It's never too early for your preschooler to learn about alternate sources of energy and how they can provide a cleaner source of power. Solar energy is the easiest option for your child to learn about, and he can harness the power of the sun to do creative things. You will need to help him and supply some simple recycled materials to complete his easy solar projects.
Warmer or Cooler
Some colors absorb sunlight and become warm and other colors reflect sunlight and stay cool. Have your preschooler learn which colors absorb or reflect the best. Paint one can black inside and out with non-toxic paint. Paint a second can white inside and out. Choose additional colors such as red and green to paint an additional can, and leave one can silver inside and out. After the paint dries, fill each can mostly full of water and measure the temperature of the water. Cover the top of each can with a plain white index card and set all the covered cans in the full sun. After 30 minutes, measure the temperature of the water in each can. Let your little one arrange the cans from the warmest to the coolest. You might say, “When it’s cold outside you can wear a color that helps you stay warm. When it’s hot, you can choose clothing in a color that helps you stay cool.”
Solar cookers are simple to make and efficient if you place the cooker where the sun shines on your food. If you have access to a tire and a piece of plywood, you can stuff the interior of the tire with newspaper and paint it black. Place a black garbage bag on the wood and set the tire on top of the bag. Place a plate with a couple of hot dogs on a plate and set the plate on the garbage bag inside the tire. Cover the tire with a clear sheet of plexiglass and allow the sun to bake your hot dogs for 20 minutes.
Warm water is better than cold water for a bath. Cover a large plastic bottle with black paint or construction paper and fill it with cool water. Place a plastic tube inside the bottle with a clamp on the tube. Secure the tube to the bottle so that one end of the tube lies on the bottom of the bottle. Let the bottle sit in the full sun for at least an hour. Unclamp the tube and apply a little suction to the end of the tube outside the bottle. The water that comes out will be much warmer than the water that went in.
The sun can help you remove the salt from water so you can drink it. Mix some salt in tap water and let your child taste that the water is salty. Place the salt water inside a large bowl and set it inside a box painted black on the inside and outside. Set a tall, heavy glass in the center of the bowl and set both inside the box. The glass should be shorter than the top of the box. Cover the box tightly with a clear plastic bag, such as a dry cleaner bag. Place a stone on the plastic bag over the glass so the plastic sinks down towards the glass, but doesn’t touch the glass. Set the box in the full sun. The water will evaporate inside the bowl, condense on the bag and flow down the plastic to drop inside the glass. In a couple of hours, your little one can taste the water in the glass and find that it is salt-free.