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Solar Energy Basics

We have used the Sun for drying clothes and food for thousands of years, but only recently have we been able to use it for generating power.The Sun is 150 million kilometres away, and amazingly powerful.

Just the tiny fraction of the Sun’s energy that hits the Earth (around a hundredth of a millionth of a percent) is enough to meet all our power needs many times over.

In fact, every minute, enough energy arrives at the Earth to meet our demands for a whole year – if only we could harness it properly.

Solar Energy Basics

Solar is the Latin word for sun—a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That’s because more energy from the sun falls on the earth in one hour than is used by everyone in the world in one year. A variety of technologies convert sunlight to usable energy for buildings. The most commonly used solar technologies for homes and businesses are solar water heating, passive solar design for space heating and cooling, and solar photovoltaics for electricity.

Businesses and industry also use these technologies to diversify their energy sources, improve efficiency, and save money. Solar photovoltaic and concentrating solar power technologies are also being used by developers and utilities to produce electricity on a massive scale to power cities and small towns.

The energy from the sun can be used to overcome the energy crisis generated by the scarcity of resources like oil and gas. Solar energy is free and it is everywhere. That is why now more and more countries have switched to processes which help them conserve the heat and light from sun.

Access of Sun to Earth

Sun is a part of solar system and it completes its rotation around the earth in 365 days. When the sunrays travel a long way from sky to earth they carry with them the heat and light of sun. Our earth is capable of absorbing this heat. 30% of the solar energy is sent back while the remaining 70% is consumed by the oceans, rivers, land and clouds. This solar energy is also responsible for rain. It is this energy which completes the water cycle for us. The water vapors accumulate in the air and when they are carried to some higher altitude, these vapors compress themselves to clouds and they shower rain. We receive 3, 85,000EJ energy every year which is sufficient to meet the energy requirement of solar projects. It is not the sun which is responsible for global warming it is the industry and businesses run by man who is responsible. The widespread devastation of forests for bio fuels has affected the mechanism of greenhouse effect hence there is now more heat in summer than which can be tolerated.

Uses & Applications of Solar Energy

The development and research in the field of alternative fuel generation has also given rise to improvement in the utilization of solar energy. The various applications of solar energy include solar power houses, solar vehicles, cooking, water purification, solar lighting and use of solar thermal energy. The most recent progress in the field of solar energy consumption is the introduction of the concept solar thermal energy. This is the way to harness solar rays to generate heat from them. This process is used to heat water using evacuated tube collectors and glazed flat plate collectors. Thermal solar energy is also used to disinfect water form the germs using sunrays. The heat from the sunrays eliminates the bacteria present in the tap water; this process is called water treatment. Solar energy is also used to cook food in solar cookers. These cookers are specifically designed to store heat of sun to utilize later on. Another amazing dimension of solar heating is the “Process Heat”. Parabolic dish antennas and scheffler reflectors facilitate this process and the heat stored in this way is used for industrial applications. This process is not only helpful in generating electricity but it also produces steam. Some other applications include solar ponds and solar power houses.

Electricity Generation from Sunlight

Electricity today has become essential for our survival. However with the passage of time the cost of production and consumption has also increased. This has forced mankind to look for the alternative ways to generate electric current. The heat from the sun is converted to electricity using Photovoltaic. The use of Photovoltaic was limited to very small applications like solar calculators. However now this mechanisms is used to generate electricity in very large power houses of up to 14MW. This is an economical way to produce electricity however every solar power house requires a strong backup support usually form wind power houses. However for the purpose of using Photovoltaic at home one can maintain a backup system by using batteries.

How Solar Power Works or How Solar Energy Works

The light and heat generated by sun can be conserved for diverse energy and power applications. Solar energy source of energy is under the phase of development and experimentation. Solar energy valuable energy is capable of providing heating, ventilation and fuel alternatives. Sun is an abundant energy resource and most of all it comes with the environment friendly package. Hence it is a common thought now that this energy source would lead towards its way to the end of this century.

Chemical Reaction in the Sun

The sun is the ruling star in of our solar system. This useful star provides us comfort, energy and growth. It is the presence of sunlight that we are able to grow plants and cultivate our barren land. Hydrogen consumed during nuclear fusion present in the sun generates radiant energy. This process helps the solar rays to reach earth in the form of very small energy packets called photons. These photons are absorbed by our oceans and land. When the sunrays reach to earth they interact with the oceans and rivers. The heats present in the sunlight facilitate the process of evaporation. It is in this process that water vapors, winds and cyclones are produced. If we implant aerodynamic wind mills in the way we can generate electricity from this process as well.

