May 25, 2008
Home Brew Solar Power
How I built an electricity producing Solar Panel
"Several years ago I bought some remote property in Arizona. I am an astronomer and wanted a place to practice my hobby far away from the sky-wrecking light pollution found near cities of any real size. I found a great piece of property. The problem is, it's so remote that there is no electric service available. That's not really a problem. No electricity equals no light pollution. However, it would be nice to have at least a little electricity, since so much of life in the 21st century is dependant on it.
I built a wind turbine to provide some power on the remote property. It works great, when the wind blows. However, I wanted more power, and more dependable power. The wind seems to blow all the time on my property, except when I really need it too. I do get well over 300 sunny days a year on the property though, so solar power seems like the obvious choice to supplement the wind turbine. Solar panels are very expensive though. So I decided to try my hand at building my own. I used common tools and inexpensive and easy to acquire materials to produce a solar panel that rivals commercial panels in power production, but completely blows them away in price. Read on for step by step instructions on how I did it. "
Posted by Sun at 08:11 AM | Comments (0)
May 09, 2008
Photosynthetic dimmer switch
Berkeley researchers identify photosynthetic dimmer switch
In a study of the molecular mechanisms by which plants protect themselves from oxidation damage should they absorb too much sunlight during photosynthesis, a team of researchers has discovered a molecular "dimmer switch" that helps control the flow of solar energy moving through the system of light harvesting proteins. This discovery holds important implications for the future design of artificial photosynthesis systems that could provide the world with a sustainable and secure source of energy.
The pigment-binding protein CP29, one of the "minor" light-harvesting proteins in green plants, has been identified as a valve that permits or blocks the critical release of excess solar energy during photosynthesis. Furthermore, it has been proposed that the opening and closing of this valve can be controlled by raising or lowering ambient pH levels.
Posted by Sun at 03:26 PM | Comments (0)
April 01, 2008
Print Solar Cells With an Inkjet Printer
Print Solar Cells With an Inkjet Printer
If you like the idea of solar power, but aren't convinced by expensive, clunky solar panels just yet, here's a more manageable option: print your own on an inkjet! Konarka Technologies has just debuted a printable solar panel film that uses a common inkjet printing process to manufacture paper-thin photovoltaic solar cells. Using the existing and very simple technologies of your office inkjet printer, Konarka has essentially replaced ink with the solar cell material, and paper with a thin flexible sheet of plastic.
HERE'S HOW IT WORKS:
Essentially, the head of an inkjet printer deposits a material (ink) into a substrate (paper), and does so in a fairly cheap and quick manner. Konarka's technique uses the solar cell material as ink, and a thin flexible plastic as paper. According to the company, the process creates solar cells which are almost as good as the clunky silicon ones, created with much more advanced technologies. However, these inkjet babies are much much cheaper.
"Demonstrating the use of inkjet printing technology as a fabrication tool for highly efficient solar cells and sensors with small area requirements is a major milestone," stated Rick Hess, president and CEO at Konarka.
Unfortunately we probably won't be seeing the Inkjet-solar-panel option flying off the shelves of Office Depot just yet, as it is currently only feasible for large productions of solar cells. However, it does mean that if the uptake of this technology happens relatively quickly, you will be seeing solar cells of different sizes and price-points appearing everywhere soon.
Posted by Sun at 10:24 PM | Comments (0)
More-Powerful Solar Cells
Technology Review: More-Powerful Solar Cells
1366 Technologies claims that it improves the efficiency--a measure of the electricity generated from a given amount of light--of multicrystalline silicon solar cells by 27 percent compared with conventional ones. The company's efficiency and cost claims are based on results from small solar cells (about two centimeters across) made in the lab of Emanuel Sachs, a professor of mechanical engineering at MIT, who is one of the company's founders. 1366 Technologies is building a pilot-scale manufacturing plant that will make full-sized solar cells (about 15 centimeters across). Within a year, the company will decide whether its pilot-plant results justify building a factory for commercial production, Sachs says.
