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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.'"

20 of 370 comments (clear)

  1. The old green question by gilgongo · · Score: 5, Interesting

    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?"
    1. Re:The old green question by Anonymous Coward · · Score: 5, Interesting

      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?

      We can answer anyway without even RTFA. The summary says that the cells are made out of glass (not hewn out of a crystalline ingot of silicon). Assuming 10% efficiency and 20% availability of sunlight (due to weather and geometry), you get approx 20W/m^2, or 1 kWh every two days.

      Given that glass beer bottles cost a few cents each, a square meter of glass probably takes no more than a few dozen kWh of energy to produce. Even if the vapor deposition doubles or triples that, you still would end up with an energy surplus after just a couple of months of operation.

    2. Re:The old green question by c1t1z3nk41n3 · · Score: 2, Interesting

      Don't forget the CdS and CdTe. Where do those come from? Are they expensive or cheap to make (regarding both energy and cost)? Hopefully they are cheap enough that your analysis holds cause we've been told for too many years that solar power is going to be a viable option and I hope it's finally about to come true.

    3. Re:The old green question by Anonymous Coward · · Score: 1, Interesting

      I'm afraid your mistaken. There's more than just glass involved ($1.14/W is cited in the article as the manufacturing cost).

      1. How much energy does it take to mine & transport the materials (cadmium, tellurium, & silicon, nitrogen gas).

      2. How much energy does it take to heat the first chamber to 600 degrees C.

      3. How much energy does it take to vaporize CdS (700 C).

      4. How much energy does it take to cool it. How much energy does it take to transport the cells to the final destination.

      Also, note that each step requires energy generation itself, therefore forming a recursive chain (i.e. it takes energy to produce energy). Since many of these don't terminate at renewable energy, at least for now, you'll have to factor in the contribution of the appropriate fossil fuel, nuclear, & natural gas energy production chains.

      Hence the complexity of the question - it's probably unanswerable in an exact sense, but I'm sure an accurate & reasonable predication could probably be estimated.

    4. Re:The old green question by Khyber · · Score: 2, Interesting

      Well, if they were made by solar-powered plants, we wouldn't have to worry about that,would we?

      --
      Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
    5. Re:The old green question by ScrewMaster · · Score: 2, Interesting

      No argument ... plus if you look at the whole picture of government subsidies, the tax breaks the oil outfits received should also be counted.

      --
      The higher the technology, the sharper that two-edged sword.
    6. Re:The old green question by Firethorn · · Score: 2, Interesting

      there's plenty of motivation to eat that delta in profit, especially for a public company as in this case.

      And said profit can be used to expand the company- increase production, research increasing efficiency and decreasing costs, not to mention paying back the investors.

      Making mad money can also encourage others to get into the industry.

      After all, the market for $2/watt panels is likely 4X that of $4/watt panels. And orders of magnitude more if they can manage to make $1/watt panels - installed, since that's the price point for commercial power parity.

      Though if you start digging into baseband power too much, the cost for commercial power will rise. Of course, peak power demands for most of the country happen during the day, so having a supplemental power source during the day helps.

      --
      I don't read AC A human right
    7. Re:The old green question by Locutus · · Score: 2, Interesting

      the problem is that they are only getting about 10% conversion efficiency out of their panels. What this means is that you'll need more square footage of panels than say 15% efficient panels. That means more roof space, more racks/rails, and more panels with all their frames and wiring.

      they say a theoretical 20% efficiency is obtainable but when you have subsidized orders out to 2012, it will only the the competition that'll force them to try harder to get the efficiencies up. Right now, they are making money and looking to expand manufacturing.

      LoB

      --
      "Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
  2. Their secret: unrevealed by StrawberryFrog · · Score: 2, Interesting

    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

    So, what's the secret to their secret?

    --

    My Karma: ran over your Dogma
    StrawberryFrog

  3. Re:The old black question by dubbayu_d_40 · · Score: 4, Interesting

    What's a better use of oil, making persistent sources of energy, or driving to 7-11 for nachos?

  4. Arizona! by copponex · · Score: 3, Interesting

    Well, a smart idea would be to move all of our high tech manufacturing to the hottest deserts we have. You can build earth sheltered factories to save on A/C, cover the roof and surrounding area with solar panels for virtually unlimited electrical supply, bury some flywheel energy storage to keep necessities going at night. If solar panels turn out to be unsustainable, simpler thermal power plants could be used.

    You have an endless supply of sand for glass and silicon. You make non-perishable goods that can be moved out slowly and efficiently (solar/thermal powered electric rail or whatever). To make it really sustainable you could use the same transportation to import recycled or recyclable plastics for the rest.

    Our current answer is using fuel that's guaranteed to run out. We should shop direct for our energy.

    1. Re:Arizona! by TubeSteak · · Score: 2, Interesting

      Well, a smart idea would be to move all of our high tech manufacturing to the hottest deserts we have. You can build earth sheltered factories to save on A/C, cover the roof and surrounding area with solar panels for virtually unlimited electrical supply, bury some flywheel energy storage to keep necessities going at night. If solar panels turn out to be unsustainable, simpler thermal power plants could be used.

      You're forgetting one thing: water

      Hi-tech industry is insanely thirsty and water is the one thing you will not be finding in the dessert.

