How is pv cells made

Shunt resistance must then be tested using partially shaded junctions. An important test of solar modules involves providing test cells with conditions and intensity of light that they will encounter under normal conditions and then checking to see that they perform well. The cells are also exposed to heat and cold and tested against vibration, twisting, and hail.

The final test for solar modules is field site testing, in which finished modules are placed where they will actually be used. This provides the researcher with the best data for determining the efficiency of a solar cell under ambient conditions and the solar cell's effective lifetime, the most important factors of all.

Considering the present state of relatively expensive, inefficient solar cells, the future can only improve. Some experts predict it will be a billion-dollar industry by the year This prediction is supported by evidence of more rooftop photovoltaic systems being developed in such countries as Japan, Germany, and Italy.

Plans to begin the manufacture of solar cells have been established in Mexico and China. Likewise, Egypt, Botswana, and the Philippines all three assisted by American companies are building plants that will manufacture solar cells. Most current research aims for reducing solar cell cost or increasing efficiency. Innovations in solar cell technology include developing and manufacturing cheaper alternatives to the expensive crystalline silicon cells.

These alternatives include solar windows that mimic photosynthesis, and smaller cells made from tiny, amorphous silicon balls. Already, amorphous silicon and polycrystalline silicon are gaining popularity at the expense of single crystal silicon.

Additional innovations including minimizing shade and focusing sunlight through prismatic lenses. This involves layers of different materials notably, gallium arsenide and silicon that absorb light at different frequencies, thereby increasing the amount of sunlight effectively used for electricity production. A few experts foresee the adaptation of hybrid houses; that is, houses that utilize solar water heaters, passive solar heating, and solar cells for reduced energy needs.

Another view concerns the space shuttle placing more and more solar arrays into orbit, a solar power satellite that beams power to Earth solar array farms, and even a space colony that will manufacture solar arrays to be used on Earth. Bullock, Charles E. Monegon, Ltd. Komp, Richard J. Practical Photovoltaics. Aatec Publications, Making and Using Electricity from the Sun.

Tab Books, Crawford, Mark. March 23, , pp. May 19, , pp. Edelson, Edward. June, , p. Murray, Charles J. March 11, , p. Toggle navigation. After the initial purification, the silicon is further refined in a floating zone process. In this process, a silicon rod is passed through a heated zone several times, which serves to 'drag" the impurities toward one end of the rod.

The impure end can then be removed. Next, a silicon seed crystal is put into a Czochralski growth apparatus, where it is dipped into melted polycrystalline silicon. The seed crystal rotates as it is withdrawn, forming a cylindrical ingot of very pure silicon. Wafers are then sliced out of the ingot. This illustration shows the makeup of a typical solar cell. The cells are encapsulated in ethylene vinyl acetate and placed in a metal frame that has a mylar backsheet and glass cover.

Periodicals Crawford, Mark. The first 2 kinds of cells have a somewhat similar manufacturing process. Read below about the steps of producing a crystalline solar panel.

It all starts with the raw material, which in our case is sand. Most solar panels are made of silicon , which is the main component in natural beach sand. Silicon is abundantly available, making it the second most available element on Earth. However, converting sand into high grade silicon comes at a high cost and is an energy intensive process.

High-purity silicon is produced from quartz sand in an arc furnace at very high temperatures. The silicon is collected, usually in the form of solid rocks. Hundreds of these rocks are being melted together at very high temperatures in order to form ingots in the shape of a cylinder. To reach the desired shape, a steel, cylindrical furnace is used.

In the process of melting, attention is given so that all atoms are perfectly aligned in the desired structure and orientation. Boron is added to the process, which will give the silicone positive electrical polarity. Mono crystalline cells are manufactured from a single crystal of silicon. Mono Silicon has higher efficiency in converting solar energy into electricity, therefore the price of monocrystalline panels is higher.

Polysilicone cells are made from melting several silicon crystals together. You can recognise them by the shattered glass look given by the different silicon crystals. After the ingot has cooled down, grinding and polishing are being performed, leaving the ingot with flat sides. Wafers represent the next step in the manufacturing process.

The silicon ingot is sliced into thin disks, also called wafers. A wire saw is used for precision cutting. The thinness of the wafer is similar to that of a piece of paper. Because pure silicon is shiny, it can reflect the sunlight. To reduce the amount of sunlight lost, an anti-reflective coating is put on the silicon wafer. The following processes will convert a wafer into a solar cell capable of converting solar power into electricity. Each of the wafers is being treated and metal conductors are added on each surface.

The conductors give the wafer a grid-like matrix on the surface. This will ensure the conversion of solar energy into electricity.

The coating will facilitate the absorption of sunlight, rather than reflecting it. In an oven-like chamber, phosphorous is being diffused in a thin layer over the surface of the wafers. This will charge the surface with a negative electrical orientation.

The combination of boron and phosphorous will give the positive - negative junction, which is critical for the proper function of the PV cell.

The solar cells are soldered together, using metal connectors to link the cells. Solar panels are made of solar cells integrated together in a matrix-like structure. The current standard offering in the market are:.

The most common sized system in terms of kWh for UK homes is the 4kWh solar system. After the cells are put together, a thin layer about mm of glass is added on the front side, facing the sun. The backsheet is made from highly durable, polymer-based material.

This will prevent water, soil, and other materials from entering the panel from the back. An aluminized conductive material is deposited on the back positive surface of each cell, restoring the P-type properties of the back surface by displacing the diffused phosphorus layer.

Each cell is then electrically tested, sorted based on current output, and electrically connected to other cells to form cell circuits for assembly in PV modules. For more information about FSEC, please contact us or learn more about us. Find us on Facebook!