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Power Businesses The Almighty Buck

Silicon Valley Startup Prints $1/watt Solar Panels 519

GWBasic writes "A Silicon Valley start-up called Nanosolar has shipped its first solar panels — priced at $1 a watt. That's the price at which solar energy gets cheaper than coal. While other companies have been focusing their efforts on increasing the efficiency of solar panels, Nanosolar took a different approach. It focused on manufacturing. 'The company [has developed] a process to print solar cells made out of CIGS, or copper indium gallium selenide, a combination of elements that many companies are pursuing as an alternative to silicon.'" The outfit also happens to be backed by Google, a fact that's getting some attention at tech media sites.
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Silicon Valley Startup Prints $1/watt Solar Panels

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  • by phrostie ( 121428 ) on Friday December 21, 2007 @12:36PM (#21780200)
    i was reading their webpage the other day and they only seemed to sell to large corporations or utilitiy companies. when will they start offering a consumer version.
    • by Rei ( 128717 ) on Friday December 21, 2007 @12:41PM (#21780298) Homepage
      Once their production capacity outstrips their manufacturing obligations. As per their website [], which I've been following (slowly) over the past couple years, you *could* get one right now [] off ebay -- their #2 print. However, it's being sold as a collectible item, a piece of history, with the proceeds going to charity. So, needless to say, the price is rather steep ;)

      This is huge news. Punch $0.99 a watt into the calculator [], and even good chunks of Alaska become economical for installations.
      • by smilindog2000 ( 907665 ) <> on Friday December 21, 2007 @12:57PM (#21780576) Homepage
        This is a huge milestone. However, the summary gets a couple things wrong: First, $1/watt panels aren't "cheaper than coal". Large coal consumers buy 2,000 pounds of coal for $50. Burn that in a crappy Bush-endorsed power station, and utilities can print money at $0.07/KWh. That's why coal is the #1 enemy in the global warming battle - not oil. The $1/watt goal makes solar utility power feasible in areas that currently have excellent sunshine (say southern CA), and expensive fuel (say natural gas). It's a huge step, but not the last step.

        The second error in the summary is the current price. The company claims they could sell $1/watt panels, but with 100% of their production for 2008 already purchased, what are the odds they're selling their stuff 4X below market value? Not a chance. The revolution's happening, but it will take a while.
        • by Rei ( 128717 ) on Friday December 21, 2007 @01:17PM (#21780846) Homepage
          Yes, it is cheaper than coal power, almost everywhere in the US. You can run the numbers [] for yourself. The problem with coal is that once you burn it, it's gone. The problem with traditional solar is that the capital costs are so high, you'll never catch up with the interest. When you cut the capital costs on solar significantly, it wins hands-down.
          • by smilindog2000 ( 907665 ) <> on Friday December 21, 2007 @01:48PM (#21781338) Homepage
            Thanks for the web site. It computes the break-even point for installing solar panels at home, and plugging in $1/watt makes it all work out quite well. I'll have to keep track of this link. However, from what I read, coal is still cheaper to burn for power in utility plants. I read that it costs utilities between $0.01 and $0.02 per KWh to produce when burning coal, even when taking the cost of the plant into account.
            • by mr_mischief ( 456295 ) on Friday December 21, 2007 @01:54PM (#21781444) Journal
              I'm frankly too lazy to do the math right now, but maybe they're counting on installations closer to consumption sites with less delivery loss. The cost of generation in large centralized plants is one thing, but line attenuation and impedance loss are another.
          • Re: (Score:3, Interesting)

            by dasunt ( 249686 )

            I am running the numbers.

            Coal is .08$ a kWh.

            So for $1000, that buys 1 kW of photovoltaic cells.

            If the cells are run for 12,500 hours at full capacity, the price is equal to coal. Past 12,500 hours of full capacity, that's cheaper than coal.

            That's 521 days of 24/7 sunlight, for almost two years. Rather unlikely on earth.

            The Google tells me [I]A 1 kilowatt peak Solar System will generate around 1600 kilowatt hours per year in a sunny climate and about 750 kilowatt hours per year in a cloudy c

        • by misleb ( 129952 )
          Also, I assume they have a patent on this process so we're not going to see any competition. At best we'll see them license the tech out to others... but probably with some kind of non-compete clause. Like the the licensee can't charge less for the panels or some dumb crap like that.

