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Advantages of Solar Modules( Solar Panels)

Solar panels are clean - while generating electricity from sunlight, solar panels produce virtually no pollution, whereas burning fossil fuels releases large quantities of toxic gases into the atmosphere.

For the consumer, solar panels can free the individual from reliance on the power grid and the monopolistic energy supplier. Once you make the initial investment in hardware, you will have free electricity for years to come.      
Fossil Fuels are limited - Although fossil fuel reserves are expected to run dry within the next century, solar power is clean, abundant, and will remain a renewable resource that can meet all of Earth's energy needs for billions of years to come.      
Types of Solar Cells

There are several types of solar cells and these are each divided into subcategories. The basic types of solar cells sold on the market are as follows:

Single crystal silicon solar cells have been the most widely used. They are also the most expensive form of solar cell and are largely responsible for solar energy's reputation as costly.      
Polycrystalline solar cells are cheaper than single crystal silicon solar cells but not as effective in energy conversion.      
Thin film technology has the distinct advantage of being easier to mass produce than crystal cell technology. It costs less, though its durability is questionable. Thin film is also less efficient than crystal silicon, according to most sources.      
About Solar Modules      
Solar modules (also called solar panels ) are made up of solar photovoltaic cells. A solar cell is vaguely circular, two to three inches in diameter and organized in rows and columns on a solar panel. For example, a 150-watt solar panel is often four rows by nine columns of solar cells.      
Solar modules use arrays of solar cells to convert photons into usable electricity. With solar panels, we are provided with clean, renewable energy from the sun.      
Solar panels are typically constructed with cystalline silicon, which is used in other industries (such as the microprocessor industry), and the more expensive gallium arsenide, which is produced exclusively for use in photovoltaic (solar) cells.      
Other, more efficient solar panels are assembled by depositing amorphous silicon alloy in a continuous roll-to-roll process. The solar cells created from this process are called Amorphous Silicon Solar Cells, or A-si. Solar Panels constructed using amorphous silicon technology are more durable, efficient, and thinner than their crystalline counterparts.      
For very important solar projects, such as space probes that have to rely on solar energy, very-high efficiency solar cells are constructed from gallium arsenide by a process called molecular beam epitaxy. Solar cells constructed by this process have several p-n junction diodes, each designed to be maximally efficient at absorbing a given part of the solar spectrum. This solar panels are much more efficient than conventional types, but the process and materials involved make them far too expensive for everyday applications.      
The newest solar panels function on the molecular or quantum level, and represent an exciting new technology coming into play. These solar panels are created by implanting carbon nanotubes or quantum dots into a treated plastic. Unlike silicon-based solar panels, these solar panels do not have to be constructed in a clean room, and therefore production costs are somewhat dimished      
How Solar Modules Convert Sunlight into Electricity

Solar panels collect solar radiation from the sun and actively convert that energy to electricity. Solar panels are comprised of several individual solar cells. These solar cells function similarly to large semiconductors and utilize a large-area p-n junction diode. When the solar cells are exposed to sunlight, the p-n junction diodes convert the energy from sunlight into usable electrical energy. The energy generated from photons striking the surface of the solar panel allows electrons to be knocked out of their orbits and released, and electric fields in the solar cells pull these free electrons in a directional current, from which metal contacts in the solar cell can generate electricity. The more solar cells in a solar panel and the higher the quality of the solar cells, the more total electrical output the solar panel can produce. The conversion of sunlight to usable electrical energy has been dubbed the Photovoltaic Effect.

