Solar Energy
Solar EnergyWith the price of non-renewable energy sources soaring, Kidzworld takes a look at the environmentally friendly energy source we all know and love - our sun! Get the goods on solar energy right here!
How It Works
Solar energy is the energy we acquire from
the sun. Millions of years before humans realized the sun's potential as a
renewable energy source, plants were using the sun's energy to convert
carbon dioxide and
water into sugars to eat. This process is called
photosynthesis. Today, we have tried to copy
plants by creating something called
photovoltaic (PV) cells. These man-made cells are comprised of semiconductors, which are materials that are able to
absorb light energy. The most commonly used semiconductor today is silicon because it is, so far, the most
cost-effective material. The silicon absorbs a
portion of the energy from the light that shines down on it,
electrons are suddenly knocked free and are channeled to flow in the same direction by electric fields within
the PV cell. On both the top and bottom of the silicon, metal contacts are placed and, through these contacts, the solar energy is
extracted and stored.
Practical Uses
Solar energy is used for a variety of different things but the ones that you are most familiar with are solar-powered
calculators, solar-heated
swimming pools and maybe even the hot water
in your house is heated by solar panels. Because solar energy is
clean and renewable, it would be ideal to
make a move from non-renewable
heating sources like
gas to solar on a grander scale, so research is ongoing to make solar energy a more
cost-effective alternative for people around the world.
Did U Know?
Solar energy is measured in kilowatt-hours. One kilowatt hour (kWh) is the amount of energy needed to burn a 100 watt light bulb for 10 hours.
Enough sunlight falls to Earth every hour to meet the world's energy demands for an entire year - the trick is learning how to extract that energy in a cost-effective way.
Approximately 10,000 homes in the United States are run entirely on solar power.
Solar energy can even be used to cook food!
Related Stories:
Fossil Fuel Energy
Hydro Energy
Wind Energy
Understanding Global Warming
More Science From The Lab!
Read more: The Lab