one system, that amount is removed from another system. Environmentally sound? Reducing the energy by a significant amount would be environmentally sound? Most of the world's creatures live at or near a coastline. Carefully consider whether or not you want to mess with this substantially.
This one kills me. First of all, the term "nukes" usually refers to "nuclear weapons." The requirements for nuclear power are dramatically different from those of bombs. You might as well assert that electricity should be banned because electric chairs are made. It has no place in a power generation conversation. Second of all, there are nuclear reactors such as IFR (Integral Fast Reactor) [anl.gov] which were designed specifically to address critics' problems with nuclear. It does not rely on coolant, computer control, or human interaction/intervention to prevent accidents; Safety is dependant upon natural phenomena and the laws of physics to operate. The working prototype for IFR [anl.gov] conducted a series of tests where coolant was shut off and all of the usual precursors to a meltdown were put into place. No damage. No leakage. Nothing but a safe, controlled shutdown -- without human or computer interaction. This is not hypothetical. This is historical fact. In fact,
Re:Solar energy . . . the big picture . . . (Score:1)
My problem is that most people seem to think that solar panels are trash because they are not anywhere near 100% effecient. Even at today's standards most panels will return their manufacturing energy investment and a users financial investment well before the end of their life.
In the right application, they are extremely useful. Running a remote
Re:Solar energy . . . the big picture . . . (Score:2)
I am however utterly convinced that coal, oil, and natural gas should not be energy sources we fall back upon. (Note: 51% of today's power generation is from coal.)
My only other comment on this is that switching infrastructures -- such as widespread adoption of home solar panels -- will not be a qu
Solar power daylight calculations (Score:2)
You already took daytime into account with the 8-hour figure.
Accounting for clouds and rain would probably reduce the daily sunlight average low enough that energy needs wouldn't be met.
An effective way to use renewable energy exclusively is to build huge solar ar
Re:Solar power daylight calculations (Score:2)
Thanks for the correction. In truth, I was spending some time on that comment (that very few will probably ever read). In the editing/revision process, that ended up as an unwanted artifact from an earlier draft.
Re: Don't launch solar panels into space (Score:2)
What would be launched into space would be factories that would capture asteroids and build solar panels out of them.
So we don't have to "get the huge solar arrays into space", because we build them out of material (asteroids, comets, etc.) that is already there.
What has to be launched are the factories.
Or go one step further: launch one or two factories into space that use an asteroid/comet to make many solar panel fa
Distributon grid costs will obsolete remote power (Score:2)
Re:Solar energy . . . the big picture . . . (Score:2)
Exactly how old is the Niagra Falls plant? Hydro is a tried and true technology refined over a century. Scaling down is a lot harder than scaling up.
I suspect that is a major reason there are none of these plants operating. You may recall that the only plants built over more than the last decade h
Re:Solar energy . . . the big picture . . . (Score:2)
But I guess you're right. We should set up hydroelectric at every major waterfall. Where were they in Idaho again? I've forgotten exactly.
Re:Solar energy . . . the big picture . . . (Score:5, Informative)
There are some nasty chemicals required for production. The total environmental impact, however, is significantly smaller than obtaining the same lifetime amount of power from any other source available. The waste produced by a similar amount of power from coal, nuclear, gas, etc... over a similar lifetime is significantly larger.
The pollution only happens once, for 20-30 years worth of power. The pollution from any other option doesn't stop unless you stop using it.
Re:Solar energy . . . the big picture . . . (Score:2)
Re:Solar energy . . . the big picture . . . (Score:1)
You need to check the facts more (Score:2)
Typical efficiency of silicon solar cells is 15% or so, and if I recall correctly the Luz concentrating solar plants were able to beat 20% (I could be wrong, a search did not turn up any solid information).
But that doesn't matter. There is no shortage of sunlight; the problem is the expense of collecting it. This makes the most important metric $/W instead of W/m^2, and cutting $/W is the worthiest goal for the widest va
Re:Solar energy . . . the big picture . . . (Score:2, Insightful)
Which accounts for about half the cost of buying and installing said panels. So you can expect them to pay for themselves in about 8 years - except by then you'll need a new set of batteries. So ~10 years until it starts earning you money.