          • by Rei ( 128717 ) on Friday December 21, 2007 @02:08PM (#21781694) Homepage
            Actually, you'd be surprised. They have a patent on their *specific* process, but they don't have a patent on CIGS cells in general, and there are quite a few companies pursuing them. I doubt anyone will be able to hit Nanosolar's price point because not only is Nanosolar ahead in terms of commercialization, but I think their tech is the most promising CIGS cell tech. Even still, the competitors should be able to at least approach Nanosolar's prices, and -- here's the big deal -- since it'd be a decade at best before Nanosolar could sate the market's demand enough to lower prices to that $1/W level, its competitors production should help the prices fall faster.
        • Re: (Score:3, Insightful)

          by DaleGlass ( 1068434 )
          I imagine though that the $1/Watt isn't a $1/Watt in the panel's lifetime, but $1 for a panel that will generate 1 Wh, when used at full capacity.

          Assuming a lifetime of 20 years, a $50 panel producing 50Wh will produce 8760 kW at $.005/KWh, assuming it runs at full capacity 24/7. An actual real world figure would be several times worse, but that still comes out looking very good.

          • by Rei ( 128717 ) on Friday December 21, 2007 @01:56PM (#21781480) Homepage
            The calculations are a lot more complicated than that. You can check the source for the calculator (linked earlier) to get an idea of all that needs to be taken into account.

            The reported wattage of a panel is typically the amount of power it will produce when given 1000W/m^2 of sunlight and with the panel maintaining a constant temperature of 25C. 1000W/m^2 is basically your best-case situation here on the surface -- bright, crystal-clear sky on a summer day with the panel facing straight at the sun. Overall, the panel will average produce far less than its rating, but the exact amount is very complex to determine and depends on where you are and what your setup is like, so panels are rated in standard terms. Beyond that, there's also the "derate factor", which is the losses in your system apart from the panels -- wiring, terminals, etc, but most importantly, the losses in your inverter. 0.77 is a good derate factor. The derate factor drops with age. Panels also produce less power with age, but this effect is often overemphasized.

            Secondly, you're confusing watts and watt hours. Watts are a unit of power, while watt hours are a unit of energy (a Joule, another common unit of energy, is a watt second). If your panel is producing 1W, then it's producing 1 Wh every hour -- i.e., 8.8 kWh/year. But if it's simply a panel that's rated for 1W, and isn't on a heliostat, you'll probably get something like 0.5 to 1.5kWh/year, depending on where you are.
        • Re: (Score:3, Insightful)

          by dgatwood ( 11270 )

          It's $1/Watt, not $1/Watt-hour. $1/watt is $1000/kW divided by... say 8 hours of full sun per day... time 20 years. That will get you the kWhr price, or about 1.7 cents per kWhr, a fifth the price you mention for coal. Of course, you won't always get 8 hours of full sun per day in all locations, so the numbers are highly variable by location and time of year, but if your numbers are correct, that is significantly cheaper than coal in many cases.

        • by bodrell ( 665409 ) on Friday December 21, 2007 @01:42PM (#21781236) Journal

          This is a huge milestone. However, the summary gets a couple things wrong: First, $1/watt panels aren't "cheaper than coal". Large coal consumers buy 2,000 pounds of coal for $50. Burn that in a crappy Bush-endorsed power station, and utilities can print money at $0.07/KWh.
          You can't compare watts to kWh. They aren't the same units. But I went ahead and did the math for you.

          1 kWh = 3.61 x 10^6 J
          $0.07/kWh = 14.3 kWh/$ = 51.6 x 10^6 J/$
          solar panel = $1/W = $1/(J/s)
          3600 s/h, 24 h/d, 365 d/year --> 31.5 x 10^6 s
          51.6 x 10^6 (J/$) / 31.5 x 10^6 (J/year/$) --> 1.64 years (producing at full capacity) makes it cheaper than coal. Even if you only run at 25% capacity on average, taking into account varying daily solar intensity, the investment pays for itself in 6.5 years.

          Of course, your other points are valid; burning coal is bad, at least using the current technology. And that $1/W number is still theoretical, so if they're selling at $4/W, then it would take 26 years to be as cost-effective as coal (given constant energy costs; but that time would be much shorter if we have an energy crunch and prices spike--or another Enron-style price-gouging scam, for that matter).
          • by flaming-opus ( 8186 ) on Friday December 21, 2007 @03:25PM (#21782854)
            You're forgetting two very important things. In your math you're forgetting to amortize your capital costs. Basically you're assuming that you can get a 0% loan. In reality, paying for solar up-front, instead of coal as you need it, you need to tripple the cost of the solar, because of the interest you will have to pay over the 25-year life of that "loan".

            Secondly, solar provides great energy during the middle of the day. However, most residential electrical demand happens in the early evening, when people get home from work and turn everything on. Most industrial users of electricity need a constant supply, around the clock. Commercial users need electricity throughout the day, with a spike in the late afternoon as air conditioning demand increases. Solar-electricity provides for some, but not all of these needs. Storing solar energy in batteries, thermal storage systems, or mechanical storage systems doubles or tripples the cost again.

