What is the electric grid? Most of us don't give a second thought to where our electricity comes from. The truth is that the power grid is the biggest engineering achievement of the 20th century and one of the most indispensable machines on Earth.
Every day, the grid powers our lives in amazing ways.
What powers the light behind your screen? Keep scrolling to find out!
RELIABLE POWER PROVIDES THE FOUNDATION FOR MODERN LIFE Natural gas, nuclear, and coal power plants produce 86 percent of the electricity needs of the U.S. These plants can run continuously, and they can be built just about anywhere. On-demand electricity powers everything from our favorite electronics and the Internet to air conditioners and modern factories.
About 7,000 power plants nationwide generate the power we use in our homes, offices, hospitals, schools, factories, etc.
Natural gas, nuclear, and coal power plants make it possible to meet customers' electricity demands on a second-by-second basis. Each of these plants can run reliably, and natural gas plants in particular can increase or decrease their output to follow changes in electricity demand.
UNRELIABLE POWER MAKES BLACKOUTS MORE LIKELY Wind and solar installations provide about 4 percent of our electricity. These plants are unreliable because their output depends on whether the wind is blowing or the sun is shining. With increasing production from wind and solar plants, grid operators struggle to keep electricity supply and demand in balance. When supply can't keep up with demand, the grid becomes unreliable and whole regions can experience blackouts.
Solar plants generated just 0.3 percent of the power in the U.S. in 2013 despite millions of dollars from taxpayers and mandates that require the use of solar in some places.
There are over 46,000 wind turbines in the U.S. Collectively, those turbines generated 4.1 percent of our power in 2013.
The amount of power put on the grid by wind and solar plants fluctuates throughout the day and night and can impact grid reliability directly. Over time, high subsidies for wind and solar generation also undermine the grid indirectly, by forcing coal and nuclear plants to close early. If those plants close early, there is no backup source to cover the times when there isn't enough wind or sun.
HIGH-VOLTAGE TRANSMISSION LINES CARRY POWER FROM GENERATORS TO LOCAL DISTRIBUTION NETWORKS To minimize power loss, after the electricity leaves the power plant, it is "stepped up" at substations to high voltage and then moved long-distance across transmission lines to get where it is needed. Behind the scenes, the transmission grid is kept in balance by trained grid operators who monitor this flow of electricity and ensure that supply matches demand every second of the day.
It's all about balance! Electricity is very difficult and expensive to store or save for later use, so electricity demand must be matched by supply instantaneously. If supply and demand fall out of sync, the voltage on the grid will rise or fall, causing equipment damage or even blackouts.
HOW DOES ELECTRICITY REACH YOU? Step-down transformers lower the voltage of electricity coming from the transmission grid, and distribution lines take the power to your home or business. Small transformers commonly seen on utility poles step the voltage down again to levels that are safe for your home wiring and appliances.
The electricity that reaches your home travels over a very complex and expensive infrastructure. From 2001 through 2010, yearly investment in generation, transmission, and distribution averaged $62.9 billion.
THE ELECTRIC GRID POWERS OUR LIVES Reliable, affordable power is nothing short of an everyday miracle. We use it to power our homes, businesses, schools, and hospitals. It literally lights up our lives and makes our modern-day conveniences possible.
In 2013, people in the U.S. used over 4 million megawatt-hours of electricity to power their lives.
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