Jun
25
Camel Portable Solar Generator
Filed Under solar panels | 1 Comment
If you're new here, you may want to clipped from solarpowerwegrant.blogspot.com
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 clipped from www.edn.com |
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“One of the monumental health projects of our time has to be the effort to bring vaccines into remote, rural regions of the world. Vaccines must be kept cool, and in remote rural regions where it’s too darn hot to begin with, a reliable source of electricity is usually not a feature.” |
A Finnish company, NAPS Systems, addressed this need in the 1980’s with this mobile camel-solar-powered refrigerator. This version evolved into a more boring, but presumably more universal system, today’s CFS49IS.
Jun
15
To understand how photovoltaics work, you first need to understand a bit about solar energy. Basically, sunlight is loaded with photons. Think of these as little packages of solar energy. Photovoltaics are silicon panels that turn this sun power into electricity.
When the photons from sunlight hit a silicon molecule, they knock loose one of its free-floating electrons. This electron hits another silicon molecule, shunting it’s electron out of it’s molecule. This starts a chain reaction, rather like one domino striking another, which knocks over another, and another…
The final result of this chain reaction is what is known as an flow of electrons, or an electrical current.
This solar electrical current then flows through the electrical circuits of your house. It powers whatever you have on at the time lights, fridges, computers. And that’s how you turn sunlight into electricity.
Jun
11
Thin Film Photovoltaic Price
Filed Under photovoltaics | Leave a Comment
Thin Film Solar is one of the fastest growing areas in the solar panel market. This has a lot to do with the cost of thin film photovoltaic.
Thin film is cheaper than traditional silicon panels. There are several reasons for this.
One is that thin film solar cells use a lot less of the material that make makes electricity: silicon. Silicon is very abundant natural, but in its purest form, it is expensive. Thin film uses extremely thin layers of silicon, lowering the cost.
The other reason thin film photovoltaics cost less is the manufacturing process. Traditional photovoltaic require a lot of expensive manual labour. The process of applying silicon to the backing for thin film is similar to that of a printing press. This means lower labour costs and fast production.
The main disadvantage of these type of solar panels is that they are less efficient than traditional solar. This means you need more roof area to produce the same ammount of solar energy.
One innovation in this area is solar tiles. These tiles have photovoltaics in built, eliminating the need for traditional roofing. This can lower the cost of installation.
In conclusion, thin film photovoltaics have advantages in their price and their range of applications. While they are not as efficient as traditional solar panels, they are developing fast and may indeed overtake traditional silicon panels.
Jun
8
Solar Panel Efficiencies
Filed Under solar energy | Leave a Comment
I would like to about any other new progresses that have been made for cells other than the nanotechnology. Would there be any new ways of making the cells so that you can have more efficiency? People have still not figured out how to have 100% efficiency. Right?”
In Photovoltaic panels, the electricity is generated by photons (packages of sun energy) dislodging electrons held within the silicon crystalline matrix. These dislodged electrons then became a flow of electrons (electric current.)
The efficiency of these silicon panels lies in the structure of the silicon, and the way the photons interact with it.
What this means is that light energy in a photon not used in dislodging an electron is diffused as heat. This energy is not converted to electricity, and is therefore ‘wasted’ or inneficient.
The amount of energy each photon is controlled by the light wave length. For a long time, monocrystalline photovoltaics were limited by this restriction. They could only convert a fixed percentage of sunshine into electricity. Then multicrystalline solar cells were developed. These used several types of silicon in multiple layers (hence the name.)
These different layers of silicon could react to different strenths of photons, making the solar cell more efficient. The highest current efficiency is around 42% for a concentrated solar cell. This uses mirrors to concentrate sunlight onto the solar panel.
One very interesting emerging solar technologies is solar thermal. It isn’t new, and works in its simplest form by focusing sunlight with a mirror onto a pipe filled with fluid.
This fluid then heats and moves, driving a Stirling engine. Stirling engines are almost 200 year old, and very efficient if they are kept running at their optimal rate.
What makes solar thermal an exciting technology is that many companies are claiming they can produce solar thermal energy a $/watt price that is as cheap as coal.
This could be the end of the ’solar race’ that has been heralded in the solar world for the last few years. Now it looks it is finally in sight.
Jun
7
Multi-junction solar cells have cracked the 40% efficiency barrier. The structure of these cells means that they can absorb energy from a wider range of the solar spectrum.
“WASHINGTON, DC – U.S. Department of Energy (DOE) Assistant Secretary for Energy Efficiency and Renewable Energy Alexander Karsner today announced that with DOE funding, a concentrator solar cell produced by Boeing-Spectrolab has recently achieved a world-record conversion efficiency of 40.7 percent, establishing a new milestone in sunlight-to-electricity performance. This breakthrough may lead to systems with an installation cost of only $3 per watt, producing electricity at a cost of 8-10 cents per kilowatt/hour, making solar electricity a more cost-competitive and integral part of our nation’s energy mix.”
It’s important to note here that this is for a concentrating solar cell. This means solar energy is concentrated, usually by mirrors, at the solar cell. Most domestic and mainstream solar panels are not concentrating.