            Thus, even with $1/W panels, general-purpose solar power is still 8-10X the cost of coal. I'm terribly doubtful that solar power will ever be economically competitive with coal, UNLESS you factor in the ecological costs. Unless we start taxing utilities for the carbon that they emit, we will not see solar become competitive, beyond little feel-good projects, and home-hobbyists.
            • Re: (Score:3, Insightful)

              by bodrell ( 665409 )

              You're forgetting two very important things. In your math you're forgetting to amortize your capital costs. Basically you're assuming that you can get a 0% loan. In reality, paying for solar up-front, instead of coal as you need it, you need to tripple the cost of the solar, because of the interest you will have to pay over the 25-year life of that "loan".

              Ah, assumptions. Will coal prices stay constant? What about inflation, even if coal supply remains constant? And the 25 year figure was only for $4/W

        • by kestasjk ( 933987 ) on Friday December 21, 2007 @02:05PM (#21781648) Homepage
          It's tricky to convert between watts and kWh, they sound the same but one is a unit of power and one is a unit of energy. Power is energy per second, so it's like comparing the cost of a gallon of water with the cost of a spring.

          A kWh is like a glass of water, and a watt is like a trickle of water from a leaky tap. A 1 watt panel would take 1000 hours to make one kWh.
          If a panel lasts 1000 hours then you're paying $1/kWh, which doesn't compete with $0.07/kWh. If it lasts forever you're basically paying $0/kWh in the long run, so you might as well buy ~10^12 panels and forget about energy problems.
          This is why hydroelectric power is appealing: Once built they stay there generating power for only the cost of maintenance, the problem is there are only so many places where a dam can be built.

          In a nutshell more info is needed to know if this even counts as progress. What about the materials? Can you get lots of whatever semiconductor they're using cheaply? Does the $1/Watt panel become $1/ 0.01 Watts when it's not facing directly at the sun on a bright day in California?

          I'm not looking for any "revolution" from a small start up energy company.

          By the way this is an area where nuclear power could become an even better alternative: The big cost of nuclear power is building the plant and decommissioning it afterwards, the uranium is dirt cheap. The price of a kWh from a nuclear plant is made up mostly of the price of building and decommissioning the plant. If a nuclear plant's design can be made so the life is doubled the cost will halve. If a plant that lasts as long as a hydroelectric plant could be designed we could have power too cheap to meter.
    • Yahoo! (Score:5, Insightful)

      by Anonymous Coward on Friday December 21, 2007 @12:42PM (#21780318)
      I don't really know whether global warming is real and dangerous. Now just maybe I don't have to care.

      Can we conver Arizona with these (and use ultracapacitors for night power)? Please?
      • Re:Yahoo! (Score:5, Interesting)

        by explosivejared ( 1186049 ) < minus bsd> on Friday December 21, 2007 @01:01PM (#21780640)
        You sir are a genius. No really I mean it. I wish there were more people like you that put the ad nauseum hashed debate about warming or climate change or whatever to the side. There is a legitimate argument for a lot of different viewpoints about the climate. The area where there is no room for different viewpoints is on the limited nature of fossil energy resources. Whether or not you buy into anthropogenic climate change or not, you should support more efficient non-fossil fuel energy sources. Diversity is the key. For two long we've all of our eggs in one basket, and it hasn't been until recently that we've realized that come back and bite us. Cheap solar like this could go a long way to broadening available energy as we start to see the real issue with energy arise, namely how do we support a rapidly industrializing third world and a world population that will reach nine billion in fifty years. Quantity is a real problem. We've built our economies on cheap energy, and now we're gonna have to work to keep that going.
      • Re:Yahoo! (Score:5, Informative)

        by Rei ( 128717 ) on Friday December 21, 2007 @01:13PM (#21780802) Homepage
        Quite a few problems with that. :)

        For one, I can't picture production capacity catching up with demand enough to lower prices to that level for at least a decade, and even that would take a trenemdous expansion rate. There's no way Nanosolar is going to *sell* at $0.99/W when the current market price if $5.80/W and they don't have enough production capacity to meet supply. They stated that they can *turn a profit* selling at $0.99/W. They'll sell for $5.70/W, $5.60/W, or whatnot -- whatever's the most they can charge and move all their capacity. They're not idiots. They're going to earn every last dollar they can, and pump it into new production facilities. Only as the market becomes saturated will prices drop.

        Secondly, global warming is going to happen even if all killed ourselves today. There's too much inertia behind the problem. What we effect today is what things are going to be like in 2050, 2100, not the next decade or two.

