BY LIAN MLODZIENSKI
SC Contributing Writer
Due to a growing population, energy consumption is on the rise. This means that the cost to efficiently produce enough energy from an economic and an environmental standpoint is also increasing.
Scientists believe that at some point in the future, people will have depleted all available fossil fuels. While this concern may or may not come true, many people find it important to look into more environmentally safe energy sources.
Some other possible energy sources come from wind, water, and the sun. These all appear to be promising options, but due to its cost effectiveness, solar energy is becoming the most prominent candidate for clean energy.
According to Ecotricity.co.uk, “The sun supplies about 1,000 watts of energy per square metre of Earth’s surface.” Unlike trying to find strong winds or a moving water source, the sun shines over the entire globe.
The idea of harnessing the sun’s power started with the National Aeronautics and Space Administration (NASA). When satellites and other space equipment are in outer space, they need a power source.
When NASA began the endeavor of using solar energy, only they could afford it. Now it is becoming more commonplace and less costly. For example, before solar panels could only be found on satellites and now they can be found on some calculators.
Solar panels are more technically known as photovoltaic panels or cells. The breakdown of this technical name refers to how they work. Photo means light and voltaic means electricity. These panels, very literally, turn light into electrical energy.
The traditional cells are made of impure silicon. The silicon used must be impure because if it is not, it will not conduct an electric charge well. Impure silicon is a semiconductor, meaning that it has some conductivity, or ability to conduct electricity.
The photons, or packets of light energy from the sun, hit the silicon surface and the energy frees electrons. If the silicon were pure, the energy needed to release any electrons would be too great for the solar panels to be useful.
Then, the electrons are drawn to an electric field that acts as a diode by forcing the electrons in a certain direction. The flow of electrons in a certain direction causes a current and the electric field causes voltage.
Together these aspects cause power that can be used for homes, satellites, and more.
Currently, solar cells harness a small percentage of the energy that they absorb, and many solar cells are needed to power a home or city.
Some researchers have suggested a new architecture for the cells. The improvements would aid in the management of the current to utilize more of the energy absorbed in the solar panels. The cost of this improvement is not yet known.
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