How do we get energy from the sun?

Question: How do we get energy from the sun?

Asked by anon-201683 to George, Emily on 12 Mar 2019.
- George Fulton answered on 12 Mar 2019:
  
  The sun emits lots of waves called electromagnetic radiation. The part of the waves that we can see is ‘light’. Light is a form of energy. (It takes electricity to turn on a light-bulb right?) Solar panels act to capture this light by exciting electrons in special materials called semi-conductors. The electrons takes the energy from the light and this can be used to make electricity. This is why solar panels are black, they absorb all the waves in the light spectrum, so that we don’t see a colour from them 🙂 In fact, material scientists get quite excited if they find a new semi-conducting material that is black because of this very reason! Plants learnt how to get energy from the sun a long time before humans did in a process called photosynthesis 🙂 If you’d like a more sophisticated explanation for this, then let me know and I can give you one.
- Emily Lewis answered on 13 Mar 2019:
  
  Almost all the energy we have on earth comes from the sun!
  As George says, we can turn sunlight into electrical power directly using solar panels.
  But the best way is by photosynthesis which happens in plants, they turn solar into chemical energy really really efficiently. Then that energy is passed to us and other animals when we eat plants, our body breaks down the plant so that we can gain that chemical energy to keep us alive.
  On top of that, if animals and plants die and get buried underground for many years they get turned into coal and oil. We dig out the coal and oil and burn it as fuel in power plants to make electrical energy. Almost every energy source we have is related to the sun in some way 🙂

Question: How do we get energy from the sun?

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