        Third, this doesn't address vehicles. Still have to take care of that gorilla in the corner. It also doesn't address industry CO2 pollution unrelated to power demand, such as steel production. Still, it's a great start.

        Fourth, you don't need to cover a big expanse of desert at all. There's more than enough rooftop space in the world to meet demand. Example: China has 32521 square kilometers [] of urban area. Assuming 11% efficiency on these cells and 25% of that urban area being able to be coated in cells, and assuming an average insolation of 200W/m^2, we get a total power production of about 180 terrawatts. Current *world* demand is only 10 terrawatts. See where I'm going with this?

        Fifth, ultracapacitors are too expensive for power storage currently. We're still going to need baseload power production until a cheaper method of storing power can be found. One concept that I find interesting relates to electric cars. To charge a car quickly in your garage, you're going to need a home charging unit. Your house just can't deliver power nearly fast enough for a five to ten minute charge. The idea I read is to use those for power balancing: have them charge themselves when there's a glut of electricity and discharge into the grid when there's a shortage. In exchange, utilities would give consumers a significant discount on their power bill.
        • by Rei ( 128717 )
          Minor correction: cells this cheap would probably lay flat, aren't going to be heliostat mounted, and I didn't consider the derate factor, so that production figure is probably more like 70TW or so instead of 180TW. Still, you get the picture. Rooftop space is way more than enough to meet our needs.
    • Re: (Score:2, Insightful)

      by MrLogic17 ( 233498 )
      $1/watt? Cheaper than coal? I'm confused.

      Coal you burn once, and you're done. Easy price calculation.

      With solar, you buy the solar cells. And the regulators (Sunlight's variable ya know). And the battery packs, assuming you're not going directly back into the grid. And maint of said batteries.

      And the solar cells aren't producing 100% output for 12 hours/day. And the lifespan of these solar cells are an estimate.

      Don't get me wrong, I'm all for this. I'm just very suspcious of an apples to oranges com
      • To get apples to apples, compare the cost of the panel (1$ someday) with the production (mining, transport) cost of 1 Watt of coal.
  • by Anonymous Coward on Friday December 21, 2007 @12:38PM (#21780240)
    Of course coal also works at night.
    • A solution is a global energy grid. Sure, it may be daytime in the US right now, but it's night-time in India. Of course, there would be transmission losses, never mind the cost of insulated undersea high-voltage power lines, the cost of ninjas to fight the pirates who would threaten to hold the power lines hostage, and the cost of robots to keep the ninjas at bay.

      Seriously, though, power usage at night is much lower than during the day. We have other non-fossil-fuel energy sources that can be used to p
      • by rah1420 ( 234198 )

        A solution is a global energy grid. Sure, it may be daytime in the US right now, but it's night-time in India.

        And if the electric companies have any sense at all, a "global energy grid" should be keeping them up at night. If I were a betting man, I'd say within the next couple hundred years we could see feasibility studies on a global grid.

        • Re: (Score:3, Informative)

          by Red Flayer ( 890720 )
          I think we'll see studies as soon as we have the capacity for economically feasible distributed energy production (such as the solar cells mentioned here ramped up in scale). I think feasibility studies will be happening in the next fifty years. Decentralized power production is really what the power companies fear.
      • by hansonc ( 127888 )
        I don't know about you but I'm pretty sure my energy use peaks in the evening.... you know when it's dark and I have to turn on lights... and I'm home... and I'm heating my home... and doing laundry or washing dishes...
    • by sm62704 ( 957197 ) on Friday December 21, 2007 @12:53PM (#21780516) Journal
      So do rechargeable batteries.

      This makes me think once again that the 20th century was an abberation.

      Before the 20th century if you wanted to know what time it was you pulled a clock out of your pocket. In the 20th century you looked at the clock on your wrist. After the 20th century you pulled your phone out of your pocket.

      Before the 20th century musicians made their money by performing. During the 20th century many musicians made their money by recording music. After the advent of the internet musicians will once again make their money by performing and use their recordings as advertising (as everybody but the RIAA bands do now).

      Before the 20th century there were few wires. During the 20th century wires were everywhere - strung from poles, on your phone, TV, computer eqiopment, everything that used electrity. After the 20th century everything is wireless.

    • Re: (Score:3, Interesting)

      by Slugster ( 635830 )
      This is true.

      There's only three problems with solar power installations: the cost of solar cells, the cost of inverters, and the cost of storage batteries.

      Solar cells without storage batteries is only helpful for things that you only need to run during peak daylight hours--or if you live in an area that doesn't have enough power capability for peak-load use times (such as California, with its regular rolling blackouts in certain areas during the summer).

      The huge costs of residential whole-house sola
  • Will they last, are they durable, is it flexible or rigid? Lot of questions left to answer on the solar front.

