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A Step Closer To The Optimum Solar Cell

Posted by timothy on from the warmth-too dept.

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."

17 of 107 comments (clear)

  1. No Solar For You! by Henry+V+.009 · · Score: 2, Insightful

    The calculated efficiency of a single-junction solar cell made with this material would be a remarkable 57 percent. But while the single-junction architecture is elegantly simple, many questions have to be answered before ZnMnOTe or any of its highly mismatched cousins prove they can do the job.

    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.

    1. Re:No Solar For You! by Councilor+Hart · · Score: 2, Insightful
      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.

      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.

    2. Re:No Solar For You! by Henry+V+.009 · · Score: 2, Insightful

      Energy expense is the thing. Especially once the cost of mining rises due to the increasing expense of oil. (All that heavy equipment runs on gasoline, not electricity.)

    3. Re:No Solar For You! by Intrigued · · Score: 1, Insightful
      We won't have to rebuild with coal. They oil companies will reengineer for mining Methane clathrate out of the ocean and buy out the thermal depolymerization industry long before they relenquish to the coal industry.

      Don't underestimate their ego.

  2. Something wrong with nuclear power? Oh yeah... by Anonymous Coward · · Score: 1, Insightful

    "Something wrong with nuclear power?"

    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?

    1. Re:Something wrong with nuclear power? Oh yeah... by Councilor+Hart · · Score: 4, Insightful
      t is extremely expensive and dangerous,
      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.

    2. Re:Something wrong with nuclear power? Oh yeah... by ttfkam · · Score: 2, Insightful

      ...gas at a few hundred degrees will certainly burn, ash will bury.

      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 groundwater or air. Did you know that radioactivity in and around coal plants is higher by two orders of magnitude than those found outside a nuclear power plant? Did you know that the NRC rules for radioactivity outside a power plant are lower than the ambient radioactivity found in nature? Did you know that Grand Central Station in NYC would be automatically disqualified as a site for a nuclear power plant simply because the amount of radioactivity in its granite construction exceeds NRC maximum levels?

      "Yes, the American taxpayer has paid $1 billion [as of 1980] to research nuclear safety ... the American taxpayer also pays $1 billion, not total, but year after year, to Black Lung victims -- not to cure or eliminate it, but just to compensate its victims."

      "... the US government ... has very few enterprises that make money. But one of the them is uranium enrichment, for which the fuel manufacturers pay through their noses, and another is Price-Anderson insurance, the premia for which are paid by utilities, partly to private insurance pools, partly to the US government. The private insurances pay first, and they have so far paid $400,000 for 26 minor claims; Uncle Sam hasn't paid anything yet (and probably never will), but sits on a fund of $8 million of as yet unused premia. And, of course, the utilities pay taxes -- local, state, and federal -- with the stockholders paying a second round of taxes from their dividends. You call that a subsidy?"

      - The Health Hazards of Not Going Nuclear by Dr. Petr Beckman. © 1980

      The only reason nuclear could be more expensive (though still cheaper per kilowatt than solar) is because of the much expanded regulations on the nuclear industry that do not exist in the other industries.

      A hairline crack was found in the plumbing of stand-by equipment in a nuclear power plant some years back. This was found by visual inspection. There was no leakage -- even taking into account that this was not radioactive water in the pipes. So what was the NRC's decision? Take down this plant and every nuclear plant in the country with the same design -- I believe something like 22 of them at the time. And what did they find? The one hairline crack: the one originally found by regular visual inspection. If ANY industry were held to the same safety standards as nuclear, they would be bankrupt. As it stands, nuclear is still competitive. If such ornerous (ridiculous) safety checks were not in place, it would be substantially more reliable and cost effective than any alternative.

      Well, that and the fact that rabid Greens have lobbied successfully against breeder reactors in the U.S. which could make nuclear power generation even more profitable than it is today. IFR reactors could process the "waste" waiting to be stuck into Yucca Mountain AND repurpose nuclear warheads for power generation -- a proper end in my opinion to a large portion of our current nuclear stockpile.

      But no. Nuclear is BAD.

      Or did you have delusions that solar power would save the day or that coal is better than nuclear?

      Please do not misunderstand. I welcome increased usage of solar, wind, and to some extend tidal, but these are not enough to supply 3,720 billion kilowatt hours of po

      --

      - I don't need to go outside, my CRT tan'll do me just fine.
  3. The only equation that matters by Dr.+Bent · · Score: 3, 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.

    1. Re:The only equation that matters by SB9876 · · Score: 3, Insightful

      The fact that most people miss is that solar cells have started to push past this goal. They now take less energy to manufacture than they capture in their lifetime (always a bonus), and the cost per kWh is pushing down to 2-3 times grid electricity. Given that solar cells have demonstrated a steady decline in cost for the past few decades, chances are good that we'll start seeing large scale adoption in the next decade.

      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.

    2. Re:The only equation that matters by Anonymous Coward · · Score: 1, Insightful

      Are you saying that people won't invest in something until their return is at least tax free 20%?

      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.

  4. Re:The Socialist solution by Smidge204 · · Score: 3, Insightful

    Under Socialism, R is also 0, but M might not be. You pay for it alright, just not directly.

    So under Socialism there is *no* incentive to use them other than political adgendas.
    =Smidge=

  5. Re:...when I see it by julesh · · Score: 3, Insightful

    Largley because the incremental process tends to catch up with it before the new idea becomes commercialised.

    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...?

  6. The problem with fision has a name... by Anonymous Coward · · Score: 1, Insightful

    ...it's Chernobil.

  7. We did the time warp again? by dbIII · · Score: 3, Insightful
    Until then, solar power will be a technical curiosity for use in special situations (outer space)
    Ever seen a pocket calculator? They don't plug into the wall anymore - they started to run on batteries, and now run on solar power. Marine navigation lights don't burn parafin, they have little solar panels on top of them. A lot of microwave relay towers are solar powered. Yachts have solar panels. I would have said the exact same things in the 1990s and it is now 2004. A better solar cell helps in those applications where they are already in use, and makes other applications easier to implement.

    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.

  8. Re:Solar energy . . . the big picture . . . by dan42 · · Score: 2, Insightful

    The panels you can buy and use for your house today have a 3-4 year energy payoff. (ie, they make an amount of energy equal to what was put in to them in production)
    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 pollution.

  9. Re:...when I see it by Christopher+Thomas · · Score: 2, Insightful

    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...?

    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 grow it epitaxially.

    As for long-term cost prospects, we're already mass-manufacturing similar highly-mismatched alloys for LEDs (anything with Ga/N/As as constituents, for one), so I'm confident costs will come down eventually.

    Very nifty technology.

  10. Try Low-Tech First by Shipud · · Score: 2, Insightful

    In many Mediterranian countries, water is heated using solar panels which utilize the greenhouse effect. The idea is that blackened water pipes are running through a glass panel installed on the roof, facing south. Hot water is stored in a tank. In summer, and in many winter months, this removes the need for heating water electrically. Coming to a sunny part of the US, I was pretty astonished not to find that. Well, at least not in Cali. Makes you wonder why how much this new development will be implemented.

    --
    /sdrawkcab si gis siht