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Power Hardware Technology

Stanford's New Solar Tech Harnesses Heat, Light 117

An anonymous reader writes with this excerpt from a Stanford news release: "Stanford engineers have figured out how to simultaneously use the light and heat of the sun to generate electricity in a way that could make solar power production more than twice as efficient as existing methods and potentially cheap enough to compete with oil. Unlike photovoltaic technology currently used in solar panels — which becomes less efficient as the temperature rises — the new process excels at higher temperatures. ... 'This is really a conceptual breakthrough, a new energy conversion process, not just a new material or a slightly different tweak,' said Nick Melosh, an assistant professor of materials science and engineering, who led the research group. 'It is actually something fundamentally different about how you can harvest energy.' And the materials needed to build a device to make the process work are cheap and easily available, meaning the power that comes from it will be affordable." The abstract for the researchers' paper is available at Nature.
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Stanford's New Solar Tech Harnesses Heat, Light

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  • by Anonymous Coward on Monday August 02, 2010 @03:16PM (#33114240)

    What a coincidence, I just happen to have a chart for the last ten to fifteen years here:

    http://thephoenixsun.com/archives/10688

  • by mark-t ( 151149 ) <markt AT nerdflat DOT com> on Monday August 02, 2010 @03:19PM (#33114278) Journal
    I get the impression from the article that this tech would be impractical outside of situations where parabolic mirrors are not being used to focus the sun's energy onto such a solar cell. That makes it mostly impractical for everyday use.
  • by TooMuchToDo ( 882796 ) on Monday August 02, 2010 @03:20PM (#33114298)
  • by dch24 ( 904899 ) on Monday August 02, 2010 @03:20PM (#33114300) Journal

    Can anyone point me to a good cost/watt chart over time? I would love to be able to see how prices have dropped over the past two decades. I keep hearing that solar has to drop in price... but have no baseline to judge our progress.

    It depends on what you want: space solar panels are the most expensive multi-junction technology, but achieve the highest efficiency.

    If you're a huge company, you can get really great deals because you purchase whole manufacturing runs. This is also why it's hard for an individual to buy direct from any manufacturer: all their production capacity is probably already bought up by large companies, so you get the "seconds," the panels that those resellers decide they would like to sell to you (at a price mark up, of course).

    Here are some panel price charts, though they're not perfect:

    http://www.solarbuzz.com/Moduleprices.htm [solarbuzz.com]
    http://futurist.typepad.com/my_weblog/2007/08/solar-energy-co.html [typepad.com]

    But I should point out the bias on these sites: they're in the industry, not independent review sites. So they will be competing to drive your dollars to their products.

  • by joggle ( 594025 ) on Monday August 02, 2010 @03:35PM (#33114448) Homepage Journal

    Continue reading:

    Melosh calculates the PETE process can get to 50 percent efficiency or more under solar concentration, but if combined with a thermal conversion cycle, could reach 55 or even 60 percent – almost triple the efficiency of existing systems.

  • by tgd ( 2822 ) on Monday August 02, 2010 @03:43PM (#33114528)

    Actually lots of it has. PV arrays are far more efficient now than even ten years ago, and the technologies around heat-based concentrators is also far advanced. There are parts of the country where its affordable to run a house entirely off solar -- something not possible a decade ago.

    Just because the whole world hasn't converted doesn't mean the innovations aren't making it to the market, it just means even doubling efficiency hasn't helped make it cheaper than oil.

  • by jellomizer ( 103300 ) on Monday August 02, 2010 @03:44PM (#33114538)

    There is a big gap between lab results and making a product out of it.

    1. There is the price to produce.
    2. Are the materials robust enough for real life.
    3. Is the research funded by an organization who will actually give it to industry. Oddly enough there are some groups who are so Anti-Business after there research is done they don't want to sell it to a big company as they would be selling out.
    4. Can the technology be reproducible.
    5. Is it safe.

    There are a lot of details to be worked out.

  • by Tumbleweed ( 3706 ) * on Monday August 02, 2010 @03:52PM (#33114634)

    And in eastern Canada, hydro-electricity is generating above 80% of our needs, even generating electricity for the north-eastern USA states in some cases.

    Here in Seattle, we're at almost 89% via hydro, nuclear at over 5.6%, and wind at over 3.4%. We're like at 2% or so (at least as of 2008) for coal & natural gas combined; that's well beyond what even I had thought for our area.

  • by Anonymous Coward on Monday August 02, 2010 @03:54PM (#33114680)

    They aren't the only ones working on this process, I know a few others. Also, thermal and PV processes have been combined successfully before, unlike the claim in TFA - my own work centers on CPVT (Concentrating PV/Thermal) collectors. You can reach 40-50% efficiency like that. (Hell, you can get close to 30% just with triple-junction PV).

    Look for papers by Abraham Kribus if you're into it.