    However, if I can shingle my roof with these things, all the better!
  • Eventually. (Score:5, Insightful)

    by xlsior ( 524145 ) on Friday December 21, 2007 @12:39PM (#21780254) Homepage
    From the article: Roscheisen said the manufacturing process the company has developed will enable it to eventually deliver solar electricity for less than a dollar per watt
  • by tinrobot ( 314936 ) on Friday December 21, 2007 @12:41PM (#21780296)
    Once they get their manufacturing up to speed, prices will most likely get even lower.

    Too bad they're already sold out for the first 18 months of production, because at those prices, you could make a typical house solar for about $1500-2000 for the panels, plus another few grand for installation and hookup. At that price, it makes a lot of sense.
    • I think you're off by almost two orders of magnitude. A typical, all-electric house (no nat gas, LP or oil) is going to have a minimum of one 200A-240V panel, and will likely have two (50- or 100kW total). Iirc, the rule of thumb for inverters and storage is a dollar of that backend stuff for every dollar of panel (that could also be off by quite a bit...and probably not in the homeowner's favor). Once you get that part figured out (say $100k) then all you have to do is get 4000SF of southerly facing rooft
      • Is it just my observation, or are there way too many stupid people in the world?

        Everyone laments the number of stupid people, but no one stops wonder if they're one of them. :)

      • I love the assumptions. Flat roof vs. Pitched. Southern facing walls can also hold solar panels. Solar panels can go in the yard, on storage buildings, carports etc. I know a few people right now who have solar only houses, with Propane for cooking and back-up heat, with a lot less than 4000 SF of solar panels. A lot less. Perhaps you, or the majority of USians would need a) more, or b) to use much less. The rule of thumb you quote would not necessarily hold true for a new technology. The inverter i
        • Re: (Score:3, Insightful)

          by Rei ( 128717 )
          Indeed. Rules of thumb are awful for solar installations because the power production, geometry, and needs vary so much. You really need to calculate it for your given setup. Offgrid is a huge premium to pay, and with panels this cheap, it's now going to be an even bigger premium. Not only do you have to pay for the batteries, but also their maintenance, replacement, and the charge controller, which at $5.80/amp, isn't negligable either. For on-grid, panels are typically the overwhelming portion of the
      • Just because someone has a 100kw panel doesn't mean they use 100kw. You'd pop every circuit breaker in house if you used that much.
    • Re: (Score:2, Interesting)

      by leet ( 1202001 )
      I've been looking seriously into going solar on my house. I live in Arizona and it costs about $18,000 to $20,000 for the initial installation. You end up with about $4,000 out of pocket once the conversion is done and you've gotten the tax breaks, etc. The process of installation takes about 6 months. I don't have the start up capital to do it.

      As soon as I can I'm going to because I'm sick of the high electric bills in the summer. I can do nothing about it because you have to run your air conditioner
      • Re: (Score:3, Informative)

        by nmos ( 25822 )
        I'm not a greeny either, I just don't like the cost. I long for the day when I don't have to worry about this anymore and I can run whatever appliances I want, whenever I want. As it is now I try to run my vacuum cleaner and laundry on weekend only when the power rate is lower. I would very much like to do things on my schedule and not the power company schedule.

        If that's your goal then you can pretty much scratch solar off you list. One of the first things people learn when they start to look into solar i
  • Inaccurate summary (Score:4, Informative)

    by Chainsaw Karate ( 869210 ) on Friday December 21, 2007 @12:42PM (#21780310)
    From the article: "Roscheisen said the manufacturing process the company has developed will enable it to eventually deliver solar electricity for less than a dollar per watt"

    Nowhere in the article does it mention the price of the first run of panels. I'd imagine they are much more expensive than $1/watt.
  • To mark the occasion, Roscheisen said the first commercial panels will get special treatment: the first that came off the rolls will become part of a Nanosolar exhibit; the second will be auctioned off on eBay

    And here is the link []!
  • Here in Springfield, our power plant [] runs on coal. Since my electricity's cost is not only the coal, but the maintenance and transmission of electricity, it should be cheaper to line my roof with these things than to buy it from Mr. Burns [] (he's the one in front of the giant check, on the left. He's also the one in the first linked picture, also on the left).

    But at a dollar per watt I'd pay $20,000 for a single circuit... oh wait my math is wrong. At 100 volts that aould be $200. So I could power my whole ho
    • So I could power my whole house for a one time investment of less than $2k? Sounds too good to be true. What's the catch?

      Powering it at night :-)

    • 200W at 100V is only 2 amps. Most household circuits are 15A, so that would place the wattage at 1800W... So $1800/circuit, not including inverter losses.

