Novo conceito FV, 80% eficiencia, sem concentração
Enviado: sábado ago 14, 2010 10:09 pm
vamos igualmente recapitular o que sabemos sobre as celulas fotovoltaicas classicas de silicio monocristalino ou policristalino com uma eficiençia máxima teórica de somente 20 %. não se esqueçam da aplicação inversa, tambem muito usada na nossa tecnologia, os leds (light emiting diode). mas ambas as aplicações recorrem à dopagem de semi-conductores cristalinos, o silicio. enquanto nas celulas fv convertemos luz em electricidade, nos leds convertemos electricidade em luz. esta dualidade de aplicações é encontrada nesta nova tecnologia (de 1986 !!!)
como observação final relembro que quando a luz incide sobre a matéria aquecendo-a quase na totalidade excepto a luz reflectida, enquanto numa celula fotovoltaica aquece-a com mais dificuldade pois 15 % dessa energia sai do material em forma de electricidade, mas para isolar termicamente nada como esse novo polimero que absorve 80% da energia solar recebida. estamos em todos os casos a ignorar a contribuição do ar quente pré-aquecido que circula à volta dessas celulas.
inventor: alvin marks (falecido)
data para comercialização ao publico: 2001 (ou nunca !)
tecnologia:
1. lepcon ou lumeloid (celulas fotovoltaicas)
2. elcon (celulas para iluminação)
lumeloid, classified as a polymeric photovoltaic device, is constructed from very inexpensive, non-toxic polymer materials and will be manufactured by processes in large production. finished lumeloid product will comprise a thin film about 0.3 microns thick on a low cost plastic roll. we project installed lumeloid cost at 20% that of conventional pv and lower than natural gas and coal, or about 75 cents per watt.
lumeloid does not use semiconductor principles to generate electricity, but exploits the same techniques radio antennae use to absorb radio waves; except that lumeloid absorbs nano-scale visible light waves, in a process which in part mimics photosynthesis. the linear light polarizing molecules in the film act as the antennae to absorb the energy of a resolved component of photons incident on the film.
lumeloid, classificado uma celula fotovoltaica de polimero (plasticos), é construida de polimeros não tóxicos e baratos e será (seria!) produzido por processos de manufacturação em larga escala. o lumeloid produzido consiste num filme de espessura de 0,3 microns colado sobre um rolo plastico. o custo de instalação seria 20% da instalação classiva fv e mais barata que a do gás naturale do carvão, aproximadamente 75 centimos (americanos) por watt.
o lumeloid não usa o principio dos semi-conductores para gerar electricidade, mas explora a mesma técnica que as antenas de radio usam para absorver as ondas de radio, excepto que o lumeloid absorve as ondas de luz visivel à nano-escala, num processo que copia a fotosintese. as moleculas de luz polarizada linear no filme actua como uma antena para absorver a energia dos fotões incidente nesse filme.
polaroid precursor
this cost breakthrough was instrumental in the subsequent development of polarized sunglasses and polaroid film. (in fact, marks was an early rival of dr. edwin land, developer of the land camera and founder of the polaroid corp.) in the early 1960s, marks was science advisor to the kennedy white house. today, he holds a total of 120 patents -- a number of which have application to solar power generation. marks new solar designs -- dubbed lepcon (light to electric power converter) and lumeloid -- are built on an extention of systems commonly used to receive microwave transmissions. (on the spectrum of electromagnetic energy, the difference between microwaves and visible light is merely that the latter have a higher frequency and a shorter wavelength.) microwaves -- like other radio frequency transmissions -- are best received using an antenna tuned to the wavelength of the incoming signal. (when an electromagnetic wave strikes an electrically conductive material, it induces an alternating current of the same frequency of the incoming wave.) in real-world microwave applications, the efficiency of this connversion approaches 80%. lepcon consists of millions of microscopic antennas (tuned to the wavelengths of the visible spectrum) embedded in a glass substrate. (lumeloid use less expensive plastic materials.)
a thousand points of light
with microwaves (as well as with radar and radio), however, the same tuned antenna will work as well for transmitting a signal as it does for receiving it. operate lepcon in reverse and it becomes a light source. marks calls this reverse application elcon (electricity to light converter). elcon elements in a group become a point of light, or a pixel. page 3 the same technology used to pack millions of submicron antenna elements in a glass or plastic substrate could be used to produce a new kind of high-definition tv (hdtv) screen with much higher resolution than present technology will allow. conventional u.s. tv uses 525 scanning lines of pixels per screen. the most ambitious hdtv schemes yet proposed would use something on the order of 1,250 lines per screen. using elcon technology, screens using millions of lines may be possible -- for an 80,000% increase in resolution