Solar energy

From SCOUTS South Africa Wiki
Jump to navigation Jump to search

For the Conservation section of the Gold Wolf Awareness Challenge, Cubs need to "Heat water using solar energy OR use solar energy to cook something."

We are very lucky in South Africa because we have plenty of hot sunshine for most of the year. Solar energy is the power given off by the sun. You can feel the heat from the sun, but you can't see it.

Experiment

Have you noticed that a dark object left in the sun gets hotter than a light object? You can try this experiment: leave a piece of black paper of cloth and a piece of white paper or cloth in the sun. After a while, feel each of them and you will see that the black object is warmer than the light one.

A simple way to heat water using the sun

It is easy to heat water using the sun's energy. Fill a plastic bag or a bottle with water, and leave it lying in the sun. On a warm day, you'll be surprised how hot it can get! If you want it to get hot faster, use a black plastic bag or place a clear bag on something black.

Things to remember:

  • The hotter the day, the warmer the water will get.
  • The warmer and drier the surface you place it on, the warmer the water will be. If you put your container of water on bricks or dry sand, it will get much warmer thamn if you put it on damp soil or on the lawn.
  • The smaller the amount of water, the faster it will warm up.
  • Always make sure the container faces the sun. You will need to check your container regularly and turn it if necessary.
  • Using the sun's energy to heat something takes time, so start early, and be patient.

Making a solar reflector oven

You can use reflectors to collect more heat from the sun and concentrate it on a smaller area. This will help to heat up faster. Here are some ideas you can try:

You can use your oven to heat water, and maybe use a thermometer to see how hot the water gets. You can also use it to make smores - melted chocolate and marshmallows on marie biscuits.