      But then solar panels only make juice during the day, so you'd need at least double that to power the whole circuit all day.

      Realistically, you could power a house off of an average 8 kilowatt without much conservation, and probably get down to around 5 or so with it, and lower still if you make some sacrifices.

      But then you have to get that power on AVERAGE
    • Re: (Score:3, Informative)

      by Tiroth ( 95112 )
      You were right the first time: 220V * 100A = 22000W = $22000 @ $1/W.

      Of course, most designs would require a much smaller up-front investment, because you'll run off the grid when you are using the dryer/stove/ironing/AC, but take advantage of cheaper power for the base load (lights, computer, fridge).
    • by sm62704 ( 957197 )
      I need coffee, can't tell my right from my left. In the above post change "left" to "right". Damned lithograph class I took in college fucked me up for life!
    • Re:DOH! (Score:5, Informative)

      by ivan256 ( 17499 ) on Friday December 21, 2007 @12:58PM (#21780582)
      You have to clear the snow off of it, it only works when the sun is out so you need a crap-load of batteries or $15-20k worth of automated switching equipment which allows you to be simultaneously connected to the grid without electrocuting the lineman who is working on your pole and thinks the power is off, you probably need to multiply your number by at least 4, because you need to generate power for the 75% of the time you're not getting good sun in the 25% of the time that you are, and you need some pricey inverters if you want to run devices designed for 110V AC...

      Additionally, they're not actually $1/watt. That's the theoretical cost if they are able to ramp up production as planned. If you had $1 for every startup that failed in that phase, you wouldn't care how much your solar panels cost.
      • An entire grid-tie solar installation for my house was bid at $18-20K.

        If the grid-tie switching equipment costs $15-20K, I must be getting the panels and labor for free.
      • Re: (Score:3, Informative)

        by Lumpy ( 12016 )
        No. my syncing inverter cost me $3500.00 it doesn't do the FUD of "electrocuting the lineman" like people enjoy using out there. No Line tied inverters were capable of doing that for over 15 years now.

        $3500 syncing inverter + $2000.00 of PV array at those prices = a significant savings and almost ZERO maintaince costs or time. Washing them off twice a year with a hose is plenty. and my array never had to have the snow removed. what idiot leaves the PV array tilted that high in winter?
    • Re: (Score:3, Informative)

      by hypnagogue ( 700024 )

      So I could power my whole house for a one time investment of less than $2k? Sounds too good to be true. What's the catch?

      Depends on what your expectations are. Were you planning on actually having power during the other 20 hours of the day? If so, then you'll need to have a very large battery array, and about 6 times the solar capacity you've calculated in order to fully charge the batteries during the relatively brief peak hours. Add in a massive charge controller and inverter, and you are pretty clos

    • Here in Springfield, our power plant runs on coal.
      I could have sworn Springfield had a nuclear power plant...
    • The catch? you still can't get one to power your house with. That's a pretty big catch (complete unavailability of the advertised product or service)...
  • I read both the linked articles, but I didn't see a ref to $1/watt... What did I miss?
  • I have always appreciated the self deprecating humor and the jolly view of things indicated by that unix tool, Yet Another Compiler Compiler. I wish someone would name their solar cell, yet another solar cell, just for the kicks.
  • Have to ask, the gurus or would be gurus:

    When companies report that their solar solution costs $X a watt, is this figure a steady watt/hour figure (e.g 1000W = 1kw/h) during which time the sun is shining on the pannels, or watts generated per hour of direct sunlight, 8 hrs of direct sunlight, every odd Tuesday, what? I always assumed it's a steady watt/hour figure but in this case $1000 would give you 1KWH while they were running, which gives you (assuming you have a battery storage solution) a production
    • by DragonWriter ( 970822 ) on Friday December 21, 2007 @01:02PM (#21780652)

      When companies report that their solar solution costs $X a watt, is this figure a steady watt/hour figure (e.g 1000W = 1kw/h) during which time the sun is shining on the pannels, or watts generated per hour of direct sunlight, 8 hrs of direct sunlight, every odd Tuesday, what?

      Watt is a unit of power, not energy. So its watts (presumably, in some specified lighting conditions), not "watt/hour".

      I always assumed it's a steady watt/hour figure but in this case $1000 would give you 1KWH while they were running, which gives you (assuming you have a battery storage solution) a production of 180KW/H a month (assuming 6hrs of "good" sunlight a day for 30 days.)