      --
      [Fuck Beta]
      o0t!
  5. Not everyone wants to live in lower Manhattan by Anonymous Coward · · Score: 1, Interesting

    I like New York City just as much as the next guy (hey its a ton of fun when you're in your twenties and don't have any responsibilities), but the real price of living there is not paying $11.00 to drive a car, it means living in places the size of lunch boxes (that is, unless you're filthy rich)

    I for one, like the fact that when I grew up that I didn't have to share a bedroom with my siblings. I don't intend that my kids have to share bedrooms. And that means, living in a place where most people have to drive (though I am privileged enough to be within biking distance of my job)

    But hey, not everyone is that lucky.

  6. Re:Obama's "Manhattan Project" On Alternative Ener by Anonymous Coward · · Score: 1, Interesting

    I live in Atlanta, and I can tell you that these jerks that build 5-bedroom houses outside the city for 2 people to live in should be forced to ride bikes 30 miles in the sun to get to work. If you want to work here, park here, pollute here, pee here, etc... you should live here. The problem with the "REAL world" is that people think they shouldn't be accountable. Meanwhile, lakes are drying up, and air quality is deteriorating. The sense of entitlement will go away once things finally get bad enough to scare people in their own homes.

  7. No objection to a solar powered solar panel plant. by Firethorn · · Score: 3, Interesting

    Actually, the biggest portion of glass manufacturing is, of course, heat. You wouldn't want to use 10% efficient cells to produce electricity that goes directly to an electric resistance element to make that heat.

    Instead, you'd want to build a solar furnace - using mirrors and lenses and such you can get 90% efficiency, and using panels even cheaper than this.

    The trick would be the substantial start-up time in the mornings. Due to the heat levels involved, you'd be wasting a lot of energy each day heating the equipment up again.

    So either you have to find a solution for this, or use natural gas or whatever during the night to keep production up. This isn't bad as long as you still get more energy out of the resultant panels, etc...

    --
    I don't read AC A human right
  8. subsidies from private industry by raygundan · · Score: 2, Interesting

    The biggest source of solar subsidy for homeowners in Arizona is the power companies themselves. They'll pay for roughly half of your installation. My guess is that this is just smart infrastructure investment for them-- you foot half the cost and handle the maintenance, but they know the panels aren't moving once they're installed.

  9. Re:No objection to a solar powered solar panel pla by rossifer · · Score: 2, Interesting

    The trick would be the substantial start-up time in the mornings. Due to the heat levels involved, you'd be wasting a lot of energy each day heating the equipment up again.

    What you need is a thermal storage system and good insulation of your hot gear. Since they're talking about using molten salt as well as other substances like hard pitch (incredibly high boiling point) as thermal storage to allow solar power plants to produce power over 24 hours, I'd say the solution to the problem is at hand.

    And you're 100% correct that you should keep the solar power in thermal form. Thermal solar is much lower cost and you don't have the transformation losses that you mentioned. All you need is glass with aluminum/glass coatings for the mirrors along with an efficient thermal transfer/storage system and you're off to the races.

  10. Mojave Desert by falconwolf · · Score: 3, Interesting

    Forbes mentions that Mojave Desert real estate is becoming more valuable because many companies want to build solar facilities there.

    It's not just solar farms that are sprouting up in the Mojave, wind farms are as well. Actually there's one wind farm that virtually sat there silent back when CA had those rolling blackouts because the transmission capability wasn't there.

    Falcon

  11. Re:Obama's "Manhattan Project" On Alternative Ener by Anonymous Coward · · Score: 1, Interesting

    you propose farmers pay out the ass for their stuff, which then makes food more expensive, and then you will likely complain that food prices are causing too much inflation and the poor are suffering because they cant afford to eat. Some already complain about that. Raising fees on the very things that farmers require to get the food in a condition where you can eat it does not seem like a suitable answer.

    Sometimes the thing you hate is also the thing you rely on. And your comment about letting the market decide, when the government sets taxes and tariffs that is not the market deciding that is the government. Your example is *not* one where the market has much say.

    Oh and just in case I wasnt clear, farmers *need* vehicles, they need to mend fences, they need to plow and till fields, they need to be able to do a lot of things that currently require petroleum based fuels because nothing else offers the same torque. The same goes with the trucks that transport the stuff to market, they are diesel because it not only gives better mileage but also better torque so they can haul the loads of food (and other products) that are sold each day to provide jobs for many people, as well as stuff to eat when they get hungry.

    If you want 0 cars in NYC I am fine with that, it will be fewer people to feed and the rest of us can see a discount on our food prices. Somehow I dont think you envisioned signing a death warrant for everyone and no path does not take pallets of food as cargo, even if they did how would it get to the markets once there (there is the amtrak tracks that have been there for a decade or so).

    bonus: my captcha was dumbbell

  12. Re:Oil != electricity by Firethorn · · Score: 2, Interesting

    Where I live, in Southern California, I believe SCE generates our electricity from oil and natural gas. Oil comes from oilfields.

    You believe. Per SCE's site, it's "These resources include natural gas, a fossil fuel; falling water in hydroelectric plants; nuclear energy and renewable resources, like solar and wind."

    A coal plant was shut down 3 years ago, due to failure to obtain new permits, rendered uneconomical due to increased pollution control requirements.

    Oil is not listed.

    Natural gas comes from oilfields and natural gas fields.

    While NG does come from fields much like oil, it doesn't get shipped over here from the middle east. Production is domestic. Thus, engaging in wars overseas, for oil or not, won't have an effect on NG supplies.

    The WSJ article you link to is talking about direct, overt government subsidies. Those aren't the subsidies I'm talking about.

    Then which ones are you talking about? The ones where they aren't taxed like they should be for the environmental harm they cause? Or the portion of the military budget supposably spent to secure supplies?

    --
    I don't read AC A human right