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Breakthrough in solar photovoltaics
An anonymous reader writes "The Holy Grail of researchers in the field of solar photovoltaic (SPV) electricity is to generate it at a lower cost than that of grid electricity. The goal now seems to be within reach.
A Palo Alto (California ) start-up, named Nanosolar Inc., founded in 2002, claims that it has developed a commercial scale technology that can deliver solar electricity at 5 cents per kilowatt-hour. " As always, take these claims with a dose of salt the size of the Hope Diamond.
It varies between 3 and about 6 KW per sq. M
Jeroen
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From what I read on the website: nanostructured materials, estimated lifetime of 25 years, made of "nontoxic semiconductor paint" suggests that it is about dye-sensitized solar cells. These are based on small TiO2 particles, the same that is used as a pigment in white paint. These do not absorb visible light by themselves, but can catch and transport electrons from certain light-absorbing dyes. These solar cells were invented around 15 years ago; the necessary components of such a solar cell, TiO2, dye, solvents, sandwiched between two glass plates, are relatively cheap, but the yield is still below 10% (sunlight power to electrical power).
Apparently, this company has found a way to mass-produce cells based on this principle using plastic films instead of glass. The glass was the most expensive component; the problem with plastic films is that it is hard to make them last a long time while still being impermeable to oxygen and the liquid solvent inside the cell.
Avantslash: low-bandwidth mobile slashdot.
Their management team looks top-notch (ex-Intel, NIST, etc.); their partners include Sandia, Stanford, and Berkeley; and their investors include Stanford and Sergey Brin and Larry Page.
I think these guys are for real.
I claim first use of "Error No. 0B" - or "No. 0B error." It'll be the new ID 10T!
this implies that the sheet 10 X14 feet produces around 1.5 killowatts, and costs around 500 bucks!!!!! GIMME GIMME I WANT ONE
watch "the money masters" on google video
Q: What is the expected cost per square meter of typical Nanosolar solar cell module?
A: A square meter of (an array of interconnected) Silicon solar cells (a "module") has a product cost of approximately $300 (or $2.75/Wp) from today's cost leaders in Silicon. Nanosolar solar sheets/modules are based on much thinner cells (up to 1000x thinner in their active layer) and tend to cost as little as $30 per square meter, or 10x less. Note that this does not mean that there is a cost/performance difference by this same factor, however, as Silicon solar cells will continue to be the efficiency leaders for the forseeable future.
According to this (and several other sites), it's about 1.4 kW/m^2 (at 1 AU, perpendicular to direction of Sun, in space). This is 0.9W/sq. in. or 130W/sq. ft.
So the article has got something badly wrong...either they've got the units wrong - 120W/m^2 sounds plausible, 120W/sq. ft. is theoretically possible but extremely unlikely as it would require 90% efficiency, 120W/sq. in. is totally impossible for Earth based solar - or they're being taken for a ride.
http://www.nanosolar.com/pr2.htm
Well, it said 12% efficiency, so I'd assume they meant per square *meter*, since 120 W/sq m corresponds to 12% efficiency.
120 Watts per square inch would rock, though -- it's about 200 times the theoretical maximum.
Kill, Tux, kill!
6 kilowatts per square meter? That's a 'you must be on crack' figure.
Here are some actual numbers:
Note that that's *peak*. Averaged over, say, a year, which includes periods where the sun doesn't shine at all ("night"), as well as periods where it's not high noon on a cloudless day, and average insolation falls quite a bit. This site claims a yearly average for central Australia of 5.89 kilowatt-hours per meter per day, which (if my conversion is right), breaks down to an *average* insolation of 245 watts. So just flat-out double that to get rid of the night time, and you're getting an average value of about 500 watts in one of the sunniest, hottest places on the planet.
OK, since this is a solar photovoltaics post:
Someone is going to claim that solar will never be practical, because it is 10 - 15% efficient, while internal combustion, etc. is 30%+. Please, consider that you have to *buy the energy* that goes into that 30% efficienct machine, while the 15% efficient solar panel gets it all free - then run the numbers. The only cost that matters is the dollars per Watt capital cost of the cells upfront (which is still too high, but coming down.)
