Today’post is by Shannon Coombs, who writes about solar technology in her own blog. She has kindly agreed to write about the latest developments in making photovoltaic more efficient. This is an important topic as photovoltaic cells need a great deal of energy to be made and if their present rates of conversion of light energy into electrical energy there will be great environmental benefits for everyone. Over to Shannon.
While silicon is the market common semiconductor in the majority of electrical units, which includes the photovoltaic cells that solar panels use to convert light into electricity, silicon is not the most cost-efficient material available. The semiconductor gallium arsenide and related substance semiconductors give practically two times the effectiveness as silicon in solar units, but they are rarely utilized in utility-scale applications mainly because of their high cost of production.
A team at the University of Illinois (http://illinois.edu/) Professors J. Rogers and X. Li has discovered cheaper ways to produce thin films of gallium arsenide. This provides a better return of electricity and allows adaptability in the types of units into which thin-film gallium arsenide can be incorporated.
Typically, gallium arsenide is placed in a single thin layer on a smaller wafer. Either the pv cell is made specifically on the wafer, or the semiconductor-coated wafer is broken up into chips. The Illinois team decided to put in several levels of the material on a single wafer, making a layered, “pancake” stack of gallium arsenide thin films.
If you increase to 10 levels in one growth, you only have to fill the wafer once. If you do this in ten growths, loading and unloading with temperature ramp-up as well as ramp-down take a lot of time. If you consider exactly what is necessary for every growth – the equipment, the preparation, the period, the workers – the overhead saving this method provides is an important expense reduction.
After that the researchers independently peeled off the layers to transport them. To achieve this, the stacks swap layers of aluminum arsenide with the gallium arsenide. Bathing the stacks in a solution of acid and an oxidizing agent dissolves the layers of aluminum arsenide, freeing the single thin sheets of gallium arsenide. A soft stamp-like system picks up the layers, one at a time from the top down, for move to one other substrate – glass, plastic material or silicon, depending on the application.
Then the wafer may be reused for one more growth.
By doing this it is possible to generate a lot more material a lot faster and much more cost effectively. This process could generate mass quantities of material, as opposed to simply the thin single-layer manner in which it is generally grown.
Freeing the material from the wafer additionally starts the probability of flexible, thin-film electronics made with gallium arsenide or different high-speed semiconductors. To make products that conform but operate at higher efficiency, is a significant breakthrough.
In a paper shared on-line May 20 in Nature (http://www.nature.com/
), the team details its procedures and shows 3 kinds of units making use of gallium arsenide chips made in multilayer stacks: light units, high-speed transistors and solar cells. The creators also provide a comprehensive price comparability, pointing out that mass production will reduce prices significantly.
One more advantage associated with the multilayer technique is the release from area constraints, especially essential for photovoltaic cells. As the levels are eliminated from the stack, they may be laid out side-by-side on an additional substrate in order to create a much larger surface area, whereas the standard single-layer process restricts area to the dimension of the wafer.
For solar panels, you want large area coverage to get as much sunlight as possible. In an extreme case we could increase enough levels to have ten times the area of the standard.
The Illinois team is researching into other semi conductor materials which might be suitable for the multilayer growth that they have demonstrated with gallium arsenide.
Shannon Combs is currently writing for the <a href=”http://www.residentialsolarpanels.org/”>residential solar power generation</a> blog, her personal hobby weblog centered on suggestions to aid home owners to create and conserve energy with sun power.
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Filed under: climate change, PV, solar, solar energy | Tagged: pv, shannon combs, thin fil solar, University of Illinois |
Robert Kyriakides's Weblog 
I still like burning stuff and making carbon dioxide for the fruit trees, melons, strawberries and corn fields. CO2 is good. It is Al Gore, Jr. that is bad. We need more CO2 not less. And, we need less government, elected people laws and regulations.
The more stuff you burn the more people you kill in the tropics.
[…] This post was mentioned on Twitter by Rasced Oley, Solar Energy. Solar Energy said: Solar Energy News: Illinois Scientists' Research will lead to Better Photovoltaic Panels http://bit.ly/9F0ouT […]
How does that happen? I seriously doubt it.
Jungle trees are slow-growing hardwoods that do little to nothing for the soil. If cut down and made into things for people, making money for locals in the process, and the field is planted in corn, it will produce 12 to 20 times as much oxygen for Earth and make corn to feed people and animals. Modern agriculture has improved everything for man and beast. There are more trees growing in North America now than when Columbus came because we know how to prevent and put out forest fires. Man has been a great boon to every living being alive, including the termite, the species with the greatest body mass of all.
I have already explained that when you clear old forests you release huge amounts of carbon dioxide into the atmosphere, from the oil and from the burning of the vegetation. Modern agriculture has fed humanity, or some of it, but at a cost.
We have hundreds or thousands of devices can be powered by solar panels, the type that can be wrapped and stored in a location which is very low. Things that can be activated as mobile phones, laptops, digital cameras, CD players, small radios and many other items. To use this type of solar panel simply unroll and place in the sun and soon begin to produce electricity. These cells are designed with the special ingredients that help to concentrate the sun’s energy. As the rays strike the earth is a special material that absorbs energy and begin the process of converting energy to electricity.
i prefer to buy those cd players with anti-shock mounts because they are much better ~;.