Solar power game-changer: "near perfect" absorption of sunlight, from all angles

// added November 06, 2008 // 22 comments //
Image...
SeaJade
There are some trade-offs but a really interesting and hopefully progressive step forward.

"A new solar panel coating developed at Rensselaer Polytechnic Institute significantly boosts absorption of different light spectrums with greater angular flexibility. (Photo: Inhabitat)
Researchers at Rensselaer Polytechnic Institute have discovered and demonstrated a new method for overcoming two major hurdles facing solar energy. By developing a new antireflective coating that boosts the amount of sunlight captured by solar panels and allows those panels to absorb the entire solar spectrum from nearly any angle, the research team has moved academia and industry closer to realizing high-efficiency, cost-effective solar power.

"To get maximum efficiency when converting solar power into electricity, you want a solar panel that can absorb nearly every single photon of light, regardless of the sun's position in the sky," said Shawn-Yu Lin, professor of physics at Rensselaer and a member of the university's Future Chips Constellation, who led the research project. "Our new antireflective coating makes this possible."

An untreated silicon solar cell only absorbs 67.4 percent of sunlight shone upon it - meaning that nearly one-third of that sunlight is reflected away and thus unharvestable. From an economic and efficiency perspective, this unharvested light is wasted potential and a major barrier hampering the proliferation and widespread adoption of solar power.

After a silicon surface was treated with Lin's new nanoengineered reflective coating, however, the material absorbed 96.21 percent of sunlight shone upon it - meaning that only 3.79 percent of the sunlight was reflected and unharvested. This huge gain in absorption was consistent across the entire spectrum of sunlight, from UV to visible light and infrared, and moves solar power a significant step forward toward economic viability.

Lin's new coating also successfully tackles the tricky challenge of angles.

Most surfaces and coatings are designed to absorb light - i.e., be antireflective - and transmit light - i.e., allow the light to pass through it - from a specific range of angles. Eyeglass lenses, for example, will absorb and transmit quite a bit of light from a light source directly in front of them, but those same lenses would absorb and transmit considerably less light if the light source were off to the side or on the wearer's periphery.

This same is true of conventional solar panels, which is why some industrial solar arrays are mechanized to slowly move throughout the day so their panels are perfectly aligned with the sun's position in the sky. Without this automated movement, the panels would not be optimally positioned and would therefore absorb less sunlight. The tradeoff for this increased efficiency, however, is the energy needed to power the automation system, the cost of upkeeping this system, and the possibility of errors or misalignment."

Monday 03 November 2008

by: Rensselaer Polytechnic Institute
  1. groups:
    News,   Green,   Science
  2. tags:
    News Green Environment Science 5 more

22 comments // Solar power game-changer: "near perfect" absorption of sunlight, from all angles

  • av8r
    • 0
      av8r  
    • no doubt im getting this for my (future) house, no matter what the cost, it means better bills and more peace of mind

    • 1 year ago
  • rasting
  • Bren589
  • thewarnerla
  • AveryMoore
    • 0
      AveryMoore  
    • PlatoTacius

      Agreed, with a proviso or two.

      It's one thing to be made a slave by compulsion. But when there is a choice, and it is far less costly to make it, then those who let themselves be the money-switch flipped by power companies are their own jailers. "Each in his prison thinking of a key, thinking of a key each assumes --- ----"

      Off Grid is the only prospect we have to end national impoverishment. Permanent servitude to folks, on shore and off, who are quite prosperous, in fact ridiculously so, already.

    • 1 year ago
  • PlatoTacius
    • 0
      PlatoTacius  
    • Avery, I agree, the only way to truly be free is to be off-grid, however, there are so many who just want to flip the switch and not have to think about whether it will work tomorrow without maintenance... there has to be a way to stop paying through the nose for utility services, but the big companies don't want that change. They are comfortable where they're at...raking in the huge profits...

      I'm exited about this development, because it greatly reduces the cost of having the mechanized system in order to achieve ultimum efficiency... We are in a good position to move forward with this technology and explore many more ways to improve our lives and wean ourselves off of Big Oil...

      Those who don't get with the program will fiind themselves behind very soon... or else they'll be the straglers clinging to petroleum dependency...

    • 1 year ago
  • ruberube
    • 0
      ruberube  
    • Nice thread. Such scientists that create inovative
      and needed products are true heroes!

      We Americans need to become more involved and write letters to congress ect. demanding such science and implementaion of diverse energies. It seems and feels we finally will have a progressive government hence we need to be active and take part!.

    • 1 year ago
  • AveryMoore
    • 0
      AveryMoore  
    • ruberube:

      Agreed 100%

      We seen for years that our politicians prefer to protect archaic tech than support innovation. If this country was Holland

      1/ regular shoes would be banned. Wooden shoes only!

