Posted on 03/01/2006 5:25:16 AM PST by Mikey_1962
Energy security has become one of the hottest political topics in the last few years with the prospects of skyrocketing oil prices and shortages. Along with the looming dangers of climate change, the urgency of alternatives to CO2 emitting energy sources is becoming more obvious by the day. One of the most important actions to counter these challenges is the establishment of alternative energy sources such as solar energy. Latest research by South African scientists have taken us one step further to realising these goals.
Solar power has traditionally been differentiated into solar thermal and solar photovoltaic systems. The photo-voltaic effect is a phenomenon that depends on quantum physics, and allows specific materials to directly convert solar radiation to electricity. The photo-voltaic effect is used in solar panels, that have been powering spacecraft for decades and have recently been making their presence felt in supplying electricity to free-standing locations on earth, like telephone towers and pump systems on farms.
However, the panels available commercially today are almost all based on high-purity silicon as the photo-voltaic material, and these panels are much more expensive than the equivalent amount of coal, petrol or gas.
The only way to make photovoltaic energy more widely used, is to make devices (including solar panels) that are much cheaper than the current silicon-based devices. The most promising PV material identified to date is Copper-Indium-Gallium-Diselenide (CIGS).
CIGS is much more efficient than silicon at converting incident sunlight into an electric current: Less than one micron of CIGS absorbs more than 99% of available incident solar energy, compared to 350 microns of silicon to do the same job.
Despite the excitement around CIGS, significant cost savings compared to silicon were not achieved, despite 20 years of research. However, a new development has made the picture considerably brighter.
(Excerpt) Read more at scienceinafrica.co.za ...
Work done over the last two years indicates that panels can be produced in commercial volumes at a cost of about R 500 for a 50 Watt panel. This is much cheaper than existing solar panels available on the market. CIGS is a remarkably stable material and conversion efficiencies should be sustainable for 15-20 years in any given panel.
RAU physicists are currently collaborating with physicists from the University of Port Elizabeth and the University of Pretoria to make 20 Watt CIGS panels, thanks to an award by the Innovation Fund in the national Department of Science and Technology during 2003. The award, in the amount of R 13,2 million, has been used to construct a pilot assembly facility on the RAU campus (with more than R 2 million of top-up funds added by RAU management).
The two main components of the facility are a state-of-the-art sputtering instrument and a state-of-the-art diffusion oven. The former was designed by Leybold Optics of Dresden, Germany, and the latter by Wilro Technologies in the Netherlands. Both these instruments were designed according to Prof Alberts' unique and novel specifications and are, at the moment, the only examples of their kind in the world. They also constitute the best combination of instruments of this kind in the world at present.
Benefits This patented technology has caused great excitement across a broad front of stakeholders, since it promises to bring the practical cost of applying solar photovoltaic systems for electricity production down to a level comparable to coal-fired or nuclear technologies.
Furthermore, the technology contributes nothing to carbon dioxide emissions and consumes only the resources used to manufacture the solar panels (the metals copper, indium and gallium and the non-metal selenium). These materials could in principle all be recycled into new panels at the end of the useful lifetime of a panel, since no material whatsoever is consumed. The finite lifetime (15-20 years) of a panel is simply due to deterioration of the crystal structure over time.
The energy used to make a panel is recovered within 1-2 years of operation, beyond which a further 13-18 years of net energy production remain. There is no vulnerability to disruptions in fuel supply, since sunlight is the fuel consumed.
In addition, solar photovoltaic technology can be produced in any desired amount, from a few milliwatts to many megawatts, if so desired. It is not necessary to erect large power stations to serve a community with energy from this technology.
A typical middle-class suburban family needs only about 30 square metres (about the size of a living room) of solar panels to supply all of its electricity needs.
The technology also holds great promise for socio-economic development, especially in the rural areas of Southern Africa. - RAU
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"A typical middle-class suburban family needs only about 30 square metres (about the size of a living room) of solar panels to supply all of its electricity needs
If this turns out to be true and it pays for itself in 1 to 2 years as claimed, where do I sign up?"
DITTO!!!
If I kept copies of all the stories about novel new materials that will finally make solar economic, I'd have a stack as tall as me.
Solar probably isn't the best option for those of us in the not so sunny north but every little bit helps. I've got lots of solar charged outdoor lights around that yard and haven't been disappointed.
What does race have anything to do with this subject????
I'm unsure why it matters, but Vivian Alberts is white.
Really? Why's that? This is great news about CIGS, but what's urgent about anthropogenic CO2 emissions?
Is this a typical middle class family in the U.S. or in South Africa, where the article and research originate?
If "R" means South African Rands, then R500 ~= $31, which is indeed a price breakthrough. The current going rate for a finished 50W panel is just over $200. Wow!
Recently I was in California and I saw an entire development being constructed that was using solar slates on the roof. The roofs were very attractive and looked exactly like roof slate. I understand it powers the entire house.
Oops, I did that math wrong. 1R = $0.16, so R500 would be about $83 not $31.
I guess banned8 is keeping a track of this due to the pro-black racism and affirmative action/quota hiring that some have reported in SA.
If a predominantly black team had created this stuff then it would be great news - a sign that talent rises to the top even in a (reportedly) discriminatory environment.
Check this out!!
George Washington Carver was a fine example of the cream rising to the top even against the odds.
Sounds great; life off the grid as much as possible is a GOOD thing!
I still think the most promise lies in concentraing the light and heat from the sun in a large satellite-dish type device and using it to turn a Stirling engine to power a generator or charge a deep-cell battery. The loss of efficiency is far less than the conversion of light.
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