There’s been a recent and cool new breakthrough in solar power technology. Scientists at NREL have developed a way to use chemicals in order to etch a trillion microscopic holes in silicon wafers. So what does this mean for the solar industry? Actually it might mean quite a bit especially in solar power costs.
The scientists start with a cylindrical wafer of silicon and introduce chloroauric acid which creates nano-particles of gold that then etch into the silicon in such small diameter that it would take 40 of these holes to equal one human hair.
Light comes from the sun as protons and then can be converted into electrons for our use. The problem lies in the fact that the protons bounce off of surfaces and the potential energy is then lost. This is where the tiny little holes come in. Through the addition of these holes being etched into the gray silicon it turns incredibly black which will allow the silicon wafer to capture all the colors of light the sun throws at it.
Now black silicon wet etch technology is not perfect yet, and there are still a lot of studies to do. For one the wafer itself is able to capture more protons then traditional PV reflective surfaces. However NREL’s solar cells made with the solar wafer are still a few tenths of a percentage less efficient then traditional photo voltaic cells. NREL is now working on improving the effiency of the solar wafer.
But with this technology the cost of producing solar cells is greatly reduced, and simplified using the chemical bath, and forgoing a reflective surface. They have also found that the solar wafer requires about a third less of the energy as opposed to adding a reflective layer. Furthermore the solar wafer is much better for the environment as dangerous gases are used in the production of traditional solar cells such as silane, and nitrogen trifluoride. These gases are horrendous to the environment, and therefore cuts down on greatly on greenhouse gases. This will mean a significant drop in the cost for solar roof tiles and other photo voltaic devices.
Visit http://www.renewableenergyworld.com/rea/news/article/2010/09/cheaper-better-solar-cell-is-full-of-holes to read the full story.