“Greenhouse Gas” Technology Goes to Work for Low-Cost Solar Power System

December 9th, 2011 by Tina Casey

A team of researchers at the Massachusetts Institute of Technology has come up with a way to lower the cost of solar energy, by mimicking the same effect that enables greenhouse gases to trap heat in the Earth’s atmosphere. The new technology could eventually lead to powerful concentrated solar energy systems that don’t rely on the huge arrays of mirrors that are required in conventional systems.

Making More Solar Power without Mirrors

Instead of using mirrors, the MIT researchers fabricated a crystalline material arrayed with precisely spaced microscopic holes. Sunlight can enter the holes, but most of the radiation can’t find its way out by the same route. That’s because holes are configured in such a way that the rays must reflect back at precisely the right angle in order to escape. Think of a high-tech lobster trap of nanoscale proportions, and you’re on the right track. David L. Chandler of MIT News compares this approach to the greenhouse effect, in which radiation from the sun is admitted to the Earth’s atmosphere and is trapped there.

Many Routes to Low-Cost Solar Power

According to Chandler, the new material – called photonic crystal – could be manufactured using standard processes that are used to fabricate chips. That could give the new device a cost advantage over mirror-based technologies, which require precise optics to boost efficiency. The idea is that simplicity of manufacturing plays a key role in determining the installed cost of solar power, an approach that President Obama’s SunShot solar power initiative aims to encourage.

No Last Hurrah for Mirrors in Solar Energy

Despite the potential of the new technology, mirrors will most likely remain an important part of the low-cost solar toolkit. Another team at MIT, for example, is developing a low-cost concentrated solar system that positions mirrors on a hillside to focus sunlight downwards. That reduces the amount of pumps, piping and other complexities of conventional systems that aim

sunlight upwards, at a tower. As for optics, the aluminum giant Alcoa is working on concentrated solar systems using low-cost mirrors made of – what else – aluminum, with comes with the advantage that most of the installation could be easily recycled when it’s time for replacement.

Image: Greenhouse effect. Some rights reserved by Global Jet.

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Tags: Alcoa solar power, Concentrated Solar Power, greenhouse gas effect, low cost solar power, MIT solar research, photonic chips, SunShot Initiative

About the Author

Tina Casey Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.

http://pulse.yahoo.com/_J3I4DHPNRLC4WCAYI6T5LFEZ4U The Dunner

That is so amazing! That kind of technology is mind blowing to me. It gives radiation and sunlight a persona or even character,. Thank you MIT and keep up the good work.
Tom G.

Leave it to MIT to keep the stream of ideas and innovation coming. When solar cost less than $1.00/watt and is 40% efficient, we won’t need anything else except some efficient way to store the energy. That will be a day we can all cheer.

When do you think we will hit those numbers? In 5 year, 10 years or maybe never?
- Anonymous
  
  40% efficient and <$1/watt is a long way off.
  
  <$1/watt for panels is already here. Now the task is to bring down installation costs.
  
  We've got lots of rooftops, parking lots, brownfields, landfills and other good places to install panels. More efficiency would be great, it would greatly help bring down installation costs but we should not let that get in our way.
  
  Solar has now reached grid parity. It brings no hidden costs that makes the cost of power much higher than what we pay at the meter. Let's just get a bunch installed and cut what we pay for electricity.

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