The photovoltaic effect arises from the properties of the p-n junction diode, as such there are no moving parts in a solar panel.      
How Much Power do Solar Modules Produce?      
In direct sunlight at the surface of the equator, a maximally efficient photovoltaic cell about 1/5m in diameter creates a current of approximately 2 amps at 2 volts, however, due to the Earth's atmospheric interference, terran solar panels will never perform as well as solar panels exposed directly to the sun's rays.      
Years of overheating and physical wear can, however, reduce the operation efficiency of the photovoltaic unit. Solar cells become less efficient over time, and excess energy is released into its thermally conductive substrate as infrared heat.      
The amount of power solar panels produce is influenced by the quality of the solar panel, the materials and technology used in making the solar panel, and the amount of time the solar panel has been in use. When purchasing solar panels, it is therefore wise to look beyond size and look at the dollars/watt ratio.      
Solar Insolation and Solar Panel Efficiency      
Solar Insolation is a measure of how much solar radiation a given solar panel or surface recieves. The greater the insolation, the more solar energy can be converted to electricity by the solar panel. Click to learn more about solar insolation.      
Other factors that affect the output of solar panels are weather conditions, shade caused by obstructions to direct sunlight, and the angle and position at which the solar panel is installed. Solar panels function the best when placed in direct sunlight, away from obstructions that might cast shade, and in areas with high regional solar insolation ratings.      
Solar panel efficiency can be optimized by using dynamic mounts that follow the position of the sun in the sky and rotate the solar panel to get the maximum amount of direct exposure during the day as possible.      
Crystalline Silicon Solar Panel      
The creation of solar panels typically involves cutting crystalline silicon into tiny disks less than a centimeter thick. These thin, wafer-like disks are then carefully polished and treated to repair and gloss any damage from the slicing process. After polishing, dopants (materials added to alter an electrical charge in a semiconductor or photovoltaic solar cell) and metal conductors are spread across each disk. The conductors are aligned in a thin, grid-like matrix on the top of the solar panel, and are spread in a flat, thin sheet on the side facing the earth.   Photovoltaic Solar Panels  
To protect the solar panels after processing, a thin layer of cover glass is then bonded to the top of the photovoltaic cell. After the bonding of protective glass, the nearly-finished panel is attached to a subtrate by an expensive, thermally conductive cement. The thermally conductive property of the cement keep the solar panel from becoming overheated; any leftover energy that the solar panel is unable to convert to electricity would otherwise overheat the unit and reduce the efficiency of the solar cells..      
Despite these protective measures against the tendancy of solar panels to overheat, it is vital that when installing a solar panel, additional steps should be taken to ensure the solar panel is kept cool. Elevating the solar panel above ground to let the airflow underneath cool the device.      
Amorphous Silicon Solar Panel      
Amorphous silicon solar panels are a powerful, emerging line of photovoltaics, that differ in output, structure, and manufacture than traditional photovoltaics which use crystalline silicon. Amorphous silicon solar cells, or A-si cells, are developed in a continuous roll-to-roll process by vapor-depositing silicon alloys in multiple layers, with each extremely thin layer specializing in the absorption of different parts of the solar spectrum. The result is record-breaking efficiency and reduced materials cost (A-si solar cells are typically thinner than their crystalline counterparts).      
Some Amorphous Solar Panels also come with shade-resistant technology or multiple circuits within the cells, so that if an entire row of cells is subject to complete shading, the circuit won't be completely broken and some output can still be gained.      
The development process of Amorphous Silicon solar panels also renders them much less susceptible to breakage during transport or installation. This can help reduce the risk of damaging your significant investment in a photovoltaic system.      
Factors of Solar Module Costs      
Solar panels of the same size may produce variable amounts of electricity - this discrepancy arises from variations in the functioning age of the solar cells, the quality of the solar cells, and with what technology they were produced. Early solar cells, for example, are not quite as efficient as modern solar cells, so you'll find that with a trusted solar panel manufacturer, quality increases as the technology involved becomes more advanced and precise.      
Solar panels have an effective lifespan of about 20 to 25 years, and their value and wattage output decrease steadily over time. Quality, age, and technology all play a role in the cost of the solar cell.      
The best way to compare the value of two solar cells is to measure the dollars/watt ratio. The current best deals on solar cells is about $4.30 per watt. For a 50 watt solar panel, your total cost will be about $215.      
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