Scientists tell us that our sun is dying. It will, in time, run out of fuel, cool down and expand into a red giant. But as that is going to take approximately 5 billion years, we have plenty of time to take advantage of the solar energy which it currently provides.
The sun is a huge ball of atomic activity, which emits solar energy in the form of light and heat. This energy travels through space to the planets providing us with daylight and warmth. It is an incredible free gift.
Man has always used solar energy as best he can. Early man learned how to use the sun