  • Sadly, uneconomic (Score:4, Informative)

    by Kupfernigk ( 1190345 ) on Monday August 02, 2010 @04:07PM (#33114838)
    Thermoelectric looks obvious, doesn't it? A few years ago I thought how convenient it would be to use the waste heat from my Diesel boat heater to generate electric power, and I contacted a manufacturer. The reply I got was "we're not even going to quote you because it's insanely expensive". Apparently thermoelectric generators are so expensive they only make sense on things like trans-Siberian or Alaskan gas pipeline monitors, where there isn't enough light for a solar PV supply and the cost of miles of environmentally resistant wiring would be even more prohibitive. Although Peltier generators are cheap, they are hugely inefficient - and even more inefficient in reverse. It would have been cheaper to cover the entire deck in solar panels.
  • Re:Sadly, uneconomic (Score:1, Informative)

    by Anonymous Coward on Monday August 02, 2010 @04:37PM (#33115296)

    You're absolutely right, current thermoelectric power sucks. Photon enhanced thermionic emission is much, much, much more efficient than seebeck effect conversion (which is what you mean when you say peltier).

  • by buback ( 144189 ) on Monday August 02, 2010 @04:52PM (#33115560)

    Solar array costs per watt have dropped considerably, but an array still costs an arm and a leg.

    here are some reasons:
    - Enough batteries to keep your freezer frozen through the night and maybe a couple cloudy days is expensive.
    - Labor costs of installation are 25-50% of installation costs, but if you don't get it installed and inspected by the proper people, your home owners insurance will probably be canceled.
    - It's very expensive to install enough panels to power multiple computers, multiple TV's, ACs, Fridges, Microwaves, and a multitude of other electronic devices. Customers need to reduce their power consumption before investing in a solar array.
    - Tying your solar array into the grid is expensive. you can't just dump power into the grid. it has to be clean and in phase with grid power, and has to be installed by a certified electrician. (btw it's not just THE grid, it's the power companies grid. They tell you when you can use it. If the power goes down in your neighborhood they will turn off your inverter, because they need the lines powered down when the linemen are working on them.)

    Labor costs are not going to go down drastically, so i don't know how much cheaper it can get to the end user. in addition, it seems that as panel costs go down, Inverters are getting more user-friendly, and hence more complex and expensive. inverters alone run from $5000 to $8000 these days.

  • by thorpie ( 656838 ) on Monday August 02, 2010 @04:57PM (#33115638)
    The progress report from March 2010, available at http://gcep.stanford.edu/research/factsheets/petesolor_results.html [stanford.edu], provides a more detailed and understandable summary of what they are doing
  • Re:Sadly, uneconomic (Score:2, Informative)

    by ohiovr ( 1859814 ) on Monday August 02, 2010 @05:23PM (#33116070)
    Johnson Thermo-Electrochemical Converter System isn't a peltier type device. An excerpt from the link: "The JTEC is an all solid-state engine that operates on the Ericsson cycle. Equivalent to Carnot, the Ericsson cycle offers the maximum theoretical efficiency available from an engine operating between two temperatures" Carnot like efficiency is pretty amazing for a solid state device. Hell for any device... Of course, even though it may be more efficient, it doesn't automatically make it more economical.
  • by pspahn ( 1175617 ) on Monday August 02, 2010 @05:41PM (#33116328)

    What, you thought that each of these announcements about laboratory successes would instantly result in a new product on the shelf of your local Wal-Mart?

    Seeing as they expected someone else to go gather all the data proposed, I would say yes.

  • by budgenator ( 254554 ) on Monday August 02, 2010 @05:48PM (#33116450) Journal

    Not necessarily, parabolic trough [wikipedia.org] concentrators aren't that exotic, there are many DIY [youtube.com] examples on youtube.

  • by Colin Smith ( 2679 ) on Monday August 02, 2010 @07:51PM (#33117878)

    Somewhere around 60% of our electricity usage is simply moving heat around. Either producing it where it's cold or removing it when it's hot. There are far more efficient and cheaper ways to do this.

    http://www.eia.doe.gov/emeu/reps/enduse/er01_us.html [doe.gov]

    Stop the heat moving; insulate everything. Internal and external walls. Roofs, floors, refrigerators/freezers. If not vacuum panels, research into the production of really cheap aerogels for building, DIY materials and domestic devices would probably do more to reduce electricity usage and bills than solar panels.

     

  • More likne (Score:1, Informative)

    by Anonymous Coward on Monday August 02, 2010 @08:19PM (#33118092)

    To correct the gp : In the Quebec province (Eastern Canada) as of 2008 : 95.6% of electricity is from hydroelectric sources.... and climbing. (Source Wikipedia)

  • Ask Me Anything (Score:3, Informative)

    by danriley ( 1869432 ) <danriley@stanford.edu> on Tuesday August 03, 2010 @01:11AM (#33119948)
    Hi all. I'm one of the researchers on the project. As they say on Reddit, Ask Me Anything. I'll do my best to answer everyone's questions.

An authority is a person who can tell you more about something than you really care to know.

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