July 18 2008 / by justinelee / In association with Future Blogger.net
Category: Environment Year: General Rating: 6 Hot
Lucky for us the sun is a wonderful source of clean energy. Its rays can be harnessed and transformed into electricity using semi-conductor-based solar cells that power homes, buildings, and even transportation. Researchers have spent decades trying to refine this process.
Recently, MIT researchers have made a significant mark in this endeavor. Associate Professor Marc A. Baldo, leader of the project, and a team of four graduate students of the Department of Electrical Engineering and Computer Science, have constructed a cost-efficient solar concentrator device based on a failed 1970s model that uses glass and dye. In practical terms, the concentrator device is a high-efficiency window.
Currently, solar concentrators on the market track the sun’s rays using large mobile mirrors that are both expensive to arrange and to maintain. Furthermore, Baldo explains, the solar cells that house these concentrators must be cooled, thus the entire assembly wastes space.
Baldo’s new solar concentrator increases the amount of usable energy by a factor of 40, all while cutting costs by reducing the amount of solar cell, which because its base is silicon is rather expensive.
The device consists of glass coated with a mixture of relatively inexpensive dyes that absorbs the light and re-emits it on a new wavelength into the glass to be collected by the solar cells, which are located on the edges of the glass.
Baldo says the 1970s model failed in two ways: the collected light was absorbed before it reached the edges of the glass and the dyes were unstable.
Using optical techniques developed for lasers and other diodes, the MIT engineers found the perfect ratio of dyes that would allow the light that is absorbed and emitted to travel a longer distance before reaching the solar cells. (cont.)
The team has successfully combated previous obstacles and have created a device that they believe is highly marketable. In fact, three of the four researchers, Michael Currie, Jon Mapel, and Shalom Goffri, have co-founded Covalent Star, a company that will further commercialize the solar concentrator with hopes of production within three years.
By discovering ways to use effective materials that are easy and inexpensive to manufacture, Baldo and his team are making the future of widespread solar-powered homes a closer reality. Pretty soon average Americans who want to do their part for the environment and save some money on electricity bills will have that opportunity.
via MIT news