Commercial solar cells made from multicrystalline silicon are normally far less efficient than more expensive ones made from single-crystal silicon, but they're cheaper. The 27 percent improvement will bring multicrystalline cells to efficiencies about the same as single-crystal cells--around 19.5 percent--at the lower costs. So, if the technology successfully scales up, Sachs says, it could significantly bring down the cost of solar electricity. Sachs says that today, solar cells cost about $2.10 per watt generated. When manufactured at a commercial scale, the first cells incorporating his new technology will cost $1.65 per watt. Planned improvements will bring down this cost to about $1.30 a watt, he says. To compete with coal, the cost will need to come down to about $1 a watt, something that Sachs predicts can be achieved by 2012 with further improvements in antireflection coatings and other anticipated advances.
The company's first prototype solar cells include three key innovations to improve efficiency. The first is a method for adding texture to the surface of the cells that allows the silicon to absorb more light, a trick that's been used before with single-crystalline devices but has been difficult to implement with multicrystalline silicon. The rough surface causes light to bend as it enters the cell so that when it encounters the back of the cell, it doesn't reflect right back out; rather, it bounces off at a low angle and remains inside the slab of silicon. The longer the light remains within the silicon, the greater the chance that it will be absorbed and converted into electricity.
Posted by Sun at 10:20 PM | Comments (0)
March 16, 2008
Cheaper, Robust Solar Cells
Technology Review: Toward Cheaper, Robust Solar Cells
Cheap and easy-to-make dye-sensitized solar cells are still in the early stages of commercial production. Meanwhile, their inventor, Michael Gratzel, is working on more advanced versions of them. In a paper published in the online edition of Angewandte Chemie, Gratzel, a chemistry professor at the �cole Polytechnique F�d�rale de Lausanne in Switzerland, presents a version of dye-sensitized cells that could be more robust and even cheaper to make than current versions.
Dye-sensitized solar cells consist of titanium oxide nanocrystals that are coated with light-absorbing dye molecules and immersed in an electrolyte solution, which is sandwiched between two glass plates or embedded in plastic. Light striking the dye frees electrons and creates "holes"--the areas of positive charge that result when electrons are lost. The semiconducting titanium dioxide particles collect the electrons and transfer them to an external circuit, producing an electric current.
These solar cells are cheaper to make than conventional silicon photovoltaic panels. In principle, they could be used to make power-generating windows and building facades, and they could even be incorporated into clothing. (See "Window Power" and "Solar Cells for Cheap.") A Lowell, MA-based company called Konarka is manufacturing dye-sensitized solar cells in a limited quantity. But the technology still has room for improvement.
Posted by Sun at 05:21 AM | Comments (0)
February 27, 2008
How to make a solar power generator
"How to make a solar power generator"
Using parts easily available from your local stores, you can make a small solar power generator for $250 to $300. Great for power failures and life outside the power grid. Power your computer, modem, vcr, tv, cameras, lights, or DC appliances anywhere you go. Use in cabins, boats, tents, archaeological digs, or while travelling throughout the third world. Have one in the office store room in case of power failures in your highrise. I keep mine in my bedroom where it powers my cd player, turntable, lights, modem, laptop, and (ahem) a back massager. I run a line out the window to an 8" x 24" panel on the roof.
Posted by Sun at 01:55 AM | Comments (0)
January 13, 2008
Solar Homes are for economists
Solar Homes Aren't Just for TreeHuggers : TreeHugger
Last year we noted that solar panels do not a green house make. Nevertheless, we are delighted to see that property developers who are not necessarily selling overtly ‘green houses’, are still seeing the value of adding solar – in the same way as the might add central air, or walk-in closets. Lennar Homes, for example, will be installing solar panels on 100% of new homes in the San Francisco Bay area, a step that will ...
Posted by Sun at 05:34 PM | Comments (0)
January 12, 2008
Solarsiedlung by Rolf Disch
Greenline Solarsiedlung by Rolf Disch
"Maximizing the use of solar energy and minimizing heat loss" - Rolf Disch
The Solarsiedlung or "solar village" is Europe's most modern solar housing project. Solarsiedlung is the housing portion of a larger development which also includes an office/housing block called Sonnenschiff (solarship). The project's goals are to follow both the German Passive House and Plus Energy House directives as well as show good stewardship of the environment through material selection, appliance choice, energy consumption, transportation options, and construction method. By being part of the Plus Energy House initiative, each house can be referred to as a power station.
