Solar cells and the environment impact

Well, once you start looking at the options with solar energy things look pretty rosy right? I mean in ten years from now a third of the produced energy will be solar or otherwise green ( wind power, biomass… ). Most building will be energy self suficient with those fancy dyes on every window and spray-on solar cells everywhere. Right? Well not quite. Everything looks fine until you realize that to produce solar cells NF3 is used. NF3 or nitrogen trifluoride is a gas thats used in the production of LCD displays and solar cells. Unfortunately it is also a very potent green house gas.

Fortunately The Linde Group a world leading producer of gasses has found out that NF3 can be replaced with fluorine gas. Fluorine has no effect on the green house effect and its readily available. On top of that it also speeds the production process thus lowering the costs of solar cells altogether.

For the in detail story click below:

http://www.marketwatch.com/news/story/making-lcd-tv-solar-cell/story.aspx?guid={96198A7A-9B93-43DF-BF35-D7C74148E3F5}&dist=hppr

 

Solar thermal – solar at night!

One of the big problems of solar energy has always been availability. There’s no sun on a cloudy day or at night. The solution would be to store the suns energy and use it when the sun is not available. Storing elecrticity in such quantities is very expensive. Another solution would be to use the electricity to produce hydrogen that can be latter used to produce electricity again. This process is not very efficient and storing hydrogen is both expensive and dangerous.

The proposed solution is to store heat which is both cheap and effective. The accumulated heat can later be used to produce electricity when it is needed.

The system uses an array of mirrors that reflect the sun’s heat onto a tank of water. The produced steam turns a turbine. Really simple – a good old fasioned steam engine. This works even at night because water can store heat for a long time.

 

Windows as solar panels

A new invention that would allow domestic window to function as solar panels was recently invented by scientist at MIT in Boston. The real invention is a special coat that aplied to the windows conducts some of the light to the edges where the solar cells are. This has several advantages it allows for smaller solar cells lowering the cost of the installations, concentrates the light raising the eficiency as the solar cells are more eficient at higher light intensities. Another major saving is the unobtrusive installation that requires just a coat of the revolutionary material thus eliminating the need of expensive roof mounted panels or concentrators that need further cooling.

 

Spray on Solar Cell

One of the breakthroughs in the field came in late 2005 with the invention of a plastic solar cell that can be sprayed on other materials to form a very versatile source of energy. One can envision the material being sprayed on cell phones, laptops, cars … giving the devices true independence from wires and recharging. Larger scale implementations could be the use of the spray to cover entire buildings or even unused land such as deserts to provide an abundant green source of renewable energy.

Scientists are expecting to improve on the efficiency of the plastic cells by harnessing the infrared part of the sun’s light, which represents about 50% of the total light that reaches the earth and which other solar cells cannot use to produce electricity.  Another benefit of this aspect is the possibility to use the cells in cloudy weather or even at night in warm climates as infrared light is actually heat.

With greater efficiency come lower costs. Solar power is infact 3-5 times more expensive than the average U.S. residential power costs. The spray on power cells may finaly brige this gap and bring solar power to the mainstream.