The Sun's Energy
In the picture, you can see how the sun's energy distributes. In the core of the sun, temperatures and pressure are so high that hydrogen atoms fuse into helium at a rate of 600 million tons per second. Because of this, the sun puts out 386 billion megawatts of energy. 30% is reflected back into space, 20% is absorbed by the atmosphere, and 50% passes through the atmosphere and is absorbed by the earth. 89,000 hits the earth, but only 15 terawatts are used by humans, leaving 5900 times more energy just floating around.
What does the energy do?
The sun's energy powers every natural thing on earth. It gives plants food, and it's warmth makes sure that the earth doesn't freeze over.
How can it harm us?
Anyone who's gotten a sunburn can tell you that the sun isn't all good. As stated previously, lots of the sun's energy is absorbed, making the world warmer. However greenhouse gases are thickening the atmosphere, making energy that should be reflected back into space be absorbed, trapping the heat inside and warming the earth