Solar Energy Working

If we store sunlight for constant 20 days we can replace a yearly reserve of coal, natural gas and oil. The energy present in the earth’s outer atmosphere is about 1300 Watts, which reduces to 1000Watts when it finally reaches the earth. The solar energy works only if we store it. Solar energy collectors are now implanted to store this energy. These are large flat black containers which are covered by glass. These solar energy collectors are placed ate the roof tops or in large barren land which is specifically allocated to solar energy consumption. The collector contains pipes which carry liquid in them. The liquid is a mixture of alcohol and water. This process either heats the water or air (the air is carried through the radiators to the building).the working of solar energy is also dependent upon how we utilize and transform it.

Conversion of Solar Energy

The solar energy is converted to chemical energy when plants use it to perform the process of photosynthesis. Hence solar energy works by utilizing its light and heat effectiveness. The solar energy is converted into thermal solar energy by directly converting the heat from the sun into thermal energy. When the power of the sunrays is converted into the electricity with the help of chemical reaction in the solar cells, it is an example of Photovoltaic conversion of energy. It is important to understand here that solar energy works naturally to facilitate the growth of plant and the working of our echo system. However now there are many artificial ways to make use of the solar energy. This solar energy works for us humans if we store it using different storage devices like the panels, solar cells and scheffler reflectors. Simple examples of solar cooker will explain how this solar energy works? Solar cooker is comprised of metal foil. This metal foil is capable of storing heat. When we place this solar cooker under sun for an entire day .it stores enough heat in it for the purpose of cooking food later in the evening. These solar cookers were invented to prevent immense deforestation in the rural areas. These cookers are an inexpensive and environment friendly way to cook food. The reason for environment friendliness is that these cookers do not generate harmful gases like carbon monoxide.

Why We Prefer Solar Energy, Reasons to Use Solar Energy

If we observe our environment which is the most abundant and free resource available to us, the answer is solar energy. Hence it is a natural alternative to fossil fuels like oil, gas and coal. The energy from the fossil fuels and water is used to generate electricity at large. The scarcity and wastage of these resources have made them expensive to use. Therefore solar energy is the low cost and safe alternative to the other fuels. There are many reasons to use solar energy like expensive fossils and bio fuels, global warming and development in solar energy utilization.

Expensive Bio Fuels

Solar energy is a renewable energy source which is relatively inexpensive. The reason for its being getting famous is its availability and abundance. While in the case of other bio fuels like oil and gas which are limited to the ownership of few countries this natural resource is free. These countries have monopoly over these resources and it is over their will that the prices of these biofuel like coal and oil fluctuate in the international market. Hence if we work on developing solar energy power plants we can save sufficient amount of tax imposed on importing oil and other biofuels. Development of power house using bio fuels is also an expensive project. All one need is to deploy solar grids. However the solar power project requires minimum initial investment. The deployment of solar grids is scaleable because the more you deploy solar grids the more you produce electricity.

Global Warming and Solar Energy

The use of fuels like oil and gas in homes, cars and industry has brought us to the problem of global warming. The extreme production of harmful gases like carbon monoxide has destroyed the ozone layer hence we receive both the harmful and harmless sunrays. The extreme pollution in our planet has disturbed the smooth working of our echo system. This has resulted in lower rainfalls and dries whether. The use of sun to support industrial processes can help us overcome the worst situation of global warming. It can also help us stop destroying our fertile land from the harmful waste resulting from industrial processes. The governments all over the world are supporting the solar power projects especially in the under developed countries. The south Asian countries like Pakistan, India and Bangladesh are planning major solar power projects to utilize the beneficial solar energy.

Development and Research in the field of Alternative Fuels

The research in the field of alternative fuels has helped scientist to discover renewable energy projects. One such solar project which was initiated in the red sea recently was the experiment of solar ponds. The red is rich in salt content. It is deep and contains heaps of salt. This presence of salt is utilized to store solar heat in it. The temperature in lower salt layers reaches to 90 degrees Celsius which is sufficient to process heat and water. Such developments and more in this field are economical this is another reason why we should switch to alternative energy sources. The solar energy is helpful in generating tax free electricity at home that is why now end users have deployed batteries which support solar electricity generation. Solar energy is of many uses like water treatments, cooking and ventilation. The awareness about using solar cookers in rural areas has also helped to decrease the cut down of trees for cooking purposes. The solar vehicles do not emit harmful gases like other vehicles. hence all in all the profusion and simplicity to use the solar energy has gave us innumerable reasons to use it as a renewable energy source alone or in combination with wind and geothermal energy sources.