      2/ There would be no dikes to protect the country from being flooded by the sea. Dikes cost money, money means paying TAXES! No one wants to pay money just to keep from drowning. Companies wouldn't invest the money for no reason. So in rolls the ocean.

      Fortunately the Dutch are smarter than to ignore risks rather than attribute greater risk to democracy and greed in overcoming major problems.

    • 1 year ago
  • aDREWh
    • 0
      aDREWh  
    • Is this the guy from Kanarka Technologies? Because if it is then the next step they will take is to make the solar panels flexable. Can we say phones that charge by themselves!

    • 1 year ago
  • bluestranger
    • 0
      bluestranger  
    • There is no doubt that the new technologies are speeding us toward a brighter. As our green technology advances, the companies should keep in mind the consumer cost. All of the technology will not serve us well unless it is affordable by the masses.

    • 1 year ago
  • bedeboop
  • bansheewail
  • bedeboop
  • the_Jack
    • 0
      the_Jack  
    • This is so exciting. I can't wait until the new-generation, super-efficient panels are available to consumers... or until industrial solar arrays using the new coating start providing cheaper, cleaner power for electrical ultility companies to sell to residential and business customers.

    • 1 year ago
  • AveryMoore
    • 0
      AveryMoore  
    • hapykap writes,

      "Discounts, Tax incentives this is the way to go to get it to everyone on the Planet - Big Blue."

      There's a miriad of methods by which we can switch from fossil fuel slavery to some other sort of voluntary serfdom - and thus continue to fall behind on the cost of merely living.

      The only strategy which makes any sense is "Off Grid." Once we disconnect from perpetual dependency on giant energy and food corporations we recover our strength, vitality and future. Otherwise it's feudalism all over again.

    • 1 year ago
  • bedeboop
    • 0
      bedeboop  
    • Oh, I have heard about this!!! It does sound promising. I'd really like to put solar power in my house somehow and I am trying to learn as much about it as I can. That and wind power too.

    • 1 year ago
  • futurehempfarmer
  • hapykap
    • 0
      hapykap  
    • Let the light shine in...

      Man is truly shedding the old and embracing his greatness.

      It has to be affordable and practical for the do-it yourselfer and the small entrepreneur.

      Discounts, Tax incentives this is the way to go to get it to everyone on the Planet - Big Blue.

      Help the Planet - plant a solar panel on your roof.

      Live Learn Love Evolve Create Greatness and give it away...

    • 1 year ago
  • justright
  • hannesc
  • deeblackangel
  • DandelionSalad
  • SeaJade
    • 0
      SeaJade  
    • Continued from above: "Lin's discovery could antiquate these automated solar arrays, as his antireflective coating absorbs sunlight evenly and equally from all angles. This means that a stationary solar panel treated with the coating would absorb 96.21 percent of sunlight no matter the position of the sun in the sky. So along with significantly better absorption of sunlight, Lin's discovery could also enable a new generation of stationary, more cost-efficient solar arrays.

      "At the beginning of the project, we asked 'would it be possible to create a single antireflective structure that can work from all angles?' Then we attacked the problem from a fundamental perspective, tested and fine-tuned our theory, and created a working device," Lin said. Rensselaer physics graduate student Mei-Ling Kuo played a key role in the investigations.

      Typical antireflective coatings are engineered to transmit light of one particular wavelength. Lin's new coating stacks seven of these layers, one on top of the other, in such a way that each layer enhances the antireflective properties of the layer below it. These additional layers also help to "bend" the flow of sunlight to an angle that augments the coating's antireflective properties. This means that each layer not only transmits sunlight, it also helps to capture any light that may have otherwise been reflected off of the layers below it.

      The seven layers, each with a height of 50 nanometers to 100 nanometers, are made up of silicon dioxide and titanium dioxide nanorods positioned at an oblique angle - each layer looks and functions similar to a dense forest where sunlight is "captured" between the trees. The nanorods were attached to a silicon substrate via chemical vapor disposition, and Lin said the new coating can be affixed to nearly any photovoltaic materials for use in solar cells, including III-V multi-junction and cadmium telluride.

      Along with Lin and Kuo, co-authors of the paper include E. Fred Schubert, Wellfleet Senior Constellation Professor of Future Chips at Rensselaer; Research Assistant Professor Jong Kyu Kim; physics graduate student David Poxson; and electrical engineering graduate student Frank Mont.

      Funding for the project was provided by the U.S. Department of Energy's Office of Basic Energy Sciences, as well as the U.S. Air Force Office of Scientific Research."

    • 1 year ago

Add your comment

current videos