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PostHeaderIcon How do Solar Panels Work

Solar panel is a device used to convert solar energy into other forms , such as light energy and heat energy. In this article, we will try to find out the answer of the question…”How do Solar panels work?”

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Solar panel is a term used to describe the devices used for the conversion of solar energy in to other forms of energy like electrical or heat or light. This can be broadly studied under three categories.

1. Panels used to generate electricity

2. Panels used to generate heat

3. Panels used to heat water in homes.

How do solar panels work is nothing but knowing how the above panels work.

Panels used to generate electricity

Solar cells are common examples in this category of electricity generation. They are also known as photovoltaic cells. A combination of individual PV cells forms the Photovoltaic module. A collection of photovoltaic modules, which are tied together with a wire and are so designed to install it in a field readily, is known as photovoltaic panels or simply solar panels. The installation includes the photovoltaic modules, an inverter, a battery all linked to each other with a wire. Depending upon the no of cells and their arrangement there are three types of modules in this viz., crystalline silicon modules, rigid thin-film modules and Flexible thin-film modules.

Panels used to generate heat

The heat in the sun light is collected in this type of panels. They are called Solar thermal collectors. They are specially made to absorb the sunlight to provide the heat. It may appear that they are simple solar hot water panels but in reality they are more complex installations.

Though heat is generated out of sun light in these models, the heat energy is ultimately converted into other type of energy mostly electrical energy as in the case of solar power plants. The heat produced in the solar power plants is used to heat water, which in turn produce stream. A turbine connected to an electrical generator is made to drive for producing electricity.

There are three types of thermal collectors namely; solar parabolic, solar trough and solar towers which are mainly used in solar power plants. In domestic and light industry applications, flat plate and box type panels are used. Apart from that, some more types like evacuated tube, pool or unglazed, air and parabolic dish are some of the other types of panels used. Some advantages of this type of solar panels are getting high temperature enough to generate electricity, higher efficiency of these panels and wide area coverage with the use of inexpensive mirrors

Panels used to heat water in homes

In solar hot water panels, sunlight is used to heat a fluid, which is then transferred to a heat storage vessel. Heating of potable water in the sun light and storing is in hot water tank is a common example of this. How solar panel works is explained below:

Flat absorber plates are placed on the top roofs of the buildings usually residential buildings. These absorbers are coated with darks selective surface which converts the sun’s radiation into heat. The heat so produced is carried by the fluid in the tubes attached to the absorbers. The heat is taken away and stored or used. In the process the fluid gets heated up. To take away its heat and for reuse, the fluid is directed to a heat exchanger, where it gives off its heat and the cooled fluid is reused.

A mechanical pump can be used for circulating the fluid by means of a solar cell. Alternatively the principle of thermo siphon which works on convection can be used to circulate the fluid by mounting the storage vessel higher in the circuit.

How solar panel works lies in the effective use of active solar or passive solar technologies or solar combisystem. While in active solar technology electrical or mechanical devices such as pumps are used, passive solar technology does not employ any other source of energy. Solar combisystem uses the auxiliary non-solar heat source.

Solar panels are mainly used to exploit the potential of solar energy, which is rampant is availability and is cheap to use as no money need to be paid by anybody for the use of sunlight.

In the depleting conventional energy source day by day, solar energy is the right substitute for that. But, for that, we need to be cautious in keeping our environment and thereby the atmosphere clean and un-spoilt. Because, the role of atmosphere in the use of solar energy is that of a filter.

It eliminates certain harmful gases and materials from the sunlight before it reaches the earth’s surface. It acts as a checkpoint. If that is damaged the entire earth will be damaged. Global dimming, global warming etc., are some of the phrases coined by the environmental conscious people to warn the adverse effects of our atmosphere getting into nowadays. Let us be more conscious in not polluting our atmosphere so that not only we, the future generation is also able to derive the advantages of solar energy.

By Jayashree Pakhare
Published: 7/31/2007

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PostHeaderIcon Use Solar Power to Save on Electricity Bills

How does solar power work and how can it save money plus why is everyone using solar.

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Once a distant technology that just sat on roofs that a few green minded people used, solar power has become a trendy tool we can hold in our hands. Sunlight – solar energy – can be used to generate electricity, provide hot water, and to heat, cool, and light buildings.

A typical solar system will reduce the need for conventional water heating by about two-thirds. Often the plumbing from a solar heater connects to a houses existing water heater, which stays inactive as long as the water coming in is hot or hotter than the temperature setting on the indoor water heater. When it falls below this temperature, the homes water heater can kick in to make up the difference. Incorporating passive solar designs can reduce heating bills by as much as 50 percent. High-temperature solar water heaters can provide energy-efficient hot water and hot water heat for large commercial and industrial facilities.

Many large commercial buildings can use solar collectors to provide more than just hot water. Solar process heating systems can be used to heat these buildings. A solar ventilation system can be used in cold climates to preheat air as it enters a building. And the heat from a solar collector can even be used to provide energy for cooling a building. The Co-operative Insurance Building in Manchester has the largest commercial solar system in the UK. I think it looks very futuristic and cool!

You can generate electricity for a single building like the co-op but there is the potential in the future to generate enough power for a power plant. The author of a recent Christian Aid report, John McGhie, said that for $50bn (26bn) the whole of sub-Saharan Africa could be turned into a solar-generated economy. And $50bn is exactly the same amount as the continent would have to pay on extra fuel bills from oil,” he said.

Electrical retailer Currys is about to add a new item to its usual array of washing machines and other white goods – solar panels. Currys is taking a risk as the solar panels will cost far more than anything else the store sells. They say it will cost the average three bedroom household about 9,000 to buy and install solar panels – compared to 16,000 in specialist stores. There are also grants available through the Low Carbon Buildings Programme.

What other solar gadgets can you buy?

Well, Sharp, the world’s number one solar cell producer, has just turned its hand to glass studded with LED lights and cells. Instead of generating enough electricity to run a home, it creates a psychedelic light show at night, powered entirely by the day’s sun.

You can also buy solar chargers for iPods and phones. Other recent outlandish additions include a solar-powered tent, scooter and LED house numbers, while mundane ones like bike lights, torches and radios have been around for years.

People can also use captured passive solar heat to cook food. A basic cooker consists of an insulated box with a glass top. Heat from concentrated sunlight gets trapped in the box and can be used to heat food enclosed in the box. These have not been very popular to date.

By
Mark Marris
Published: 10/27/2006

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