Our Sun is one of the most surprising phenomena if we think about it. Light from the Sun basically travels millions of miles through space through our atmosphere and provides us with heat, visual light, and vital energy for plants. In essence, our Earth intercepts a quantity of solar energy equal to approximately 173 thousand terawatts. This is thousands of times more energy than is used by the planet's population, or to put it another way, one year of exposure to the sun contains double the energy we will ever get from all of Earth's non-renewable resources such as coal, oil , natural substances gas and uranium mined together. So, could it be possible that one day the world could be completely dependent on solar energy? Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay To answer the above question, we first need to look at how we can convert solar energy into electrical energy. Basically, the best source to convert the above energy is solar panels. Solar panels are made up of smaller units called solar cells. The most common solar cells are made of silicon, a semiconductor that is one of the most abundant elements on Earth. In a solar cell, crystalline silicon is sandwiched between conductive layers. Each silicon atom is connected to its neighbors by four strong bonds that essentially help the electrons stay in place so current can't flow. A silicon solar cell uses two different layers, namely N-type and P-type silicon. An N-type silicon has extra electrons while P-type silicon has extra spaces for electrons called holes. They basically form a PN junction, where electrons can wander across the PN junction leaving a positive charge on one side and creating a negative charge on the other. Sunlight carries the stream of tiny particles called photons. When one of these photons hits the silicon cell with enough energy, it can knock an electron loose from its bond, leaving a hole. Now, the negatively charged electron and the positively charged hole position are free to move. But due to the presence of electric field in the PN junction, the electron gets attracted to the N side while the hole gets attracted to the P side. Then, the mobile electrons are collected by thin metal fingers at the top of the cell. From there they flow through an external circuit before returning through the conductive aluminum foil on the back. Each silicon cell only puts out half a volt, but you can connect them together in modules to get more power. Twelve photovoltaic cells are enough to charge a mobile phone, while many more modules are needed to power an entire house. Solar cells can last for decades as electrons are the only moving parts in a solar cell and they all go back to where they came from. Please note: this is just an example. Get a custom paper from our expert writers now. Customize EssaySo, what stops us from being completely dependent on solar energy? There are physical and logistical challenges, and one of the most obvious of these is the uneven distribution of solar energy across the planet. Some areas are sunnier than others, so less energy is available on cloudy days or at night.