Someone is going to claim that solar panels produce less energy over their lives than it takes to manufacture them. This has not been true for about 40 years.
Someone is going to claim that solar panels are a toxic danger to human health. Please consider that they are manufactured using identical processes to microprocessors, are easier to disassemble for recycling, and last 20 - 30 years plus, as compared to the five year or so length for most consumer electronics.
Someone is going to claim that solar only makes sense in certain parts of the United States. Keep in mind that, for instance, Albany, NY gets 80% of the solar radiation of Reno, NV. Since you pay twice as much for electricity in Albany, solar panels actually make more sense there. (Remember, most solar panels go on rooftops and spin meters backwards - you get retail price ($.08 - $.15 / kWh,) not wholesale ($.02-$.04) like a power plant.
Someone is going to claim you would have to blanket the desert with solar panels to make a workable power plant. Is this what you do with a distributed, smart, resource, that can occupy unused roof space anywhere? Did we take all of our microchips and assemble them into one giant supercomputer in the desert? Solar panels belong in a distributed network of generators - at the end of the wire, and putting them there is cheap and practical.
Someone is going to claim the solar industry can never meet real-world power demands. Check any industry publication for an interesting statistic - in 1996, 100 megawatts of solar were manufactured. Jan - Dec. 2004 saw about 1100 MW (about $ 6 billion worth) manufactured. Still pretty small, but an amazing growth rate.
What does solar cost now? About 1/20 what it did in the 1970s, but still about twice as much as grid electricity. Once you buy the panels, and finance them with, say, a home equity loan, you're looking at $.18 - $.25 /kWh. Getting closer every year, but still not quite there.
Finally, a comment on the article. Yeah, Nanosolar is pretty neat, but I think that Konarka is quite a bit further along - and doesn't share nanosolar's tendency to overpromise. Here's what needs to happen. Their efficiency is fine, don't care - a 5% or 10% efficient cell, as long as it's less than $1.50 / Watt, the world will beat a path to your door. However, their longevity is not there. A normal silicon solar panel lasts at least 20 years, these things last more like 5 right now. Hence their strategy of putting them in consumer electronics that have about that lifetime anyway.To be a real power generation source, they need to get that lifetime up by a factor of 4 - doable with the right encapsulants, some chemistry, getting rid of liquid electrolytes, etc. I bet one of these poeple will be at $.10 / kWh in five years - but the conventional silicon cells can probably get there in about 8, with manufacturing and scale improvements. So it's a real race...we'll see who pulls it out.
First, by "manufactured by printing", they don't mean a roll to roll process like a printing press. They propose to deposit materials with an inkjet-like mechanism.
Second, what they call "nanotechnology" is surface chemistry. There are ways to make semi-regular structures by bulk chemical means, and that's what they're doing. They did throw a reference to "bioengineered self-assembly" in, but that's not how they do it. The processing looks much more like processes you'd do in a wafer fab. There are common fab processes like electrodeposition, chemical removal of support substrates, and heating in an inert atmosphere.
The basic idea is to address the reasons that solar cells are inefficient. In bulk materials like silicon, only a small fraction of the photons do anything useful. Most of the photons are at the wrong wavelength. And many of the photon interactions that do occur don't result in an electron being delivered to the output. They're trying to fix both of those problems.
Their policy seems to be to shut up until it works. It might work, or it might not. They're not selling stock, and they're not issuing press releases. They have VC funding and some money from DARPA.
Most peole believe that the grain of salt is the antidote to the mistruth. The true meaning is lost in the mists of time so you might be right or they might be.
According to Word detective:
> Actually, it's just the reverse, thanks to Enron and California's refusal to build new power plants.
California did not refuse to build new power plants, and has in fact been building them like mad ever since it got raped by Enron.
Enron shut down Enron's power plants, Enron moved out of state, became a distributor only, and Enron did so deliberately in order to create shortages. Enron managed to pin this on CA, and to this day, Enron's criminal behavior has gone unpunished by regulators while California seeks to get back the overcharges caused by Enron.
Clear?
My girlfriend lives in a solar powered house here in BC (Canada). For 4 months she has to suplement power from the grid, but for the rest of the year, it's enough. That's big savings. Another friend lives in a passive solar house, and only had to fire up his heat for about 2 weeks this winter. And these are spacious houses with lots of windows and all the normal (power saving) appliances.
