101 Battle of the Currents-Mid

Battle of the Currents FOCUS Question How did AC power become the main source of electricity in use today?

Let There Be Light! When you plug in your phone or play a game on your computer, you probably don't think about the electricity that charges up your devices. But in the late 1800s, a battle raged between inventors, and it determined how electricity powers our lives to this day. Have you heard of Thomas Edison? He invented the lightbulb. To power his lights, he developed a method of generating and moving electricity. His method was called direct current (DC). He thought the United States should be powered using direct current, and he fought to get his method accepted. Just what is direct current? Simply, it is the flow of electricity in one direction.

Edison and DC Edison used steam-powered generators to make DC electricity. Inside each generator, a coil of wire spun within a magnet. The coil of wire was attached to a device called a commutator. The commutator came in contact with two brushes, one with a positive charge. and one with a negative charge The rotating wire and commutator created an electrical current that flowed through the circuit from the positive to the negative brush. The result was a current that flowed steadily in one direction. Edison's power stations produced a steady flow of DC power with a constant force, or voltage But the DC electricity couldn't deliver power across a great distance. After about a mile, the DC flow lost power and fizzled out.

AC Paves the Way In 1884, inventor Nikola Tesla moved to the United States from Europe. He went to work for Thomas Edison. Tesla's job was to improve DC transmission. Instead, his solution was to design generators and motors that used alternating current (AC) —electricity that alternates, or moves back and forth, as it flows. Tesla's AC generators didn't require a commutator but instead used two rings. Current flowing from each ring resulted in electricity that moved in both directions. Tesla's generators cost less to operate than Edison's DC generators. The voltage of the AC current could be changed using transformers This doesn't work with DC. By raising the voltage, AC power could travel long distances from the power plant By lowering it again, the power was safer to use.

Electric Rivals Thomas Edison Thomas Alva Edison was born in Ohio and showed a love of learning from an early age. He started his own newspaper at age twelve! His next job, as a telegraph operator, sparked his love of technology. Before long. Edison was a full-time inventor. In 1880, he began the Edison Illuminating Company He believed that this company. would light the world. During his life. Edison earned patents for more than one thousand inventions. Nikola Tesla At home in Eastern Europe. Nikola Tesla had trouble finding people who were interested in his design for a new kind of motor. So he came to the United States and helped perfect AC technology. The system of generators and transmission lines used today is similar to the system Tesla invented in the late 1880s. Tesla had many ideas. and the money he made from his work on AC power financed some of his other projects.

Enter Westinghouse Edison rejected Tesla's idea for AC power. But a man named George Westinghouse saw the moneymaking potential of the AC system. He bought some of Tesla's patents and began designing a transmission system to send AC power far and wide. George Westinghouse was an inventor and businessman living in Pittsburgh, Pennsylvania He founded the Westinghouse company in 1886. He had seen examples of systems using AC in Europe. He believed the technology would work to deliver electricity throughout the United States. He built power stations in rural places that Edison's DC plants couldn't reach. Westinghouse also sold electricity at a low rate to gain business in cities.