Fun (Knowledge) Friday ~ Solar Energy

Today I have a guest writer ~ Barbara Young ~ from the blog 12 Volt Solar Panels. Meet Barbara...

Barbara has a passion for...


Solar Energy. Specifically, she is educating all of us on solar power and how it will help preserve our precious Mother Earth. When Barbara contacted me to ask about being a guest writer, I said "show me what you got." She did. Immediately. I read through it and learned myself. I am all for that! I cannot verify all that she wrote but it sounds convincing to me. Give it a read and tell me what you think! Take it away Barbara...

Here’s an easy approach to learn the way solar panels work

What's solar power?

Solar energy is radiant energy which is produced by the sun. Every day the sun radiates, or sends out, an immense quantity of energy. The sun radiates more energy in a single 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 a big ball of gases––mostly hydrogen and helium atoms.

The hydrogen atoms in the sun’s core combine to create 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. But 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 an incredible number of years for the energy in the sun’s core to make its way to the solar surface, and then just a little 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.

Only a small part of the power radiated by the sun into space strikes the earth, one part in two billion. Yet this volume of energy is enormous. Daily enough energy strikes the USA to provide the nation’s energy needs for one and a half years!

Where does all of this energy go?

About 15 percent of the sun’s energy that hits our planet is reflected back into space. Another 30 percent is used to evaporate water, which, lifted in to the atmosphere, produces rainfall. Solar energy is also absorbed by plants, the land, and the oceans. The remaining could be used to supply our energy needs.

Who invented solar energy?

Folks have harnessed solar energy for centuries. Since 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 a century 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 obviously a remarkably efficient solar boiler introduced by Charles Greeley Abbott, a United States 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 The second world war. This growth lasted prior to the mid-1950s when low-cost gas took over as primary fuel for heating American homes.

People and world governments remained largely indifferent to the possibilities of solar technology prior to the oil shortages of the1970s. Today, people use solar technology to heat buildings and water and also to generate electricity.

How we use solar power today?

Solar energy can be used in several different ways, of course. There's two simple forms of solar power:

* 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.

Here are the five most practical and popular methods solar energy can be used:

1. Small portable solar photovoltaic systems. We see these used everywhere, from calculators to solar garden products. Portable units can be used 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 through a solar collector is an extremely practical solution to heat water for your pool or 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 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 on the planet, solar photovoltaics is an economically feasible solution to supplement the power of your own home. In Japan, photovoltaics are competitive with other kinds of power. In America alone, new incentive programs make this form of solar energy 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. For those who have enough sun power at your site, you might be able to go off grid. You may also integrate or hybridize your solar energy system with wind power or other kinds of alternative energy to stay 'off the grid.'

How can 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.

PV cells are prepared with particular materials called semiconductors such as 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. Solar 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 benefits and drawbacks of solar power?

Solar Pro Arguments

- Heating our homes with oil or propane or using electricity from power plants running with coal and oil is a cause of global warming and climate disruption. Solar power, on the other hand, is clean and environmentally-friendly.

- Solar hot-water heaters require little maintenance, and their initial investment could be recovered within a relatively limited time.

- Solar hot-water heaters can work in nearly every climate, even in very cold ones. Simply choose the best system for your climate: drainback, thermosyphon, batch-ICS, etc.

- Maintenance costs of solar powered systems are minimal and also the warranties are large.

- Financial incentives (USA, Canada, European states…) can reduce the cost of the initial investment in solar technologies. The U.S. government, for instance, offers tax credits for solar systems certified by the SRCC (Solar Rating and Certification Corporation), which amount to 30 percent of the investment (2009-2016 period).

Solar Cons Arguments

- The initial investment in Solar Hot water heaters or in Solar PV Electric Systems is higher 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 AC (solar space heating and the solar cooling systems) are expensive, and rather untested technologies: solar air conditioning isn't, until now, a economical option.

- The efficiency of solar powered systems is rather influenced by sunlight resources. It's in colder climates, where heating or electricity needs are higher, that the efficiency is smaller.

About the Author - Barbara Young is the author of her personal hobby blog 12voltsolarpanels.net. Her efforts are centered on helping people save energy using solar power to reduce CO2 emissions and energy dependency.

Do you feel enlightened?