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Facts About Solar Energy
The sun has been around for about 4.5 billion years and is expected to be around for another 4-5 billion years. The output of solar energy that the sun delivers to earth is absolutely enormous. Theoretically, if we could harness the energy from one hour of sunlight from around the world, it could provide the energy needs for the entire world’s population for a year! Further, it should also be noted that only about 50% of the sun’s energy actually reaches the surface of the earth. In addition to being abundant, solar energy is both clean and renewable and available almost anywhere on our planet.
The challenge is not the supply of solar energy but rather the ingenuity of man in harnessing and applying it economically. Solar energy has been and continues to be used to provide electricity, heating, cooling, lighting, communications, transportation and as well as being incorporated into many other devices and appliances.
There are basically three ways solar energy is harnessed. They are:
• Photovoltaic This is the process of converting sunlight to electricity. This process is commonly identified with the use of solar cells or panels. This method is commonly used in solar lighting
• Concentrating Solar Power (“CSP”) Is a utility-scale application where sunlight is concentrated primarily through a wide grid of collection mirrors to heat a liquid or solid to produce steam to drive generators to produce electricity.
• Solar Thermal Hot Water, Heating and Cooling Similar to the CSP method previously discussed, rather than the sun generated heat going to drive generators the heated liquid or solid is interfaced with coils for heating or cooling.
Solar energy can also be categorized into two other categories. The categories are (1) active solar and (2) passive solar.
• Active solar involve the conversion of the sun’s heat into another form of energy through mechanical means. An example is the conversion via mechanical turbines to electric power.
• Passive solar provides heat when the environment is cool and cooling when the environment is warm but not by mechanical means. This is accomplished “passively” through building materials, design, window and floor selection.
Lastly, the good news is that the solar market continues to grow while the technological cost associated with this growth is coming down. In 2010, the solar energy market was the fastest growing US energy segment in the attaining a 67% growth rate. Market share grew from $3.6 Billion in 2009 to $6.0 Billion in 2010 due to federal tax credits and the ever lowering technological costs. The increase in capacity was enough to power an additional 200,000 homes and also resulted in the doubling of the use of solar panels.