Geo World Resources
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Introduction

Need hot water? Don't want to use electricity or gas? Make your own solar water heater!  Your water heater will run on sun-power. Read the explanation and follow the links below to learn how this works. 

Collect the materials and follow the instructions to build your solar water heater.
      Safety Information
Experiments are dangerous, but scientists are always safe!

→Always have an adult help you collect the materials and conduct the experiment.
→As you know, the sun is very hot. The water you heat will also become very hot. Do not drink or touch this water until it cools a bit.

 

  
Materials
→ 4 Styrafoam panels, 3 ft x 1.5 ft x 1/2 in.
→ 1 styrafoam panel, 3 ft x 3 ft x 1/2 in.
→ wood panel, 3 ft x 3 ft.
→ metal wire and wire cutters
→ silicone clear hose
→ 2 corks about the size of hose opening (not too tight!)
→ glass panel, 3 ft x 3 ft; concave shaped would be even better.
→ window putty
→ drill
→ black paint
→ funnel
→ duct tape
→ a sunny day!
Instructions
1) 

 

 

2)

 Build the base: loosely coil the hose flat against the wooden panel in a spiral shape; drill about 5 holes near the places you will secure the hose.  Also, drill a hole through the wood big enough for one end of the hose to fit through.  Attach the hose to the panel using pieces of the metal wire, looped around the hose, stuck through the holes in the wood, and taped to the bottom of the wood. Cork the inside opening of the hose.  Allow the edge of the hose to stick out at one corner of the wooden panel.

 

Paint the wood base and the hose entirely black. Then, let the paint dry.  

3)

Build the styrafoam topless cube with the wooden panel in the base.  Cut the styrafoam at the bottom and in the corner to allow the hose to stick out at both ends. Use the putty to stick it all together and seal any holes. 

4) Place the glass panel on the top; attach to the styrafoam with putty.
5) 

 

 

 

 

 

 

 

 

 

 

 

6)

 Fill the hose with hot water using a funnel.  You may need to tilt the whole cube to completely fill the hose with water.  Cork the end of the hose loosely.

Let the cube sit in the sun for about fifteen minutes. Your water will be

 

very . . . very . . . HOT!!! 

 

 

 

 

 
Explanation
  You've probably left one of your toys outside on a hot summer day.  What happened to the toy?  It became hot.  If you leave crayons out in the sun, they melt.
  Normally, things get hot in the sun. This is because the sun gives off light; when light is absorbed by an object, it becomes heat.
But this can take a long time, and heat will escape from the object. Your water heater traps the suns heat. How?
  The glass top of the water heater allows the sun's heat to get inside.  Once the heat is inside, it heats the air.  The air cannot escape because you sealed all the holes. The heat is absorbed into the black base, focusing it on the hose.  Inside the hose, of course, is your water. 
  Also, the styrafoam keeps the air inside and insulates the air, helping it stay the same temperature. 
  Scientists are still working on more ways to use solar power.  The only downside is you have to wait for a sunny day!
Links
Solar: The Most Exciting Energy Ever
A student project about solar power
Which Passive Solar Collector Absorbs the Most Heat?
A student project comparing solar water heaters
Do Color and Light Affect Temperature?
A student project explores how color and light affect temperature
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