1. What are some pros and cons of solar energy?
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What are some pros and cons of solar energy?

2. answer
Some advantages of solar energy are: it will never run out, it is clean and does not create pollution, and it is available everywhere in the world.
Some disadvantages are: you cannot use it at night or on cloudy days, it is hard to store, and solar panels are expensive to build and run.

3. Solar energy and the photovoltaic effect
Using the sun’s energy!

4. Question: how does sunlight get converted to electricity?!?

5. Two kinds of solar energy
1. Radiant energy
Provides light energy and heat energy.
Used by plants for photosynthesis.
Needed to keep our planet the optimal temperature for life on earth.

6. 2. Solar energy to produce electricity from the PHOTOVOLTAIC EFFECT.

7. The photovoltaic effect
Sunlight contains PHOTONS, or “packets of energy”.
When photons strike a solar cell or solar panel, made out of SILICON (a semiconductor), they “loosen” electrons.

8. The electrons move through wires as an electric current, and can power appliances and devices.

9. Examples of solar panels

10. Can solar energy be stored?
Solar panels cannot produce energy at night or during cloudy periods.
Solution: Photovoltaic panels can charge rechargeable batteries during the day, and this power can be drawn upon in the evening.

11. Video clip
Watch this video clip about how the PHOTOVOLTAIC EFFECT occurs in silicon, and some of the pros and cons of using it!