Getting Electricity From The Sun

 

Courtesy FreeDigitalPhotos.net

Courtesy FreeDigitalPhotos.net

The Most Complete List of Solar Energy Facts on the net!

Ok, so let’s state the obvious. The Sun’s photovoltaic energy is responsible for much of the continuation of life on earth. Don’t believe me? Look at plants and plankton. They make our oxygen, which creates ozone, which protects us from the sun.

Plants create most of the food on the planet for everything from whales to grasshoppers. Even the dead dinosaurs that we burn in our cars ( fossil fuel) is derived, from animals which once lived off of plants.

Today, much of our food, lumber and fuel is derived from plants.

Let’s face it. Photosynthesis is awesome.

But will we ever see solar energy become one of our primary sources of power?

Here are some interesting facts about the power of the sun and our modern photovoltaic systems.

Cool Video About Solar Potential

How Does Solar Energy Work?

There are two types of solar energy technology that are currently used: Photovoltaic and Thermal.

Photovoltaic Energy is created when sunlight photons hit a solar panel, knocking electrons in the material loose and creating an electrical current. Here is a more in-depth explanation I’ve written on how solar panels work.

Solar Thermal Energy is turning out to be much easier to harness. We all know the sun gives off heat, so solar thermal energy is simply harnessing that heat via collectors and using it to power solar-powered electricity plants, roof-mounted hot water heaters and solar pool warmers.

Solar thermal energy actually seems to hold some of the largest potential as far as electrical production goes. Some of the largest electrical plants currently in the nation — for that matter, in the world — is created by solar thermal energy, as opposed to by photovoltaic cells.

If you are looking for Solar Energy Facts for Kids, try scrolling down towards the bottom of the page. Hopefully some of these facts and ideas will help with lesson plans

Interesting Facts About the Sun

solar panel array

Courtesy FreeDigitalPhotos.net

  • One Million Earths could fit inside of the the Sun
  • Sunlight takes 8.3 minutes to reach earth’s outer atmosphere. The sun could disappear and we would still receive sunlight for 8 minutes
  • In one hour, enough sunlight strikes the Earth to provide the entire planet’s energy needs for one year.
  • Fossil Fuel is a form of stored solar energy. Biomass that formerly used Solar energy has been changed into fuel by earth’s geologic activity.
  • About 50% of that sunlight reaches earth and is absorbed by its surface. Approximately 30% of the sunlight is reflected back by the earth’s surface.
  • About 1,366 watts per square meter of energy reaches the earth atmosphere. Depending on location, about 1,000 watts per square meter reaches the ground per hour.

Photovoltaic Solar Panel Facts

  • Solar Panels are considered to be somewhat inefficient as they can only convert a maximum of about 20% of the sunlight they are presented with. By comparison, a gasoline engine is about 18% efficient and a diesel engine is nearly 50% efficient. Solar Thermal Energy is approaching 30% to 40% efficiency using Stirling engines, and anywhere from 25% to 35% using solar powered steam generators.
  • Solar panels will not reach grid parity — matching the cost of current energy production — until it reaches $1 per watt to build panels.
  • Some estimates put solar panels output at about 10 watts per square foot
  • A highly-efficient solar panel (one square meter in size ) can produce up to 1.4 kWh/ day depending on location. The further you are away from the equator, the less sunlight — or insolation — will your area receive.
  • Depending where you live, you may need more solar panels to account for shorter days and less sun. See our Full Solar Report for more calculations

Using The Sun’s Heat To Generate Power

  • According to Schott a German-Based solar manufacturer, Solar Thermal energy costs about 15 cents per Kilo-watt hour. That is only about 5 cents more per kilowatt than conventional solar energy typically costs
  • The efficiency of solar thermal electrical plants increases the more concentrated the heat is.
  • Solar thermal power plants typically use either parabolic systems to collect heat, or a mirror array to concentrate the power on a main power
  • Concentrated solar power plants are more efficient, however the costs of creating tracking systems for the solar panel arrays are also more expensive. Plus, material must be used that can handle temperatures above 800 degrees Celsius.

