How is solar power used to make electricity?
Question:
Answer:
Solar energy?
The sun (in nuclear fusion) produce energy in the form of electromagnetic radiation. It can be used/transformed into potential-chemical energy by being stored in glucose molecules (done by chloroplasts in plants) which actually (in principle) work similarly to solar pannels. If an electromagnetic wave hit an electron (and it has enough energy) it will excite the electron, and may cause it to be knocked of. Solar pannels are semi-conductors, the electrons in them get excited creating a flow of electrons.
Photovoltaic cells in the solar panels hold the heat from the sun in stasis through photo-electric effect. The heat is thereby transfered into energy, which is the power source of the electricity. The more heat=the faster the molecules move=more heat=more photo-electric effect=more electricity.
1. Photovoltaic effect (e.g. Si photocells) use the energy of photons to move electrons (or "holes", spaces where electrons are deficient). The photoelectric effect does _not_ depend on heat; heat can reduce the efficiency of or damage the cells. This is used in small (e.g. a single flashlight) and large installations.
2. Solar concentrators: arrays of mirrors that focus on a boiler used to run a "standard" steam-powered generator. This is useful for large installations only.
3. One could stretch the definition a bit: a wood- or bagasse-fired power-plant is one step removed form direct solar power.
1. By direct conversion to electricity. Some materials emit electrons when impinged by light rays.
2. By artificial conversion of the light to heat. The heat is then used to generate electricity by any means that non-solar methods do, such as steam turbines, etc.
3. By natural conversion of the light to heat, which has effects, such as wind, that may be used to generate electricity.
4. By natural conversion of the light into plant matter, which may be used (typically burned or made into petroleum or coal which is burned) to generate electricity. Nobody calls this solar power though, but that's what it is.
5. Sunlight is wrapped in a box and is presented as a gift to the Electricity Fairy, who may or may not give you any electricity, depending on the time of the month. (Hint: Try to get a government grant to study this.)
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