EXPERIMENT 1

A Model Solar Hot Water Heater

This experiment will help you understand how solar hot water heaters operate. Many people around the country are installing such systems in their homes. Perhaps someone in your neighborhood has done so.

     The heart of a solar hot water heater is a device called a collector. It collects, or captures, solar energy and uses that energy to heat water. In a real solar hot water heater installation, the collector is large and is mounted on the roof of the house. The collector must be aimed toward the south so that it collects the maximum possible amount of sunlight during each day.

     You can easily build a model solar energy collector. Start by covering the inside of the box with black paint, paper, cloth, or other dark material. Then loop the tubing back and forth inside the box. Arrange for both ends of the tubing to be sticking out of the sides of the box a couple of feet.

     Next, place the glass cover on the box and secure it with tape. We’re now ready for a test.

     Wait for a sunny day and find an open area. Place the collector on a stand, with a can or bucket of water next to the collector. Put one of the tubing ends into the water. Suck gently on the other end to establish a siphon action. Once water starts to flow through the tubing, pinch the tubing partially with the clothespin to limit the flow of water to a small trickle.