Facts About Home Solar Energy Systems

  • More than 10,000 homes in the United States have solar energy installed.
  • Solar panels cost about $3-4 per watt for a grid-tied system. Stand-alone systems with full battery backups are considerably more. Complete grid-tie kits (with the required inverter!) can be purchased from retailers such as Amazon and Sams Club at about $4 per watt.
  • Solar panels typically increase the value of your home. Currently, homes in Southern California that have solar panels installed currently have an increased home value of approximately $5.50 per watt of solar energy. That means that a solar panel system that costs $20,000 to install could bring a return $30,000+ (for a 5 Kilowatt system).
  • There are many government and state programs that provide incentives and reimbursements for installing solar panels.
  • Depending where you live, you may need more solar panels to account for shorter days and less sun. See our Full Solar Report for more calculations on solar concentrations

Solar Energy Vehicle Racing

  • Solar powered vehicle races have been around since 1985.
  • The World Solar Challenge and the North American Solar Challenge are two of the largest such races held each year
  • The World Solar Challenge is in Australia and covers 1877 miles across the continent. The solar powered cars exceed 90 mph!

Largest Solar Plants In The World

  • The largest photovoltaic power plant is in Sarnia, Canada. It has an 97 megawatt capacity. Most large power plant installations instead rely on solar thermal energy due to its efficiency.
  • The world’s largest solar energy station is currently the collection of 9 power plants called the Solar Energy Generating Systems (SEGS) developed in the 80’s out in the Mojave desert with a production capacity of 354 Megawatts (MW).
  • Spain also has two large power plants. The Solnova plant is three 50 MW towers for a total potential of 150MW. The Andasol plant takes the title as second-largest behind the SEGS facility with five, 50MW plants for a total output potential of 250 MW.

Facts About Current US Energy Usage

  • 8% of all energy usage in the United States is created by alternative energy.
  • Solar energy only accounts for 0.2% of that.
  • Nuclear Electric Power – 9%
  • Coal Power – 21%
  • Natural Gas – 25%
  • Petroleum – 37%

(eia.gov)

Facts About Current US Alternative Energy Usage

  • Renewable energy accounts for 8% of the United States Energy Usage. It is broken down as below:
  • Of the Alternative energy sources, Solar Energy creates about 1% of that energy.
  • Geothermal Energy accounts for about 5%
  • Wind Energy is 9%
  • Biofuels is 20%
  • Wood is 24%
  • Hydropower is 35%
  • The United States is second in producing renewable energy, behind China.

(eia.gov)

History of Solar Power

  • In the 15th century, Leonardo Di Vinci was one of the first to design an industrial use for the sun. He designed a system of concave mirrors to heat water.
  • The photovoltaic properties of certain silicons were discovered in 1954 by Bell Laboratories. The first functional photovoltaic panels were developed for use on satellites.

Experiment Ideas For Kids – Demonstrate the Power of Sunshine!

The sun is VERY dangerous. Especially when working with mirrors and magnifying glasses. Children should never be allowed to handle equipment that could be hot or redirect sun rays as blindness and burns could easily result. thesolarenergyfacts.net takes no responsibility for any damages

As with any good experiment, make sure that your experiment provides a:

    Question
    Hypothesis
    An Experiment with a Control, an Independent variable and a Dependant variable.

The Sun provides about 300 BTUs of heat per square foot per day. You might try experiments that demonstrate this heat:

  • Cooking eggs in on a sidewalk, or on a frying pan laid in the sun.
  • Using a magnifying glass to ignite paper
  • Thermometer under glass, dark paper, light paper and in open air to compare results. For a more visual effect you could use ice cubes instead of thermometers to show the differences
  • More Resources for Teaching About Sunlight