ABOUT SOLAR POWER
Hi Friends, This article is exclusively contributed for Robotics India blog by Ms. Barbara Young who is doing a great job with her personal hobby website http://www.12voltsolarpanels.net/. Her work is dedicated to helping people save energy using solar powered energy to eliminate CO2 emissions and energy dependency.
Here's a simple option to understand how solar panels work.
What's solar power?
Solar energy is radiant energy that is produced by the sun. Every day the sun radiates, or sends out, an immense amount of energy. The sun radiates more energy in a second than people have used since the beginning of time!
The energy of the Sun derives from within the sun itself. Like other stars, the sun is known as a big ball of gases––mostly hydrogen and helium atoms.
The hydrogen atoms in the sun's core combine to form helium and generate energy in a process called nuclear fusion.
During nuclear fusion, the sun's extremely high pressure and temperature cause hydrogen atoms to come apart and their nuclei (the central cores of the atoms) to fuse or combine. Four hydrogen nuclei fuse to become one helium atom. However the helium atom contains less mass compared to four hydrogen atoms that fused. Some matter is lost during nuclear fusion. The lost matter is emitted into space as radiant energy.
It takes many years for the energy in the sun's core to make its way to the solar surface, and then slightly over eight minutes to travel the 93 million miles to earth. The solar energy travels to the earth at a speed of 186,000 miles per second, the velocity of light.
Simply a small percentage of the power radiated by the sun into space strikes the earth, one part in two billion. Yet this quantity of energy is enormous. Every single day enough energy strikes the United States to provide the nation's energy needs for one and a half years!
Where does all this energy go?
About 15 percent of the sun's energy which hits the planet earth is reflected back to space. Another 30 percent is used to evaporate water, which, lifted in to the atmosphere, produces rainfall. Solar power is also absorbed by plants, the land, and the oceans. The remaining could be used to supply our energy needs.
Who invented solar technology?
People have harnessed solar technology for centuries. As early as the 7th century B.C., people used simple magnifying glasses to concentrate the light of the sun into beams so hot they would cause wood to catch fire. Over a century ago in France, a scientist used heat from a solar collector to create steam to drive a steam engine. At first of this century, scientists and engineers began researching ways to use solar power in earnest. One important development was obviously a remarkably efficient solar boiler invented by Charles Greeley Abbott, an American astrophysicist, in 1936.
The solar hot water heater gained popularity at this time in Florida, California, and the Southwest. The industry started in the early 1920s and was in full swing just before the Second World War. This growth lasted until the mid-1950s when low-cost natural gas had become the primary fuel for heating American homes.
People and world governments remained largely indifferent to the possibilities of solar energy prior to the oil shortages of the1970s. Today, people use solar power to heat buildings and water and also to generate electricity.
How we use solar power today?
Solar energy is used in a number of different ways, of course. There are two simple forms of solar energy:
* Solar thermal energy collects the sun's warmth through 1 of 2 means: in water or in an anti-freeze (glycol) mixture.
* Solar photovoltaic energy converts the sun's radiation to usable electricity.
Listed here are the five most practical and popular solutions solar energy is used:
1. Small portable solar photovoltaic systems. We see these used everywhere, from calculators to solar garden tools. Portable units can be utilized for everything from RV appliances while single panel systems can be used traffic signs and remote monitoring stations.
2. Solar pool heating. Running water in direct circulation systems via a solar collector is a very practical method to heat water for your pool or hot spa.
3. Thermal glycol energy to heat water. In this method (indirect circulation), glycol is heated by natural sunlight and the heat is then transferred to water in a warm water tank. This method of collecting the sun's energy is a lot more practical now than ever before. In areas as far north as Edmonton, Alberta, solar thermal to heat water is economically sound. It can pay for itself in 3 years or less.
4. Integrating solar photovoltaic energy into your home or office power. In lots of parts of the world, solar photovoltaics is an economically feasible method to supplement the power of your own home. In Japan, photovoltaics are competitive with other forms of power. In america, new incentive programs make this form of solar power ever more viable in many states. An increasingly popular and practical way of integrating solar energy into the power of your home or business is through the use of building integrated solar photovoltaics.
5. Large independent photovoltaic systems. When you have enough sun power at your site, you may be able to go off grid. It's also possible to integrate or hybridize your solar power system with wind power or other types of renewable power to stay 'off the grid.'
How do Photovoltaic panels work ?
Silicon is mounted beneath non-reflective glass to produce photovoltaic panels. These panels collect photons from the sun, converting them into DC electrical energy. The power created then flows into an inverter. The inverter transforms the power into basic voltage and AC electric power.
Solar cells are prepared with particular materials called semiconductors for example silicon, which is presently the most generally used. When light hits the Photovoltaic cell, a particular share of it is absorbed inside the semiconductor material. This means that the energy of the absorbed light is given to the semiconductor.
The energy unfastens the electrons, permitting them to run freely. Pv cells also have more than one electric fields that act to compel electrons unfastened by light absorption to flow in a specific direction. This flow of electrons is a current, and by introducing metal links on the top and bottom of the -Photovoltaic cell, the current can be drawn to use it externally.
What are the positives and negatives of solar energy ?
Solar Pro Arguments
- Heating our homes with oil or gas or using electricity from power plants running with coal and oil is a cause of climatic change and climate disruption. Solar energy, on the contrary, is clean and environmentally-friendly.
- Solar hot-water heaters require little maintenance, and their initial investment may be recovered within a relatively limited time.
- Solar hot-water heaters can work in almost any climate, even just in very cold ones. You just need to choose the right system for your climate: drainback, thermosyphon, batch-ICS, etc.
- Maintenance costs of solar powered systems are minimal and the warranties large.
- Financial incentives (USA, Canada, European states…) can help to eliminate the cost of the initial investment in solar technologies. The U.S. government, for example, offers tax credits for solar systems certified by by the SRCC (Solar Rating and Certification Corporation), which amount to 30 percent of the investment (2009-2016 period).
- The first investment in Solar Hot water heaters or in Solar PV Electric Systems is greater than that required by conventional electric and gas heaters systems.
- The payback period of solar PV-electric systems is high, as well as those of solar space heating or solar cooling (only the solar hot water heating payback is short or relatively short).
- Solar water heating do not support a direct in conjunction with radiators (including baseboard ones).
- Some hvac (solar space heating and the solar cooling systems) are expensive, and rather untested technologies: solar air conditioning isn't, till now, a truly economical option.
- The efficiency of solar powered systems is rather determined by sunlight resources. It's in colder climates, where heating or electricity needs are higher, that the efficiency is smaller.
Composed By: Aditya Sharma
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