How does solar energy become electricity?
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Question by genieraw: How does solar energy become electricity?
In both ways, how do the solar panels turn it into electricity and how do the solar power stations turn it into electricity.
I know it sounds simple, but I actually can’t find an answer that I can understand!
Word it simply please? I’m a stupid person. (:
Can you help? Leave your own answer in the comments!
3 Responses to How does solar energy become electricity?
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The dirt-simple answer (but actually, pretty true in a deep sense) goes like this. All atoms have electrons. If an atom absorbs a light photon of the correct energy level, an electron will break free. If the atom happens to be surrounded by a bunch of similar atoms, that tend to be conductive, and a lot of them are getting hit by photons, you get a lot of electrons moving. And if they’re all moving in the same direction, more or less, we call it electricity.
The important part is that you need a material that’s both reasonably conductive and will release an electron when hit by sunlight.
mukansamonkey
May 18, 2013 at 10:19 pm
To illustrate how PV works, let’s follow the flow of energy through a small grid-tied residential system:
The first step in the process occurs when rays of light from the sun strike the cells within PV modules (modules are commonly called “panels”). As the light energy hits the photovoltaic cells, electrons are excited and begin to flow. Multiple cells are connected in one module, and several modules are connected together to form an array, all harnessing and summing the flow of this electric power.
The current produced in the PV modules is Direct Current (DC). However, most of the lights, appliances, and other electrical equipment in our homes operate on Alternating Current (AC). Next in the chain of energy flow is a device called an inverter, which gathers the DC produced by the array and converts it to AC which can be used in the home. The inverter regulates the AC power it outputs, so it can be safely used by even sensitive electronic devices such as televisions, computers, and audio equipment.
The AC output of the inverter is connected to the home’s main service panel, where it intermingles with the AC power supplied by the local electric utility. Net Metering refers to the physical (and financial) ability of a home’s electric meter to “run in both directions”. We are accustomed to power only flowing from the utility to the loads in our house. However, with the house now acting like a mini utility producing its own electricity, there will likely be times when electricity actually flows out of the house and to the utility.
A PV array produces electricity whenever the sun shines on it. This is true from sunrise until sunset, and often times even after the sun sets! (A full moon on a clear night can actually produce small amounts of current from a PV system.) Generally speaking, an array will produce its maximum power between roughly 9:00am and 3:00pm. During those hours, with the array pushing a strong flow of DC power into the inverter, and the inverter in turn delivering a strong flow of AC to the home, it is very likely that there will be a surplus of electric power available at the house. Why? During these hours, many homes are empty, while their occupants are off to work or school. Even for those at home during the day, their need for artificial lighting (typically about 25% of a home’s electricity consumption) will be much lower.
It is at night, when the members of our hypothetical family return home, that the electricity demand from the house increases as lights, air conditioners, televisions, and other loads are turned on. At the same time, the output of the PV system is winding down as the sun sets for the day. During these hours, the house will be a demander of power from the utility, rather than a supplier. Net metering keeps track of the net inflows and outflows of electricity throughout a billing period. The customer pays for what they use, minus the production of their array which is “sold back” to the utility.
Installing a photovoltaic electric generating system at your home or business will greatly reduce your energy costs and will have environmental benefits because it produces clean, green energy right here in the USA.
Jon
May 18, 2013 at 10:35 pm
Simply put the solar panels on your roof absorb the sun’s energy which is called DC and all that energy is placed in an inverter (you have to make sure the inverter you have is highly efficient) the inverter then converts that energy to AC and transfers it into your home for the normal use of electricity
Hope that helps
Sarah Summers
May 18, 2013 at 11:14 pm