Learn about nonrenewable and renewable energy sources

From heating and cooling our homes to playing video games, energy is everywhere in our daily lives. But did you know that a lot of energy comes from nonrenewable sources?

Nonrenewable means it can’t be replaced. Natural gas, coal, and nuclear energy aren’t renewable. If we use it all, it will be gone forever. But we’ll need energy for years to come.

Did you know?

The sun shines every day, so solar energy is available all the time! We do have to store it for cloudy days, but there is plenty of sunshine to go around.

This is an important problem we’ll have to solve by finding renewable energy resources, which are resources that don’t run out when we use them. Today, you’ll learn about solar energy!

Did you know?

Solar energy doesn’t produce chemicals that are bad for humans or bad for the environment!

Discover how photovoltaic solar energy works

Let’s talk about how photovoltaic solar energy works! We’ll call it PV throughout the rest of the lesson.

Have you ever seen a large field of solar panels laid out in rows or squares to catch the sun? Maybe there are solar panels on the roof of some houses or buildings in your neighborhood.  These panels are used to produce photovoltaic solar energy (PV).

A solar cell is an electronic device that converts the energy of light into electricity.  It has a few parts that help it work.

• A metal base helps the generated electricity flow back to the PV system.
• Solar cells contain silicon. Silicon is a semiconductor. It helps the electricity flow, but not as strongly as metal does.
• The protective glass protects the silicon and conductive metal from damage.

There are important words for describing what happens in creating solar power! Do you know these terms?

• Photon – the energy that comes to Earth from the sun.
• Semiconductors – anything that helps conduct electricity.
• Silicon – a metal-like element used to help conduct electricity in solar cells

Did you know?

Solar energy is the most abundant type of energy because it is available every day, and almost everywhere in the world. The trick is learning how to harness this energy.

Now that you’ve learned how PV works, it is time to create your own model! Solar energy comes to the earth in particles of energy called photons. When the photons reach a solar cell, the semiconductor absorbs the energy, creating an electric charge, causing electricity to flow through the conductive metal base and into a PV system, creating electricity for houses and businesses.

Create a Photovoltaic Solar Energy (PV) Model

The city you live in has decided to use your city park to produce PV energy, and they have hired you to design the PV field in an area of the park that isn’t used very often.

There are a few things you should know before you start designing your PV field.

• Solar panels are most effective when they face south.
• Solar panels should be connected in lines so that the energy gathered can be collected together.
• Solar panels work best when they are tipped at an angle to absorb the sun better.

Using the index cards and tape, create a model of a PV field.

Did you know?

Solar energy has been used for thousands of years. Glass lenses were used to magnify the sun’s rays to start fires in 700 BC. Many civilizations have used south-facing windows to heat houses long before we learned how to harness electricity.

Not sure where to start? Check out the pictures below of different PV fields and see if that inspires you! There is no right or wrong way to design your PV field.

Learn about other types of solar energy

Like PV, solar thermal energy (STE) collects the sun’s energy for human use. Unlike PV, which converts the sun’s energy to electricity, STE stores heat energy from the sun for future use. It is often used to heat water.  A solar water heater uses a collector and a water storage tank. The heat from the sun is used to warm up water, which is then used in a home or business.  For a few years, the White House used a system like this for hot water! Below is pictured the solar panels on the White House when Jimmy Carter was president.

Did you know?

Satellites, spacecraft that orbit Earth, often use solar power. These spacecraft have solar panels to convert the sun’s energy into electricity, which charges batteries to power things in the satellite.

Concentrated Solar Power (CSP) generates energy by using mirrors to reflect sunlight from the Earth. It is often used to create steam to power a generator and create electricity.   It looks similar to PV, but the curved mirrors don’t absorb sunlight to directly create electricity.

Passive solar energy uses glass, stone, and air to distribute heat through homes. Passive solar energy systems capture sunlight using building materials to release heat during periods when the sun is absent. When the winter sun goes through the glass on the south side of a house designed for passive solar energy use, the house can capture and concentrate heat. The heat is held by brick or stone the house is built of. The heat from the stone is then distributed throughout the house. In the summer when heat is not needed, an overhang blocks the sun from entering the glass.

Redesign your solar energy model

Look back at your solar energy design. Ask yourself the following questions to see if you can improve your design!

• Would a real version of your model hold up to wind, rain, and snow?
• Are there changes you could make to help it last longer?
• What changes could you make to help it collect and store even more solar energy?