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Bigger, Cheaper Solar Cells
Phenombecile800 writes "First Solar, a start-up from Arizona, is making photovoltaic cells at a fraction of the usual cost. Their secret: increasing the light-catching area 'from postage-stamp to traffic-sign dimensions,' reducing the manufacturing time to 1/10th of the competition's, and thinning the active element to 1/100th the usual thickness over a glass substrate, which enables the production of large panels. IEEE Spectrum provides some technical details about the production process. 'Glass is placed on rollers and fed into the first chamber, where it is heated to 600 C. Then it is transferred into the second chamber, which is full of cadmium sulfide vapor, formed by heating solid CdS to 700 C. The vapor forms a submicrometer deposit on the glass as it moves through this cloud, after which a similar process in a third chamber adds a layer of micrometers-thick CdTe in about 40 seconds. Then a gust of nitrogen gas rapidly cools the panels to 300 C in a fourth chamber, strengthening the material so that it can withstand hail and high winds.'"
The story doesn't say larger is better per se. The story says that these cells are cheaper because they can be manufactured on a different scale. The most efficient solar cells are unfortunately only in labs at the moment and may not make it to consumers because of cost. Such it is with a lot of technology. The efficiency/cost ratio is important for more widespread adoption of solar technology.
Well, there's spam egg sausage and spam, that's not got much spam in it.
Cadmium Telluride is also a direct bandgap semiconductor which yields more watts per kg than the indirect bandgap semiconductor materials. Solar cells become less efficient at converting solar energy into electricity as their temperatures increase but Cadmium Telluride is less susceptible to cell temperature increases than traditional semiconductors generating relatively more electricity under high ambient temperatures. It's also more efficent at converting low and diffuse light to electricity more efficiently than conventional cells under cloudy weather and dawn and dusk conditions.
They also have a recycling plan in place for the lifetime of the product - somewhat at odds with the traditional landfill methods of yore. But, no retail. They don't sell to individuals and only deal with utility companies. Finance trivia: Their stock has grown spectacularly since the IPO and there is a large investment from the Walton family (insert TV joke here)
Physics is like sex: sure, it may give some practical results, but that's not why we do it.
$3-$4 per watt. Slightly better than 10 percent efficiency. There, I just saved you two boob-less hours.
You have the right to your stuff--if you're willing to pay out the ass for it. That's what it's coming to, you know. NYC nearly implemented congestion pricing like London already has. That means you would have had to pay $11.00 just to enter Lower Manhattan. Owning a car is not going to get cheaper. Let the market convince you that you don't need your stuff. That's the American way.
The head of Applied Materials solar division said in a talk at Stanford last year that their solar panels took two years of their own output in energy to make. They hope to get the energy breakeven point down to six months. He said the sputtering process they use in coating is energy-inefficient, and they're trying to develop something better.
Total installed energy cost is probably higher. Home solar installations are about 50% installation cost. The big open-field installations are cheaper; they have economies of scale.
Forbes mentions that Mojave Desert real estate is becoming more valuable because many companies want to build solar facilities there. There's plenty of space in California, Nevada, and Arizona for solar panels.
Mike Splinter of Applied Materials (the largest maker of semiconductor fab gear) likes to say "Everybody else's costs (in the energy business) are going up, and ours are going down. We're nowhere near market saturation. This is a great business for us."
What everyone seems to be waiting for is a cost-per-watt that is low enough so that ordinary people will decide to start buying them in large quantities without government subsidization.
You won't see it from FSLR, unfortunately. Their output is currently (no pun intended) earmarked for commercial ventures only, no retail/residential sales. Pity. Hope that changes.
Mit der Dummheit kämpfen Götter selbst vergebens.
Article gives the size of the glass, and some temps, so it may just be answerable. Googling for: how much energy does it take to manufacture glass, 5 hit (no direct link since its a f***in word doc)
The Recipe For 1 Ton Of Glass (Resources)
1300 Pounds Sand
400 Pound Soda Ash
400 Pounds Limestone
150 Pounds Feldspar
24000 Gallons Water
4400 KWH of Energy
So, 4400 KWH per ton.
How much do the panels weigh?