      Assuming it was average output per 6 hours of usable time a day (which its probably not, its more likely the peak at the best conditions), and presuming also that surface area limits are not an issue (which they may well be), and that $1/watt was the current cost, rather than an estimate of what the technology would eventually provide, yes, $1000 would get you panels that would produce ~$180 kW-h (not kW/h) per month.
    • by Alioth ( 221270 )
      All the solar panel outputs you typically see quote peak output - i.e. with full sunshine, zero haze, with the sun shining directly onto the panel square on (rays at 90 degrees to the panel). Even a little haze (say, some high cirrus, or 7 miles visibility) typically reduces output to 70% of the peak output. A bright overcast day and you're lucky to make 20% of peak. That's with the current most efficient panel design that's easily available (monocrystalline silicon). There's no information that I've seen s
    • The cost per watt is average. But even then, this average is subjective because the amount of sunlight one gets depends on location.

      Regions near the equator would obviously harness more energy more cheaply than say the Canadian arctic where some areas get a few hours of light depending on season.

  • by Overzeetop ( 214511 ) on Friday December 21, 2007 @12:56PM (#21780562) Journal
    It's not just the cost of the panel that matters, but the anticipated life of the panel. Traditionally, it has taken more energy to make a panel than that panel will return to the grid. That's not as big a deal if you're truly off grid - say in the boonies, or in space - but it matters if you want to make it viable in a business sense. And it can't just be equal, it's got to be a significantly low fraction. Otherwise you're creating an energy storage medium (and a very limited one in the case of a solar panel) instead of a power generator.
    • by Alioth ( 221270 ) <no@spam> on Friday December 21, 2007 @01:05PM (#21780692) Journal
      The current generation solar panels have an energy payback time of 6 years in the real world, and typically last for at least 25 years.

      Presumably, what makes this technology potentially less expensive is it requires less resources to make than silicon solar cells, so it's fairly likely that they have a faster energy payback than silicon cells.
    • Re: (Score:3, Interesting)

      by matt_martin ( 159394 )
      For sure, usable life is an important part of the cost/benefit and energy balance calculation.

      However, I've seen energy payback quoted anywhere from 1-3 years for conventional silicon photo-voltaic solar panels including the glass and metal packaging. As they are supposed to have a life > 20 years I'm not sure your second statement is correct. Do you have a source ?

    • Re: (Score:3, Informative)

      Traditionally, it has taken more energy to make a panel than that panel will return to the grid.

      That's actually incorrect. The average till a couple of years ago used to be 1:4, that is, the total production energy was about 1/4 of the energy the panels would generate in their lifetime.

      But I guess mods can't be bothered to check facts.
    • Re: (Score:3, Informative)

      by steveha ( 103154 )
      Traditionally, it has taken more energy to make a panel than that panel will return

      However, that is no longer the case. I quote Wikipedia:

      In the 1990s, when silicon cells were twice as thick, efficiencies 30% lower than today and lifetimes shorter, it may well have cost more energy to make a cell than it could generate in a lifetime. The energy payback time of a modern photovoltaic module is anywhere from 1 to 20 years (usually under five)[12] depending on the type and where it is used (see net energy gain

  • Indium (Score:4, Insightful)

    by RikF ( 864471 ) on Friday December 21, 2007 @12:57PM (#21780574)
    This stuff is already hard to come by. We won't all be covering our houses in this stuff!
    • Re: (Score:3, Informative)

      by Bryansix ( 761547 )
      "It is estimated that, at current consumption rates, there is only 13 years' supply of indium left."

      This according to New Scientist which is quoted in the Wikipedia Article [] on Indium.
  • From the ebay auction:

    This solar panel is currently in Seller's possession but it will be held in escrow until 6/1/2009 before local pick-up by the winning bidder (or shipment at cost to the winning bidder).


  • This body deliberately left blank.
  • We need a good way to store electricity because solar power is intermittent. The flywheel battery [] is not yet ready for transportation applications. Not crash resistant. But for domestic and office use one can bury this 10 feet below ground to "contain" it in the event of failure. A cheap solar cell installation and a reliable storage system will take many homes to reduce their load on the grid.

    Despite all that, our transportation sector still relies too heavily on imported oil. Till we find a solution

  • Consumer use? (Score:3, Interesting)

    by Dan East ( 318230 ) on Friday December 21, 2007 @01:03PM (#21780660) Journal
    Since they are focusing on cheap manufacturing instead of light conversion efficiency, these things may not produce much output per unit of area.

    So it may be one of those scenarios where you would have to cover your entire roof, as well as those of your two nearest neighbors, to generate enough power for a single house. In other words, they may be intending this for use in solar farms out in rural areas, where real-estate is not a concern.

    Dan East
  • Beware of headlines.

    While the sun might be strong enough at some locations to provide the headline power output for the price paid, is this only going to be on the equator in high summer?