Posted by Sun at 08:53 PM | Comments (0)
Rolf Disch's Heliotrop House
Rolf Disch's Heliotrop House : TreeHugger
Our head is spinning from all the rotating buildings. Architect Rolf Disch built his own home as a test bed for solar systems. The house tracks the sun, so that its triple-glazed front can face the warming sun in winter and show its well insulated back in summer. The balcony rail is a solar vacuum tube to heat water. Photovoltaics on the roof rotate independently to track the sun, generating four to six times the energy needed for the house, making it beyond zero energy and into "das Plusenergiehaus" or a "Plus-energy House." If that is not enough, there is on-site composting, chemical free sewage treatment and rainwater catchment.
Posted by Sun at 08:51 PM | Comments (0)
January 10, 2008
New nanostructured thin film shows promise for efficient solar energy conversion
New nanostructured thin film shows promise for efficient solar energy conversion
In the race to make solar cells cheaper and more efficient, many researchers and start-up companies are betting on new designs that exploit nanostructures--materials engineered on the scale of a billionth of a meter. Using nanotechnology, researchers can experiment with and control how a material generates, captures, transports, and stores free electrons--properties that are important for the conversion of sunlight into electricity.
Posted by Sun at 07:14 AM | Comments (0)
Solar cells can take the heat
Solar cells have attracted global attention as one of the cornerstones of alternative energy. In theory, it seems to make abundant sense to tap into the energy of the sun to convert light to electricity with little or no emission of noxious pollutants. However, in practical terms, progress has been slow because of technological impediments and the many different factors that need to be optimized to obtain stable and high-efficiency devices. Dye-sensitized solar cells based on dye molecules adsorbed onto titanium dioxide electrodes have emerged as one of the most attractive solar-cell constructs, combining low cost and relative ease of fabrication with high-efficiency performance. Indeed, state-of-the-art solar cells with this architecture show greater than 11% light-conversion efficiency. However, the catch is that these high-efficiency solar cells typically use volatile organic solvents as electrolytes, which essentially precludes their use in outdoor applications because of the high vapor pressure of the solvents. Solvent-free solar cells fabricated so far show poor performance owing to the high viscosity of the alternative electrolytes. Now, a team of researchers at the Ecole Polytechnique Federale de Lausanne in Switzerland have fabricated a solvent-free dye-sensitized solar cell based on a binary ionic liquid electrolyte. These devices show a light-conversion efficiency of 7.6% under simulated sunlight conditions, which sets a new record for a solvent-free device.
Posted by Sun at 07:04 AM | Comments (0)
July 20, 2007
New Flexible Plastic Solar Panels Are Inexpensive And Easy To Make
ScienceDaily: New Flexible Plastic Solar Panels Are Inexpensive And Easy To Make
Researchers at New Jersey Institute of Technology (NJIT) have developed an inexpensive solar cell that can be painted or printed on flexible plastic sheets. "The process is simple," said lead researcher and author Somenath Mitra, PhD, professor and acting chair of NJIT's Department of Chemistry and Environmental Sciences. "Someday homeowners will even be able to print sheets of these solar cells with inexpensive home-based inkjet printers. Consumers can then slap the finished product on a wall, roof or billboard to create their own power stations."
"Developing organic solar cells from polymers is cheap," said Mitra. "We foresee a great deal of interest in our work because solar cells can be inexpensively printed or simply painted on exterior building walls and/or roof tops. Imagine some day driving in your hybrid car with a solar panel painted on the roof, which is producing electricity to drive the engine. The opportunities are endless. "
The science goes something like this. When sunlight falls on an organic solar cell, the energy generates positive and negative charges. If the charges can be separated and sent to different electrodes, then a current flows. If not, the energy is wasted. Link cells electronically and the cells form what is called a panel, like the ones currently seen on most rooftops. The size of both the cell and panels vary. Cells can range from 1 millimeter to several feet; panels have no size limits.
Posted by Sun at 12:27 PM | Comments (0)
June 15, 2007
Sunslates
Sunslates™ allow the roof of your home to serve as both a roof and a power plant simultaneously. A typical installation of 216 Sunslates™ (about 300 square feet / 28 square meters) will cover from 60 to 80% of your power needs, depending on location. The roof is installed by your by an Atlantis certified installer possibly with your local roofer and the electrical work is done by your local electrician.
Posted by Sun at 03:06 PM | Comments (0)