(.6 m) * (1.1 m) * (.5 cm) * (2 500 (kg / (m^3))) = 8.25 kilograms
(8.25 kilograms) * 4 400 (KWh / ton) = 144 Mj
Apart from making the glass, there is heating the glass, heating the cadmium sulfur and telluride, mining all those chemicals, etc.
Glass specific heat is .84 J/g K.
(.84 (J / g)) * 8.25 kg * 580 = 4 019 400 joules
So I've calculated 148Mj for the glass manufacture and heating.
Ignoring the cadmium, sulpher, telluride chemical mining, what do you get out of it?
(85 watts) * 25 years = 6.7 Ã-- 10^10 joules
How much coal is that? http://www.newton.dep.anl.gov/askasci/eng99/eng99187.htm
6.7E10 joules) / (4.11E6 (joules / pound)) = 7 400 kg
Remember how I ignored the energy of mining those chemicals?
How does the energy compare for mining the GRAMS it would take to deposit a film of telluride compares to the energy for mining TONS of coal.
The answer to what you did ask, at least for the glass + heating, is pretty easy to answer:
(148E6 / 85) * s = 480 hours. Less than a month.
Cadmium is nasty stuff. The primary human exposure to cadmium is cigarette smoke. Not so much from industrial uses such as batteries, pigments etc.
There is some history of cadmium in run off water from mines causing cadmium poisoning in Japan. Cadmium poisoning is known and ouch-ouch disease. It is so painful that people don't die from it, they commit suicide first.
Not based on this new technology, but here's the info:
From http://www.nrel.gov/pv/pv_manufacturing/cost_capacity.html
National Renewable Energy Laboratory
Photovoltaic Research - PV Manufacturing R&D
Cost/Capacity Analysis
The PV Manufacturing R&D Project Coordination Team measures and tracks the progress of the Project's impact on module cost and production capacity. The module-manufacturing partners voluntarily provide the team with two types of critical information: direct costs of module manufacturing and manufacturing capacity. The direct costs are those costs directly associated with module production and do not include such costs as research, sales/marketing, or general administrative expenses.
Direct costs of module manufacturing dropped from $5.89 per peak watt in 1992 to $2.73 per peak watt in 2005 dollars. These results represent a total cost reduction of about 54%, or an average annual drop in direct cost of about 5.5 percent. In addition to supplying the most recent year's data, these partners supply their projections for the coming 5 years.
The cost/capacity graph below shows the 2005 data of 14 Project participants with active module manufacturing lines in 2005. A participant in this case refers to a subcontractor with a manufacturing line. The graph shows continued progress toward meeting the Project goals of decreasing direct costs of manufacturing and increasing production capacity.
PV Industry Cost/Capacity (DOE/US Industry Partnership)
The production capacity shown is the total capacity of the 14 participants. It represents the potential production if all the plants were running at full capacity. Through 2005, the graph shows that total module production capacity grew from 14 MW at the start of PVMaT subcontracts in 1992 to 251 MW at the close of 2005. These results represent a 19-fold increase or about 26% average annual growth in production capacity among these Project participants.
From the perspective of technology learning curves, these data reflect an average 17% drop in direct costs of manufacturing for every doubling of production capacity.
-- Boycott Shell
I've read somewhere that cadmium is a byproduct of zinc refining/smelting, tellurium instead seems pretty rare (according to Wikipedia)...
A couple of things to keep in mind here:
Find free books.
Suppose you're having a new house built: if you could install a ten or fifteen kilowatt solar plant and inverter for ten grand, you might figure it's worth it to borrow a little more money from the bank.
More and more mortgage companies are financing solar energy systems. Some allow borrowers to borrow more because of such systems. With an alternative energy system installed living costs are reduced so they are willing to lend a higher percent of the what the borrower's income would suggest.
Of course the mortgage crisis does have a negative impact, it has hurt solar businesses.
Falcon
Should there be a Law?
An off-grid solar + wind system can easily cost $60,000, but if, like us, you live in a rural area it could quite literally be a life saver. Spending $60,000 with no idea how it would affect your costs would be like gambling all your money away on the stock market.
You need to budget for long-term maintenance. And to do that you need to know about reliability of the equipment, and about how long before it's paid for itself, to work out the average costs including replacement parts.
