The grid is a complex system of power lines and transformers that connect electricity producers and consumers. Most local grids are interconnected for commercial and reliability reasons.
Our research has documented that women have limited access to electricity, especially in homes where men out-migrate. This article explores the social contexts that shape these patterns.
Like air and water, most people take electricity for granted. It powers the lights, appliances, and electronics that make our lives easier and more enjoyable, as well as providing heat and cooling for homes and businesses. Scientists and inventors have been deciphering the principles of electricity since the 1600s, with luminaries such as Benjamin Franklin, Thomas Edison, and Nikola Tesla making significant contributions to the field.
Traditionally, most electricity is generated at large power plants before it ends up in our homes and businesses. Power plants generate electricity using coal, natural gas, and other fuels to produce a high-voltage current. The current is sent over long distances by transmission lines to local facilities called substations. These facilities convert the high-voltage energy to lower voltages for distribution to residential, commercial, and industrial customers.
Electricity generation produces a number of environmental impacts, including air pollution from fossil-fuel combustion; discharges into water bodies (including thermal pollution); and land use for fuel storage and infrastructure. Learn more about these impacts on our centralized generation, distributed generation, and electricity delivery pages.
Electricity is transported from where it’s generated to homes and businesses through a network of power lines known as the transmission system. This “interstate highway” of electricity delivery moves bulk power over long distances, from power plants to facilities known as substations that are closer to areas with high demand for electricity. Consumers can recognize transmission lines by their taller poles or towers and multiple wires strung together. They operate at a much higher voltage level than electricity delivered to homes and businesses, which is reduced to lower voltage levels through transformers at the substations.
The word transmission has a broad meaning, from the passing of something from one place to another (like a radio or TV broadcast), to the spread of disease among people through heterosexual contact. It can also mean the conveyance of something, such as a vehicle’s transmission that uses belts and fluids to move the engine’s power to the wheels. 
The electricity that runs your household appliances makes its way from a power plant over miles of power lines and thousands of poles. It passes through a meter that keeps track of how much energy you use. Then it makes its way inside your home to the outlets and switches on walls throughout your house. It also goes through a breaker panel, such as this one, that controls the flow of power to your household appliances. The meter is a electromechanical device that is read by an employee of the electric distribution company when they visit to collect your monthly bill.
The power that runs your household is the result of a vast network of generating stations, power lines and substations that make up the U.S. electrical grid, or “grid.” The grid constantly balances supply and demand to ensure that there is always enough electricity to meet your needs. It is a complex and enormous system that is out of sight to most, but comes into focus when there is a major disruption such as a blackout.
At a centralized power plant, electricity is produced by huge generators that use fuel like coal, natural gas and wind to produce the current that travels through transmission lines. These lines are heavy cables strung between tall towers, and the system of high voltage transmission networks allows large amounts of electricity to be moved across long distances. Power moves from the transmission lines to local facilities called substations where the voltage is reduced.
This reduced voltage is then sent over the distribution system to your neighborhood. The power may travel on power lines that are either on poles or sitting on the ground (these are called pad mount transformers). At the local level, the electricity is transferred to smaller distribution wires that run through your neighborhood and then to your home. Smaller transformers again reduce the voltage to a safe level for your household use.
Whether the power is coming from a radial or network system, the end users are connected through a service drop (the name varies from region to region) which connects to a service mast and a main lateral. Usually, a secondary mast is located nearby and the lateral connects to a pole at your home or business.
The final use of electricity involves end-use consumers consuming energy for heating, cooling and lighting as well as the operation of appliances, electronics, and machinery. Residential, commercial, and industrial sectors consume about one-third of all OECD electricity consumption. The transportation sector, which is dominated by road transport, only consumes a small fraction of electricity, but this could increase as electric vehicles become more widespread.
In homes, electric consumption is measured by a household’s meter and recorded in kilowatt hours (kWh). This includes all the energy needed to run household appliances and electronic devices. It’s also important to consider the simultaneity of these loads, how many appliances are in use at a given time. This is known as load profile, and the more load is present at a single instant, the greater the demand.
As electricity is consumed, it travels over long distances across high-voltage transmission lines to local facilities called substations. These transform the power to a lower voltage and distribute it to nearby households and businesses through distribution networks. It’s also used for telecommunications, making it possible to send messages around the world in minutes. Electricity’s early application in this area, through the electrical telegraph in the 1860s, revolutionised communication systems, and continues to play an essential role today. It is also seen as a key technology for decarbonising sectors such as transport and industry, replacing traditional fossil fuels with low-carbon sources.