The thing about these techniques is; they're cost efective _now_, if you can aford the capital outlay. Your bills go down, and it pays for itself.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
They don't have the problems of past low power bulbs. They don't blink. I've never noticed a blink rate, and I've been reading by them for 4 years. They do take 20-45seconds to get to full output. A 60-watt rated bulb (actually 15 or so watts) starts out at what I would say is 40-watt equivalent light, but it gets up to full in less than a minute. That's great, if you need more than 40W incandescent-equivalent light, you're going to have the light on for more than 20 seconds, so don't anyone think about complaining about that.
Everyone that hears me should go out and buy these for their homes. I don't mean to sound demanding. I sincerely desire to know what would be a good reason not to use them, because I can't find one.
These bulbs are sold as long-lasting, or cost-saving, but they need to instead be sold as environmentally friendly, and as using 75% less fossil feuls while their on, 75% less CO2 created, etc, etc.
KLAATU, BORADA, NIh*ahem*
A detailed plan for generating electricity in the Sahara already exists. The technology is called Concentrating Solar Power or CSP and has already proved itself on a large scale in the Mojave Desert. The details have been worked out by TREC, the Trans-Mediterranean Energy Cooperation. See http://www.trec-eumena.org/
The results of the EU ECOSTAR CSP program have just been released at a workshop held last thursday in Brussels. The 140-page report can be downloaded from ftp://ftp.dlr.de/ecostar. CSP power stations occupying an area the size of France in the Sahara, using available technology, can produce the current total energy consumption of the whole world.
Any study which shows that solar cells take more energy to produce than they make in their lifetime must have been written in the 1960's because solar cells have been net efficient for a LONG time. The problem has been that they weren't COST efficient. With rising fuel prices and increased efficiency we have known for some time that the balance would tip in favor of solar. The problem is that solar has to be significantly CHEAPER than the utilities on a per unit basis because you have to make back both the cost of electricity AND the oportunity cost on capital. Btw central NJ is barely cold in the dead of winter, try Northern Ohio, Minnesota, or parts of Canada for cold. I'm not saying passive solar heating is bad, it's very good, but it won't supply enough BTU's for heating even a moderate sized home in colder climates.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
First off, despite what Enron did, the State of California dug itself into a hole because of NIMBY. There was little or no plant construction in California during the 1990s, a time when the population boomed. It was impossible to get permits for new plants and most new construction was tied up in courts over environmental issues. When the crunch did happen, Enron and others wrongly exploited California, but not at all in the way that has been oversimplified by the press or even the idiot Ralph Nader types.
California, because it had not built enough power plants, was importing power from other states.
In order to import power you have to have your own power system suitably balanced. It's not like you put electrons on trucks and wheel them in. To do this, you offer financial incentives to buy or sell power at various points on the grid. To this day, PJM does this on the east coast and you can actually check it out here PJM LMP pricing
Also, you have to adequate transmission rights to get the power in.
So what Enron did was rather clever. First, they had better software than the California ISO for determining grid imbalances and so they scheduled power deals to manipulate the grid. Import power in the north, export it in the south, boom there is an imbalance, and you can sell the power you exported back to the state for a lot of dough. Then, they would also go and buy up transmission rights into the state (which is actually pretty cheap), and then play games at peak times.
The amazing thing about the whole thing is that gaming California's stupid grid managers WAS LEGAL. That's right. Enron didn't do -anything- wrong by screwing the state of California. The state made its rules for its market place and Enron exploited them, but California should not have made those rules to begin with. To cap it all off, California deregulation stripped utilities of the ability to pass variable costs to consumers. So, if the price of electricity shot up, it should have shot up for consumers as well, and guess what, people turn their air conditioners down, and there is no power crisis. But oh no, California made it so that the utilities could not recover the costs and so they had to sell power at a loss, and all the utilities in California went bankrupt, and Enron made a mountain of money, legally.
The thing that got Enron into trouble was that they were lying on their financial statements, and for that, the company is now bankrupt, her executives are either on trial, and the accounting firm that certified those statements no longer exists.
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