Live barefoot!
free engravings/woodcuts
Glass production lines don't "start up in the morning". They run 24x7, because of the huge amount of thermal energy in the system. If they cool down, it's a big deal. Everything solidifies and likely can't get started again. It's the equivalent of warming up a superconducting magnet. Float glass production lines are built for a particular lifetime. When that's up, they allow it to cool and trash the whole plant.
Making mad money can also encourage others to get into the industry.
The solar cell industry is already incredibly bloated and does not even obey real economic rules due to high subsidies.
My dispute with this line of reasoning is that we use an insignificant amount of oil for electricity generation purposes. So your three war argument is off-topic.
The significant hydrocarbon sources for our electricity is coal and natural gas.
Of which, receive some of the most marginal amounts of subsidy in the industry
As for being used on cars and such - solar doesn't have enough density to realistically power a car via an on-car array.
I don't read AC A human right
If your thinking Obama is going to do anything to hurt big oil your going to be very surprised. Sure he may hurt some of the smaller American players, but never the big players in Muslim countries. Bush was in the pocket of big energy companies, Obama is in the pocket of big Oil companies.
More likely these installations will use the good old Nickel-Iron battery
In many respects the Nickel/Iron battery was almost "too good." A battery that lasts for decades in many cases can outlast the equipment that it was originally designed to power. So from an economic standpoint lead acid, NiCd and other technologies have been deemed "good enough" and are the predominant technologies in use today even though they do not last as long as a Nickel/Iron counterpart. Nickel-Iron battery
These batteries do have limitations that make them less suitable for vehicular use such as
low specific energy, poor charge retention, and poor low-temperature performance.
since a residential or commercial solar pv installation is stationary, specific energy isn't a concern, the charge will only be needed to pull you through a night or a couple cloudy days and the batteries will be stored in a climate controlled area so they should be awesome for the task.
Apocalypse Cancelled, Sorry, No Ticket Refunds
solar subsidy for homeowners in Arizona is the power companies themselves.
it should be added, it is because of a requirement in state law that they collect a "renewable energy" fee, and use that to invest in these resources. They will only give rebates to owners with grid tie systems with no batteries.
Well, what about coal. You managed to talk trash like you know something about electric generation but you failed to mention how coal is somehow subsidized. You even managed to insert Bush and McCain in there. I'm waiting for the Obama will save us all line. I actually think it is funny how people claim the army protects this, Bush that McCain this and what it boils down to is My poor little pet projects aren't competitive enough to compete.
The bottom line is that prices are the way they are based on a history that stretches far beyond your age. If someone wants to compete with energy, they have to compete with anything that is done to that energy or to get it or to manipulate it. Nothing unfair is going on here. Wind and solar have the advantage of no fuel costs which more then compensate for any oil subsidies. I'm seriously amazed at arguments like yours that effectivly say raise the costs of X so Y can compete. It is contrary to our entire system of lowering the cost of Y to compete with X.
You managed to talk trash like you know something about electric generation but you failed to mention how coal is somehow subsidized. You even managed to insert Bush and McCain in there.
Tax breaks are given for coal mining. And it's not just some environmental website saying that. Even the CATO Institute, a Libertarian think tank, says coal is subsidized. Bush has proposed subsidizing clean coal as well as nuclear power. McCain has pledged to provide $2billion for clean-coal.
I'm waiting for the Obama will save us all line. I actually think it is funny how people claim the army protects this
I find it funny, actually stupid, when people "ass"ume I support Obama. In fact as of now I'm voting for the Libertarian candidate Bob Barr and during the last presidential election I supported Michael Badnarik. Actually since 1988 when Ron Paul ran for president as a Libertarian Party candidate I voted for the LP candidate except in 2000. As far as I'm concerned both Democrats and Republicans are half right and half wrong. Democrats what to control businesses whereas Republicans want to control people's lives, especially Christian Conservatives. And both are parties to the War on Drugs.
The bottom line is that prices are the way they are based on a history that stretches far beyond your age.
And how do you know how old I am? You can read minds? I doubt it as you "ass"umed I supported Obama.
Nothing unfair is going on here.
It is unfair when you have to compeat with an industry that receives government subsidies but you don't, or receive more than you do. I won't go over the rest because you're so good at reading minds to think I don't support a free market.
Falcon
Should there be a Law?