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 than the four hydrogen atoms that fused. Some matter is lost during nuclear fusion. The lost matter is emitted into space as radiant energy.
It takes an incredible number of years for the energy in the sun’s core to make its way to the solar surface, and then somewhat 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 speed of light.
Only a small part of the energy radiated by the sun into space strikes our planet, one part in two billion. Yet this volume of energy is enormous. Each day enough energy strikes the united states to supply 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 earth is reflected back into space. Another 30 percent is used to evaporate water, which, lifted in to the atmosphere, produces rainfall. Solar power also is absorbed by plants, the land, and the oceans. The remaining could be employed to supply our energy needs.
Who invented solar energy ?
Folks have harnessed solar power 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'd cause wood to catch fire. More than 100 years ago in France, a scientist used heat from a solar collector to produce steam to drive a steam engine. In the beginning of this century scientists and engineers began researching ways to use solar power in earnest. One important development was a remarkably efficient solar boiler invented by Charles Greeley Abbott, an american astrophysicist, in 1936.
The solar water heater became popular at this time in Florida, California, and the Southwest. The industry started in the early 1920s and was in full swing just before World War II. This growth lasted prior to the mid-1950s when low-cost propane became the primary fuel for heating American homes.
People and world governments remained largely indifferent to the possibilities of solar technology before the oil shortages of the 1970s. Today, people use solar power to heat buildings and water and also to generate electricity.
How do we use solar power today ?
Solar power is used in a variety of ways, of course. There are two very basic 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.
Let us discuss the five most practical and popular techniques 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 utilised for everything from RV appliances to traffic signs and remote monitoring stations.
2. Solar pool heating. Running water in direct circulation systems through a solar collector is an extremely practical way 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 sunshine and the heat is then transferred to water in a hot water tank. This process of collecting the sun's energy is much 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 three years or less.
4. Integrating solar photovoltaic energy into your home or office power. In many parts of the world, solar photovoltaics is an economically feasible method to supplement the power of your home. In Japan, photovoltaics are competitive with other forms of power. In the USA, many states have new incentive programs that make this form of solar technology more viable than ever. 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. If you have enough sun power at your site, you may be able to go "off grid." You may also integrate or hybridize your solar power system with wind power or other kinds of sustainable energy 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 energy into basic voltage and AC electrical power.
Photovoltaic 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 specific share of it is absorbed inside the semiconductor material. This means that the energy of the absorbed light is given to the semiconductor.
The power unfastens the electrons, permitting them to run freely. Photovoltaic cells also have one or more 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.
Do you know the advantages and disadvantages of solar power ?
Solar Pro Arguments
- Heating our homes with oil or propane or using electricity from power plants running with oil or coal, which is a contibuting factor to 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 can be recovered in just a relatively limited time.
- Solar hot-water heaters can work in nearly every climate, even 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 also the warranties large.
- Financial incentives (USA, Canada, European states…) can aid in eliminating the price of the first investment in solar technologies. The U.S. government, for instance, 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).
Solar Cons Arguments
- The first investment in Solar Hot water heaters or in Photovoltaic 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 warm water heating payback is short or relatively short).
- Some air con (solar space heating and the solar cooling systems) are expensive, and rather untested technologies: solar ac isn't, till now, a truly economical option.
- The efficiency of solar powered systems is influenced by sunlight resources. It's in colder climates, where heating or electricity needs are higher, that the efficiency is smaller.
About the writer - Barbara Young writes on
RV solar charger in her personal hobby website 12voltsolarpanels.net. Her work is centered on helping people save energy using solar powered energy to eliminate CO2 emissions and energy dependency.