What is Solar Energy and Solar Power?

To understand what is solar energy and likewise solar power, let's first understand what "energy" is - then let's define what the difference is between solar energy and solar power, even though these terms are often used interchangeably.

Energy is defined as the capacity to do work or to make something happen. There are different forms of energy such as heat, sound, light and motion.

A basic theorem of energy states that energy cannot be destroyed, but it can be transferred or moved from one place to another. An example of this would be the Sun's rays hitting a rock. The Sun's energy is transferred to the rock, heating it up.

Likewise, the Sun's energy can be transferred from one form to another. Solar cells are an example of energy being transformed. Solar cells convert the Sun's rays into electricity, or electrical energy.

So, what is solar energy? it is simply energy specifically from the Sun that can be converted into heat or into electricity.

More about energy in general. Anything that has energy can be used as an energy source. Examples of energy sources include the Sun, wind, moving water from rivers or tides, fossil fuels such as coal, oil, and gas.

We can describe energy into two different types - renewable and non-renewable. We consider renewable sources of energy as those that are continually replaced either by humans or by nature.

Non-renewable energy we consider are from sources that are not replaced such as coal, oil and natural gas.

Renewable energy sources can also be described as alternative or "green" energy because they are less harmful to the environment and produce less noticeable pollution as renewable sources.

More about the Sun. The Sun is not solid; it is made up of a boiling mass of the gasses hydrogen and helium along with smaller amounts of other elements.

Its center, or core, is the heaviest, hottest part of the Sun. At its surface is a cooler layer.

Fusion changes the hydrogen atom into a heavier atom - helium. Energy is released in this process in the form of heat and light.

The heat and light energy created by the Sun's fusion streams out into space in every direction. Light energy travels through space like waves, simply described as like waves on the ocean.

From the time light leaves the Sun, it takes just over eight minutes to reach the Earth.

Of course, only a tiny fraction of the energy emitted by the Sun reaches the Earth, perhaps only about one or two-billionth. This is actually a huge amount of energy.

It is estimated that the sunlight that reaches the earth in one hour is as powerful as all the oil, gas, electricity and other energy sources used on the entire planet in one year.

The use of non-renewable energy sources is much cheaper and easier - in a sense the solar energy has already been contained; it just needs to be release through burning.

Because of the voracious appetite for energy, non-renewable energy sources are being depleted, causing prices to rise and supplies to threatened. This is similar to what happened in ancient Greece and Rome with their wood and coal supplies. [text link to history pages] Understanding and awareness about what is solar energy and how solar power can be used is again a practical question for many people in many countries.

Once again, like in the ancient world, the conditions are set for the use of solar energy and its conversion into solar power.