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Self-Assembling Photovoltaic Cells

Posted by timothy on from the some-assembly-automatic dept.

dhj writes "MIT scientists have developed a self-assembling photovoltaic cell in a petri dish. Phospholipids (think cell membranes) form disks which act as the structural support for light responsive molecules. Carbon nanotubes help to align the disks and conduct electricity generated by the system with 40% efficiency. The assembly process is reversible using surfactants to break up the phospholipids. When filters are used to remove the surfactants the system reassembles with no loss of efficiency even over multiple assembly/disassembly cycles. The results were published September 5th in Nature Chemistry."

6 of 103 comments (clear)

  1. Like this story from before? by PCPackrat · · Score: 5, Informative

    http://science.slashdot.org/story/10/09/07/0424217/Self-Assembling-Photovoltaic-Tech-From-MIT

  2. 40%! by ebonum · · Score: 4, Informative

    One of the problems with solar that no one seems to talk about is the system is limited by the size of the southern facing roof on a house. In the case of desert power generation, a large amount of land is required. If solar cells can make the leap from 12% efficiency to 40%, this will change everything. Your roof installation will be able to produce a much more meaningful amount of power especially in the context of trying to run air conditioning during day light hours. More importantly, the same applies for many malls, warehouses, factories, etc. At 12% efficiency, the roof of a mall is simply too small to generate enough power to be off the grid during the day. The amount of land required per MegaWatt will drop considerably. At 40% efficiency solar starts to become a much more viable option.

    1. Re:40%! by sunspot42 · · Score: 4, Informative

      Nobody needs to go "off the grid" for solar to become viable. It all comes down to $ per kw/h. Even if solar can only meet 10-20% of your needs, if you can recoup your investment in a reasonable timeframe, solar is viable.

      If you live in Phoenix and have a $200 a month light bill, a hypothetical $2,500 solar array that saves you just $40 a month but which lasts for 20 years looks like a pretty good deal - it'll pay for itself 3 times over. Unlike, say, a $2,500 3D television. And of course there's the network effect - if everybody installs one of the things, demand for electricity declines by 10-20% - as does the price - meaning you could all be saving a lot more than just $40 a month. That'll also spill over into the cost you pay for locally-produced goods and services.

    2. Re:40%! by cheater512 · · Score: 4, Informative

      Actually photosynthesis tops out at 25% efficiency.
      11% using the sun's spectrum.

      It all depends on where you want to measure the efficiency.

    3. Re:40%! by Black+Gold+Alchemist · · Score: 5, Informative

      FYI, at 20 percent efficiency in California, here's the math. One watt-peak = 2 kWh/year. One house = 11040 kWh /year, thus = 5520 watts peak.
      At 1 kW/m^2 (100 percent), you get 5.5 m^2, which means 2.3 meters (7.7 feet) on a side.
      At 40 percent, you get 13.7 m^2 = 3.7 meters (12 feet) on a side.
      At 20 percent you get 27.6 m^2 = 5.5 meters (17.23 feet) on a side.
      At 10 percent you get 55.2 m^2 = 7.4 (24.3 feet) meters on a side.

      --
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      Virtue is a temptation
      Community is a cartel
    4. Re:40%! by zrbyte · · Score: 5, Informative

      40% is just the efficiency of the individual molecules in converting photons to electric charge. The overall efficiency of the device must be abysmal. The real breakthrough here lies in the fact that these guys can disassemble and reassemble the component light harvesting molecules of the device. This is important since photovoltaic devices using organic molecules are prone to degradation during irradiation by sunlight (see: http://en.wikipedia.org/wiki/Polymer_solar_cell).