Solar Powered Housing
With the increasing energy consumption rates and increasing pollution rates as a result, it is important for our society to focus on cleaner, more renewable energy sources. Because households are a major consumer of energy throughout the world, families could contribute greatly to the use of renewable energy sources through the use of solar home systems. If more and more people agree to the use of solar home systems, our fossil fuel consumption rates will drop and we will notice profound improvements throughout our environment. This essay will discuss various topics that are necessary in order to understand the function of a solar home system.
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They consist of two differently charged surfaces, usually made of silicon, a metallic grid that connects the two surfaces together, an antireflection coating, and a protective glass cover. To create the electric current, the cells take advantage of the fact that light can knock electrons out of the atoms of certain substances. To make this happen, the cells first absorb the photons from the sunlight they are exposed to. These photons then cause the electrons from the positively charged surface to bounce to the negatively charged surface creating an electric current. This direct current is then carried by wires away from the photovoltaic cells and through an inverter that transforms the current into an alternating current so it can be used in the house (U.S. Department of Energy).
There are two different types of silicon cells that can perform this function; thin-film and crystalline. Thin-film cells are generally less expensive but are also less efficient and don’t last as long. They tend to have a 10% efficiency rate for converting sunlight to electricity. Crystalline cells, on the other hand, are more expensive but have increased efficiency and durability. They tend to have a 20% efficiency rate for converting sunlight into electricity. Even more efficient cells (40%) are in the process of being developed, however, are currently too expensive for typical use (Architectural Record).
Each individual cell tends to be very small and produces only a small amount of energy. These cells are therefore combined together to form modules or panels that can produce anywhere from a few milliwatts to several megawatts of energy. These modules are measured in terms of “peak watts”. This refers to the maximum output of the module under peak sun condition or conditions where sunlight gives off 1000 watts of energy per square meter. “Sun hours” or “insolation”, refers to the number of hours an area experiences peak sun conditions. In North America, we average about 3 to 4 peak sun hours per day in the summer. Equatorial regions can average above 6 peak sun hours per day. Consequently, the benefit and efficiency of a solar home system is greatly determined by the area in which it is being used (Advanced Energy Group).
There are many different parts to a solar home system. A basic solar home system will include a PV module, a charge controller, a battery, an inverter, wiring, fluorescent lights, and outlets for other appliances. The first part, the module, must be orientated appropriately to absorb the most amount of sunlight. The most efficient orientation for North American users is direct south. This allows the module to absorb light throughout the day. To determine true south, you can divide the span of time between sunrise and sunset and true south is the position of the sun at that time. The angle of the module should be set anywhere from the degree of your latitude to plus or minus 15 degrees depending on when you consume...