Solar Panels

Welcome To Science CCA!Welcome To Science CCA!

Today, we will be talking about harnessing the power of the sun

through Solar Panels! What are Solar Panels and how do they work? How would you get power/electricity from

the sun? We will find out…

Solar Panels and How They Solar Panels and How They WorkWork

By Jay Glaus

First… A Brief Introduction

About The Sun

Generates it’s energy through nuclear fusion

Needed to make the earth function:

-Photosynthesis for plants

-Provides solar energy

-Evaporation > Rain

-MUCH MORE

The Sun & The Earth

See the position of all theplanets at the current time

http://www.fourmilab.ch/cgi-bin/Solar

The Sun’s Rays Enter the Earth’s Atmosphere

The Atmosphere

Solar radiation first hits the atmosphere in this layer and ionizes air molecules. A region of ionized particles in the thermosphere is called the ionosphere. Auroras, which are interactions of charged solar particles and the ionosphere, can be seen in this layer of the atmosphere. Temperature is up due to ionization of air molecules by solar radiation. Air is extremely thin.

Auroras in the Thermosphere

An aurora is an interaction of the ionosphere and charged solar particles within the thermosphere.

Aurora – The Northern Lights

The Atmosphere

The stratosphere contains a significant portion of ozone, a molecule consisting of 3 oxygen atoms bound together. Ozone absorbs ultraviolet light from space, thereby protecting life on earth from this dangerous radiation. Temperature is up due to the interaction of ultraviolet light and ozone.

The Atmosphere

Troposphere (where we are) has high temperatures due to molecules absorbing the Sun’s energy.

The Sun’s EnergyWe can tell the Sun’s

energy is present…

The radiation/energy off of the sun heats up pavement, causing you to

see “heat waves”. “Heat waves” look like water almost, causing

mirages in the desert. For example, if you saw that watery look ahead in the desert, you would think there is water ahead, when it is really only

hot sand

The Sun’s EnergyWe can tell the Sun’s

energy is present…

Radiation/energy from the sun can also heat swimming pools.

The Sun’s energy is out there, but how can we convert it into electrical

power?

What is the missing link to take the sun’s energy and convert it into electrical energy?

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Solar Panels

Solar Panels can do just that!

How Solar Panels Work

The basic element of solar panels is the same element that helped create the computer revolution -- pure silicon.

How Solar Panels Work

When silicon is stripped of all impurities, it makes a ideal neutral platform for the transmission of electrons. Silicon

also has some atomic-level properties which make it even more attractive for the creation of solar panels.

Silicon atoms have room for eight electrons in their outer bands, but only carry four in their natural state. This

means there is room for four more electrons.

How Solar Panels Work

If one silicon atom contacts another silicon atom, each receives the other atom's four electrons. This creates a strong bond, but there is no positive or negative charge because the eight electrons satisfy the atoms' needs.

Silicon atoms can combine for years to result in a large piece of pure silicon. This material is used to form the

plates of solar panels.

How Solar Panels Work

Here's where science enters the picture. Two plates of pure silicon would not generate electricity in solar panels, because they have no positive or negative charge. Solar panels are created by combining

silicon with other elements that do have positive or negative charges. Phosphorus, for example, has five electrons to offer to

other atoms. If silicon and phosphorus are combined chemically, the result is a stable eight electrons with an additional free electron

along for the ride. It can't leave, because it is bonded to the other phosphorus atoms, but it isn't needed by the silicon. Therefore, this

new silicon/phosphorus plate is considered to be negatively charged.

How Solar Panels Work

In order for electricity to flow, a positive charge must also be created. This is achieved in solar panels by

combining silicon with an element such as boron, which only has three electrons to offer. A silicon/boron plate still has one spot left for another electron. This means

the plate has a positive charge. The two plates are sandwiched together in solar panels, with conductive

wires running between them.

How Solar Panels Work

With the two plates in place, it's now time to bring in the 'solar' aspect of solar panels. Natural sunlight sends out

many different particles of energy, but the one we're most interested in is called a photon. A photon

essentially acts like a moving hammer. When the negative plates of solar cells are pointed at a proper

angle to the sun, photons bombard the silicon/phosphorus atoms.

How Solar Panels Work

Eventually, the 9th electron, which wants to be free anyway, is knocked off the outer ring. This electron doesn't remain free for long, since the positive silicon/boron plate

draws it into the open spot on its own outer band.

How Solar Panels Work

As the sun's photons break off more electrons, electricity is generated.

Solar Power PlantsSolar Power Plants have massive

amounts of solar panels to power their city. Rizhao City, in China is converting to solar energy. There is construction going on to build a solar power plant in Nevada, that will meet the needs of about 40,000 households with solar energy.

Sun goes down, Lights go out???

Many people think that when the sun goes down, or we have a cloudy day, no energy would be produced, leaving us in the dark. That theory is not true. In fact, even with clouds, some rays from the sun still get through, just not as many on a clear day. Also, when the solar panels collect energy during the day, not all of it is used. What isn’t used is stored in giant batteries at the plant so there is always a reserve. However, it would be quite a test in Alaska, because the reserve may not hold out for three months!

Batteries to hold Solar Power

These batteries are small batteries to hold solar power

Batteries to hold Solar Power

These are heavy-duty batteries that could be used at a solar power plant to hold some of the reserve power.

Could your house “go green”?

Yes, it is possible. Houses have already gone to solar power. They put solar panels on their roof to collect sunlight and have batteries in their basement to store the reserve power. Some have even put up solar panels in their yards.

Solar Powered House

Disney World & The Environment

Disney World in Disney World in Orlando Orlando

Florida has Florida has gone green. gone green.

They provide They provide their own their own

power, they power, they treat their own treat their own sewage... All in sewage... All in all, they’re self all, they’re self

sufficient.sufficient.

Solar Powered Wii

The Nintendo Wii has gone Green!!!

Want to try some Solar Power?You do not need tens of thousands of solar panels just to

power something. You can power small electronics with a small solar panel you can use!

10 Watt - http://www.ccrane.com/more-categories/alternative-power/10-watt-solar-panel.aspx

2.5 Watt - http://www.ccrane.com/more-categories/alternative-power/2-watt-solar-panel.aspx

Want to try some Solar Power?

Color changing LED Solar Patio Light

Want to try some Solar Power?

Sidewalk Strand of Solar Powered

Lights

Want to try some Solar Power?

Solar Powered Lights

Just “Google” Solar Lights!!!

Solar Powered Spot Light

Solar Powered Spot Light

Solar Panel

Excellent External Sites

http://www.wisegeek.com/how-do-solar-panels-work.htm

Explains How Solar Panels/Cells Work

http://www.renewableenergyaccess.com/rea/news/story?id=48605

China’s Solar Powered City

http://news.mongabay.com/2006/0209-solar.html

Solar Power Plant in Nevada

http://ccrane.com

Buy Solar Panels & Neat Electronics

I hope you enjoyed the presentation!