Sounds impressive! So what material are you using in your roll process? Do you have a web site showing these things?
Michel ----- Original Message ----- From: Michael Foster To: [email protected] Sent: Sunday, May 04, 2008 3:55 AM Subject: Re: [Vo]:Fresnel focused solar It's so much fun to hear all you folks speculate on what's happening in this particular field. First, no one or no company has "beat me to the punch" in using fresnel lenses to concentrate sunlight for a photovoltaic system. This is an old and obvious idea, newly revived because of the run up in world energy prices and the soon to be dead issue of global warming. The development of new photovoltaics of different types specifically designed for high concentration is another factor. The company I own has simply and inadvertantly become the largest and most cost effective manufacturer of fresnel lenses in the world. My manufacturing capacity for such lenses dwarfs that of the rest of the world combined. Virtually every company involved in concentrator photovoltaic schemes has contacted me about this. The conventional method of manufacturing fresnels, compression molding of polymethyl methacrylate (PMMA) is slow and far more expensive that the continuous roll method I use. Furthermore PMMA lenses have a limited life in the sun and are sensitive to humidity changes. They craze and go milky in short order. They buckle and warp and are difficult to keep at optimum focus. Other thermoplastics can be used, but the cost is even higher, the cycle times even slower, and the optical transmission not as good. Just last week, I was contacted by a consulting firm hired by a company who wants to set up large photovoltaic "farms" with the idea of generating commercial quantities of electricity. They gave broad hints about the company being financed by the recent round of venture capital (nearly $700 million) floated by Algore and his new friends. Who knows what's going on here, but their main concern was could somebody produce 20,000 square meters per month. When I told the guy who called I could do that in a few hours, he damn near had an orgasm. This idea really pencils out for the photovoltaic production of electricity on a number of counts. Primarily, the amount of expensive photovoltaic material is greatly reduced, down to about 0.1% of non-concentrated flat panels. Photovoltaics designed for high concentration are approaching 50% in conversion efficiency, a figure flat panels will probably never reach. The main feature of such systems normally pointed out as disadvantage, tracking the sun, more or less pays for itself in having more hours per day of optimum output. Even flat panels would have a higher daily output if they tracked. I have no idea if someone will step up the plate and start giving me large orders for my concentrator fresnel arrays, but I'm proud of what I've done and I hope it has some practical use. Meanwhile these things find broader application for making pretty cosmetic packages. Oh, well. M. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