    Considering that (in most countries) more power is consumed during the winter months to keep warm, the power output from solar power is at it's lowest so more cells are needed than would be the case to generate the same amount of power during the summer. Likewise, the industrialised countries tend not to be in the areas

  • Some calculations (Score:5, Informative)

    by SamP2 ( 1097897 ) on Friday December 21, 2007 @01:09PM (#21780738)
    In hotter climates people use solar roofings already, especially for electric water boilers. But with sufficiently cheap and available coating, people could make entire roofs covered with solar panels. You'd also of course have to think about things like durability and waterproofing.

    (Up front, I apologize to all the yanks for being an insensitive clod that doesn't use imperial measurements).

    Earth's surface is absorbing ~90 petawatts of electricity any give time (Wikipedia), and with 510 million square kilometers of surface area, an incredibly rough generalized calculation says that each square meter absorbs 175 watts (this is a 24-hour average, even though obviously it's all absorbed during daytime). Of course, not all or even most of it can be converted to electricity, but still, that's a huge resource tap. I'd estimate an average home to have a roof surface area of about 50 square meters, which means that on average the sun sends 8kW on your roof. Next, the average American household uses 8900 kWh/year, which produces, again, an average usage of about 1 kilowatt per household. If you tile your entire roof with solar panels, you'd need to be able to convert 12% of heat/light energy to electricity in order to be fully self-sufficient.

    An extra bonus is that the more you absorb the sun's energy as electricity, the less of it is converted to heat which dissipates around the planet, and that in and of itself reduces the effect global warming. So you are being twice as productive - not rely on heat-trapping coal, and reduce the amount of heat that saturates on the planet in the first place.

    Of course, this would have to be done on a truly massive scale to have any effect, but every bit helps, and if the industry can make it profitable to the consumer (and of course overcome the interests of evil megalomaniac neofascistliberal Big Oil corporations, as any /. troll will point out), it'll grow on its own.
    • Re: (Score:3, Informative)

      by ZorinLynx ( 31751 )
      >the less of it is converted to heat which dissipates around the planet, and that in and of itself reduces the effect global warming.

      Allow me to teach you about the laws of thermodynamics.

      You may be converting the sunlight into electricity instead of heat directly, but unfortunately when that electricity is used, it eventually will become heat.

      It doesn't matter what you use the power for. Run a fan? The moving air will eventually slow down via friction and turn into heat. Run a light bulb? The light is e
  • CdTe vs CIGS (Score:3, Insightful)

    by savuporo ( 658486 ) on Friday December 21, 2007 @01:09PM (#21780742)
    Anyone followed First Solar ( FSLR ) IPO ?
    They were the first to bring CdTe cells to market, and guess what happened [] ..

    Now, several companies have been working furiously to get the competing CIGS cells going. Miasole, Nanosolar, HelioVolt, just to name a few. FSLR of course beat them to market, and is already a winner, but i am waiting for IPOs for the CIGS companies too ..
    Anything that doesnt use crystalline silicon is going to be huge, and in some instances, already is.
  • Honda (Score:3, Interesting)

    by Ogive17 ( 691899 ) on Friday December 21, 2007 @01:11PM (#21780772)
    Honda has been develloping CIGS technology for a few years now. I believe they are already selling these type of solar panels in Japan. []
    • You have it all wrong. Honda has never developed that kind of technology. On the other hand; Phillip Morris, Brown & Williamson, and R.J. Reynolds have not only have developed CIGS technology, but they have also been pushing CIGS on us for quite some time now. ;)
  • Corrections (Score:5, Informative)

    by abramsh ( 102178 ) on Friday December 21, 2007 @01:11PM (#21780774) Homepage
    • They are not selling at $1/watt, that is their goal. They would be selling at $2.12/watt, but they are sold out for the next 18 months.
    • They are not backed by Google, they are partially backed by some of the Google founders.

  • Watt, Watt Hour? (Score:3, Insightful)

    by WPIDalamar ( 122110 ) on Friday December 21, 2007 @01:12PM (#21780792) Homepage
    I'm confused by the $1 per watt and "cheaper than coal"...

    Please correct me if I'm wrong here, but I thought a watt was a measure of capacity whereas a watt-hour was what we actually paid for from our electric company as a measure of (what? power? energy?)... So a watt-hour is something like "continuously using one watt for one hour".

    For solar, there's no fuel cost. So the $1 gets you a "perpetual" 1 watt. If it lasted forever (which it won't), that'd be an infinite amount of watt-hours.

    But coal plants have a fuel cost. So $1 only gets them so much coal, and only so many watt-hours.

    Or is that comparing the cost of building a coal plant to building solar panels? Or is it some kind of TCO figure?

God made the integers; all else is the work of Man. -- Kronecker