Power is produced and distributed through three simple steps: generation, transmission, and distribution.
The first step, generation, is generally the same in every power plant. An energy source is used to turn a turbine and the turbine spins a generator. Generators are large magnets surrounded by coils of wire. When the magnet spins, a magnetic field passes along the wires, "pulling" electrons into a stream or current.
That process of producing electrical current is repeated from hydroelectric plants, to wind farms, to coal burning plants. All the plants use the same basic process, but they use different energy resources to get the generator spinning – like coal, wind, water, or even waste. There are exceptions to generator-driven power production. Solar power relies on devices called photovoltaic cells to convert light directly into electricity. Fuel cells are relatively new devices that use hydrogen as a fuel to produce electricity.
The second step is transmission. This is the process of getting the electricity to the users. Electricity is transmitted over a huge network of high-voltage lines called the grid. The grid is a system of transmission wires, substations, and transformers that make electricity accessible and usable. These lines crisscross our country, taking the power from the plants where it s produced, to the points where it is used. Next time you are out driving around, check out transmission lines. They are next to roads, over rivers, up on hills and down in valleys. Transmission lines are the long-distance leg of power’s trip from the plant, to the people.
The last step is distribution. Substations and transformers step the power down from the high-voltages used to transmit it over those long distances, to lower usable voltages. Then it is distributed over lower voltage lines into homes and businesses.
The current electrical distribution system relies heavily on this transmission grid. The problem is that the grid was not designed to carry the load it’s forced to carry. Increasing demand has outpaced updating the infrastructure, leaving a system vulnerable to outages and disruptions of service. In the future, the way electricity is distributed is very likely to change. Some industry experts predict a move toward "distributed generation." Instead of having large centralized power plants with large networks of transmission lines leading away from the generation source to the point of use, we could see smaller networks. These smaller networks would offer the ability to generate power to businesses and even homes.
Fuel cells, for instance, could be placed in the basement just like a furnace to generate electricity. For many computer-related businesses, on-site and backup generation is essential, because any interruption in power costs them big bucks. In the future, we may see small power plants, called microgeneration power stations. These microgeneration power plants would be small enough to fit into a neighborhood.
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