How Power Grids Work

How power grids transfer power from power plants through power lines and transformers and finally into our homes and businesses.

Power grids are a common sight in America. If you look out your window, you can usually see the power cables that are attached to different houses or buildings in your neighborhood. If you have ever been on a long road trip, you have seen the high voltage power lines that are strung up to the enormous towers that cross the distances between the populated areas. These enormous power cables are connected to plants that generate power, and they distribute the power to communities throughout the nation. This system of distributing power through cables is called a power grid.

An electrical power grid allows electricity to flow from a power generation source to the public. Power can be sent from a power plant across the country through the power grid system. Power is also sold from one country to another through the power grid system. This amazing series of connectors and relays ensures that people even in the most remote areas of the country are able to have power for lighting, heating, air conditioning, and other means.

Power is produced by creating a force to spin a large electric generator. The generator produces electricity which is then transferred into the power grid system. These generators are powered through many different sources. In damns, water is used to spin the wheels. Many are spun by steam power generated by nuclear power, or by burning coal or gas. There are also several less common methods of producing power.

Twenty-five percent of the power in the United States is produced by hydro-electrical power in damns. The engineers that designed the large damns in the country have created ways to harness the enormous power of the water running through the dams to turn massive electric generators. Power created by the force of water is referred to as hydroelectric power.

Nuclear reactors use the power of a nuclear reaction to create steam. This steam is then pressurized and used to turn electric generators. Nuclear power generation has fallen out of favor in the United States and is rarely used today. This is because of the waste left over when producing the power.

The burning of coal or natural gas to produce power has become the fastest growing method of power production. These two methods utilize steam power to turn generators. Due to an increase in the need for power, the United States and other countries have begun to look for more natural gas and coal to fuel power facilities. The United States is currently in the process of planning the construction of a natural gas pipeline from Alaska that could provide enough fuel to run the current natural gas energy plants for the next one hundred years.



Alternative methods of producing power are also available. Some plants use diesel or gasoline engines to spin their electric turbines. Other areas of the country harness the wind or sun by constructing windmills and solar panels. Regardless of how the power is produced, all of these production plants and facilities are hooked into the national power grid. Their power is then transferred through high voltage transmission lines to a control center.

The first place that the power is transferred to is the control center. There are over 100 control centers in the United States. These control centers transfer power to different regions or areas. The control facilities are run by experts who monitor the needs of the different areas and regions under their control. They transfer power from areas of low demand to areas of high demand to ensure that all areas have the power that they need to operate. Usually the power switch is transferred by simply flipping a switch which automatically transfers the power.

Power transferred out of the control center goes to substations. These substations can be either regional or in residential neighborhoods, depending on the amount of people in an area. Before the electricity can be delivered to a community to be used in homes and businesses, it is necessary to reduce the current. This reduction of the current is referred to as "stepping down" the current. After the current is stepped down at the substation it is pumped into power lines.

These power lines are the lines that crisscross through almost every modern community.

Even though the power has been stepped down, the power in these lines is still too powerful to be used in a house or business. The power is stepped down once or several more times as it branches out into the community when it passes through additional substations or small transformers.

The power grid that delivers our power does not store power within the system. The power plants produce exactly the amount of power that is needed in the community. Millions of miles of power lines ensure that the power is delivered to the right place at the right time. This method usually works well, but when there is an unexpected high demand in one location the system may not be able to handle the needs and may overload.

When one piece of the system fails due to an overload, then it will affect the rest of the system. This is because the other parts of the system have to make up for the sudden lack in power. If the substation, power station, transformer, or any other part of the power system cannot handle the new surge of power then they will also fail. This chain reaction can result in the blackout of a large region of the power grid.

After a damaged system has been repaired, technicians cannot start it back up immediately. Bringing the entire system back online at once could overload the system again and result in another blackout. In order to avoid this problem, the system is started up in steps to ensure that there is no power surge through the system.

The power grid system is an amazing piece of technology. The power companies produce just the right amount of energy to supply power to cities hundreds and sometimes thousands of miles away. This power is distributed so efficiently most of the time that we take it for granted. However, every time we turn on a light we are transferring power from the grid. When this happens the entire grid compensates for our small use of power.

© High Speed Ventures 2011