In fact I think swapping batteries at least 4 times in 30 years will provide a more significant form of p
Don't use batteries. (Score:2)
Nonetheless, I wouldn't suggest to most people that they try this to save money. It's at the point where you can break even in 8-10 years, but that's still the sort of time frame where it appeals mostly to folks who are doing it because they want to, not because it's a financial ga
Re:Solar energy . . . the big picture . . . (Score:2)
Re:Solar energy . . . the big picture . . . (Score:1)
Re:The real question is ... (Score:1, Funny)
The only equation that matters (Score:4, Insightful)
When it comes to adoption of solar power, there's only one calculation that really matters:
C = Cost of installing solar panel
R = Revenue generated (or money saved) per year
M = Maintainence costs per year
(R - M) >= C * 20%
In plain english, when you can get (somewhere around) a 20% return on investment from installing a solar panel, you'll start to see them on top of office building, parking garages, and just out in the middle of open fields, soaking up money.
Until then, solar power will be a technical curiosity for use in special situations (outer space) and for those with a political agenda.
Re:The Socialist solution (Score:3, Insightful)
So under Socialism there is *no* incentive to use them other than political adgendas.
=Smidge=
Re:The only equation that matters (Score:3, Interesting)
Re:The only equation that matters (Score:4, Insightful)
There's also other factor encouraging the use of solar cells. For one, they're much more durable. There's some cells now that can be used rdirectly as roofing tiles where you can put nails through them and walk on them. They aren't the best panels out there but the ruggedness factor is attractive. Also, most power companies now let you sell off excess capacity back to the power grid these days. That development alone can make solar cell arrays in sunny areas pay for themselves in 10 years or so.
Unfortunately, I live in Seattle, land of little direct sunlight and no steady wind. Renewable energy for me is out until those solar cells get another 50% decline in $/kWh.
Re:The only equation that matters (Score:1)
Hmmmm..... hold the phone...
Re:The only equation that matters (Score:1)
Re:The only equation that matters (Score:2)
I suspect that once solar power gets to the point where it can pay for itself in under a year, you'll see public attention start hitting it. I am encouraged by those little solar powered lawn lgihts, though. As cheesy as they are, they are popular and start to subconciously affect people to think that 'Hey, solar power *do
Re:The only equation that matters (Score:1, Insightful)
If I could get buy an investment that would give me a tax free return of 7% I'd leap at it. I say tax free because saving money isn't taxed. A penny saved is more than a penny earned because a penny earned is taxed.
We did the time warp again? (Score:4, Insightful)
In plain english, there are other design criteria other than a very simple equation even an economist could understand. Economies of scale mean that in most cases it is cheaper for a business to get power from a grid, no matter what powers it.
Re:We did the time warp again? (Score:2)
Uh hunh... Please read my comment [slashdot.org] from another thread. Solar doesn't scale. It runs up against the 1st Law of Themodynamics. A calculator is not the same as serving all of our country's energy needs.
Re:The only equation that matters (Score:2)
(cost of solar) (cost of grid power).
The cost of grid power has seen a steady increase of about 6%/year, and the cost of solar is coming down. With net metering and time-of-use metering (i.e. you sell your electricity to the power company), a residential solar system can start paying for itself on day 1.
Great news (Score:3, Funny)
This underscores the need for ... (Score:3, Interesting)
Re:This underscores the need for ... (Score:2)
Whatever happened to the idea of superconducting power rings? Did the magnetic flux intensity just prove too g
Re:This underscores the need for ... (Score:2)
I have not seen anything on that in a long time. Last I heard of superconductors were still below liquid nitrogen temps, therefor requireing liquid helium/hydrogen (both too expensive). But that is certainly why a funding for storage needs to take place. Interestingly enough, I was thinking that this could even help nuke plants. They are always hot and capable of 24/7 production. So this can increase the output by quite a bit. Cheap way to increa
Re:This underscores the need for ... (Score:2)
Re:This underscores the need for ... (Score:2)
The main problem with superconducting storage is that high-temperature superconductors break down at relatively modest [for power storage] field strengths (in the range of 1 Tesla), and liquid helium cooled superconductors are only somewhat better (best I've heard is 8 Tesla for particle accelerator magnets cooled to 1.8K).
It turns out that the situation is even worse, thou
Re:This underscores the need for ... (Score:2)
Cheap spray-on coating that generates electricity! (Score:3)
The bad news is that shortly thereafter, everything will turn an odious dull black.
Other development (Score:4, Informative)
Re:Other development (Score:2)
[...]
manufacturing panels 400mm x 500mm @ 20W
That says they're speccing them to about 10% efficiency.
Try Low-Tech First (Score:3, Insightful)