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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.'"
It's probably unanswerable, but I wonder how much energy it takes to make these cells, and how long it takes for them to offset that?
"And the meaning of words; when they cease to function; when will it start worrying you?"
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.
So how much cadmium is needed, and how much leaks during the manufacturing process? Given that the opposition to nuclear power worries about toxic materials that decay with time, one would imagine there would be some concern about carcinogens that remain a danger forever, and cannot be destroyed.
What's a better use of oil, making persistent sources of energy, or driving to 7-11 for nachos?
Maybe you should have spent two hours reading the article - you might summarize it correctly then.
The article states that current silicon photocells sell for around $3-$4 per watt.
The new CdS/CdTe cells cost $1.14/W to produce and sell for $2.45/W.
To reach "grid parity" they need to reduce the manufacturing costs to $0.60-$0.75/W and increase efficiency from "over 10 percent" to over 12 percent. The maximum theoretical efficiency for CdTe cells is over 20% and cells with an efficiency of 16.5% have already been made.
WE just had a spill caused by human stupidity and penny pinching [oil tanker in the Mississippi that leaked all that heavy oil after a barge hit it] and so I have no faith in the Prince-William-Sound fouling oil industry to not have major accidents and ruin our common coastlines and all the wildlife and environments that live there. You're missing the point entirely. Oil is not a long-term solution. Why waste another dime on trying to extend the supply. We have clearly had something change in our weather patterns. We know oil is a fossil fuel that is destined to run out. Look at them flailing in China to clean up their air in time for the Olympics. Oil is just bad all around. So, according to your view, it is the best choice to direct our attention towards squeezing out those last few drops of oil, which--according to the 80-20 rule--will be the hardest, most expensive and lease safe of all? You're short sighted. To use an analogy that would be understood by all the slashdotters, you're the guy whose advocating that we rebuild our company's systems in COBOL rather than Java/.NET/ or whatever newer. Coal and oil do not need time or attention wasted on them. They are dirty, and only enrich a few people at the top of coal companies. We need diverse and varied sources of energy that are renewable. We need to try several things and let the marketplace choose which ones are the best. The real problem is that the oil industry is allowed to dump a byproduct of their commodity into the atmosphere and the waterways without accounting for that damage. If you accounted for the damage oil is doing to our environment, and made oil companies sell their product while paying for that damage, we would all see that the current petroleum-oriented economy is terrible. Anybody who roots for more oil drilling is just some deluded troglodyte who really doesn't care what happens to this world as long as they can get rich in it, and "have theirs". Well, we've had enough of people who are willing to get theirs even if it means they have to go out late Saturday nights and tip over a 50-gallon-drum of toxic waste into the local creek. If it saves them some money, they're all for it. We've had enough of that type of bastard.
Currently you can expect a home solar panel installation to pay for itself within 7 years (here in southern Ontario). If you combine it with wind turbines you can get your money back sooner, and if you spend the extra to be able to sell electricity back to the grid, you can get a payback much sooner because Ontario hydro (the power company here) pays you more than it would charge for the electricity (no distribution fee).
Ideally you want the installation to last for 10 years or more without significant failures, though.
Often "thinner and cheaper" translates to "more easily broken" and "less reliable" - for example, when the units flex in high winds. So my main worry would be about the expected (and achievable) lifetime of the units. Maybe if they gave a five or ten year warranty I'd be OK with it.
Live barefoot!
free engravings/woodcuts
I think you may be seriously underestimating the deliciousness of nachos.
Albeit not from the 7-11.
The reason none of these things have gone on line is because of the attitudes of people like you. There has been no concerted investment, ala the Manhattan Project. In lieu of any concentrated, directed effort to achieve a goal, nothing gets accomplished.
The sun shines reliably for a large fraction of the day--why not invest in that?
I find it curious how your standards of acceptability change: in the case of the alternatives available: switch grass, solar, wind, you play the pessimist. In the case of oil available off the coasts, suddenly you're an optimist. The US Department of Energy [you know, the one with all the Bush appointees in it] has said that 1.) offshore oil will not enter the supply chain for ten years minimum, not "a couple years" [implying 2], as you allege.
Next you toss out the red-herring [meaning irrelevant] point of the Chinese drilling in Cuba--a claim which has been shown to be false so clearly that former GOP Candidate Rudy Guilliani himself uses future tense to describe this alleged problem, which is still a red herring. Do two wrongs make a right? [China allegedly drilling around Cuba and the US drilling off Florida?]
Again, when you address the oil industry, it's all solid to you. When it comes to alternatives, it's "pie-in-the-sky". What are you, an oil-industry flack? You reluctant to learn new things or something?
Though Nuclear does have the benefit of no greenhouse gases, it still has the same fundamental problem that oil does: it's business model is predicated on NOT dealing with its wastes! We STILL doe not have a solution to the incredibly toxic wastes we've been generating for decades. The only solution is to hide the waste. You think this is a viable alternative? Or, are you a Nuclear Energy devotee who has some business interest in that industry. When you advocate dirty technologies, how can we take you seriously?
By the way, I lived in Houston and there is mass transit which I used while working for HP
. And the solution is not--duh--biking 30 miles, it's moving closer to your work and downsizing your stuff.
As I can re-iterate: I have lived all over the United States and this model in NYC is the only one I see as being viable. I've lived and commuted in Omaha, Phoenix, Houston, Cincinnati and Salt Lake City. I always chose to live as close as possible to work.
Such name calling as labeling environmentalism "psychobabble" is convincing fewer and fewer people, my friend. The babble is coming from you fools who seem to prefer fouling your own nests.