Supplement to The Future of Electricity “The Grid Grows Up”
ELECTRIFYING THE NATION
Before the end of the 19th century, electric power changed from a curious novelty into something useful very quickly. Cities were the first places to develop electric power companies that could generate and distribute electricity to customers. The first electric power grid as we know it served a part of New York City in 1888.
But those first electric systems were tiny by today’s standards. One early transmission line carried just 220 volts –that’s the same amount of electricity that flows through the cord connecting a clothes dryer to a household electric outlet today. Those early power lines didn’t cover very long distances, either. The first electric utility systems were often geographically isolated, serving just one town or distinct small sections of a city.
During those early decades, engineers made some decisions about electricity that are still with us. Before the end of the 1800s, engineers agreed that using alternating current (AC) was better than direct current (DC) to move electricity through the expanding power grids in cities. With the technology they had available and the distances they were covering, that decision made good economic sense. Today’s power grid is almost entirely an AC system.
A lot of the electricity for those early widely separated electric grids in cities first came from large reciprocating engines that took up a lot of room to produce very small amounts of electricity. Then early in the 20th century, Charles Curtis invented the first practical steam turbine that could generate large quantities of electricity in a much smaller space. His new machine, a giant leap forward in 1903, generated 5,000 watts. It continued to produce electricity for customers in Newport, Rhode Island, until 1927.
Today, just one modern steam turbine can generate a thousand times more electricity—but the basic design for a 21st-century steam turbine uses the same technology invented more than 100 years ago.
By the late 1920s, America’s big cities and many medium-sized small towns had generating plants and electric power grids serving their local areas. But municipal governments and investor-owned electric utility companies didn’t want to extend their electric grids into rural areas with only a few customers per mile of line.
Then, in 1935, President Franklin Roosevelt signed an executive order that led to the formation of the Rural Electrification Administration (REA). That set in motion an army of civic-minded farmers and community leaders in rural areas. They formed cooperatives to bring the benefits of electricity to the sparsely populated parts of our country. During that same decade, investor-owned utilities (IOUs) were also expanding their systems. It was also an era that launched major construction projects such as the Hoover Dam and the Tennessee Valley Authority with massive river dams containing hydroelectric power plants.
Less than 20 years later, by the mid-1950s, a vast new system of power plants, transmission lines, and distribution lines had been completed, bringing electricity to electric meters in almost every county of America. Building an electricity network as big as all America took billions of dollars to accomplish. And it’s kept right on growing.
America’s power grid is a vast infrastructure worth more than 1 trillion dollars. Some of it is owned by investors (the stockholders of big corporations), some of it by government units, and much of it is owned by the members of electric co-ops. Today’s grid includes many millions of electric meters, about 5.5 million miles of distribution lines, plus more than 200,000 miles of high-voltage transmission lines that carry electricity from hundreds of generating stations. Altogether, those power plants have a total generating capacity of about 1 million megawatts.
To read the June 2009 Future of Electricity column that goes along with this supplement, go to The Grid Grows Up.