Revolution in the field: Tesla’s AC motor

At the age of 21,
with his invention of the AC motor, Tesla opened the door to a new era of
civilization. In 1895, $8 billion US dollars ($25bn in today’s
money) were invested in the first hydroelectric power plant in the world, at
Niagara Falls, marking the golden triumph of Tesla’s genius.

Drawing of Induction motorNikola Tesla Museum

As a student in Graz, Austria, Tesla dreamt of something magnificent that he called a rotating magnetic field.

At just 21 years old, he was convinced there must be a way to create more efficient, cost-effective and reliable motors.

The existing direct current motors were costly, complex in design and had a low power output.

One of the Original Induction MotorsNikola Tesla Museum

Tesla's AC motor was groundbreaking.

With its three main parts: a rotor, a stator and coils, this clever new system would convert electrical energy into mechanical energy with the use of the electro magnetic induction, i.e. magnetic field was being created with the use of alternating current.
Turning current into motion had never been done more efficiently before.

Induction motor with a disk rotorNikola Tesla Museum

The main innovative feature of Tesla’s design was its ability to transmit energy over great distances.

The system was a lot more cost-effective too.

Contract for commercial use of Tesla's discoveryNikola Tesla Museum

Although many showed disbelief in Tesla’s ideas, he was adamant about creating something magnificent – and he succeeded.

He signed the first contract for the commercial use of the AC motor that featured the rotating magnetic field in Strasbourg in 1883.

Tesla signed the contract in his native Cyrillic script.

Share CertificateNikola Tesla Museum

In search of commercial success for his discovery, Tesla traveled to America the following year.

Unfortunately Thomas Edison’s company had already invested substantially in the production and distribution of DC motors – the electric power system Tesla had intended to dislodge from the top spot.

Tesla's System: Motor and GeneratorNikola Tesla Museum

More fortunately, entrepreneur George Westinghouse realized the advantages of Tesla’s invention and bought the rights to use the AC system.

The AC/DC war had begun.

Tesla's System: Motor and GeneratorNikola Tesla Museum

Tesla's System Motor and GeneratorNikola Tesla Museum

Recognition at last

For the 400th anniversary of the discovery of America, Tesla and Westinghouse won a bid to light the entire World’s Columbian Exposition, held in Chicago in 1893, using Tesla’s revolutionary AC system.

Tesla's TurbopumpNikola Tesla Museum

Memorial Plaque from Niagara FallsNikola Tesla Museum

One of Tesla’s crowning triumphs was the fact that he owned nine of the thirteen patents used at the world’s first hydroelectric power plant, at Niagara Falls in 1896.

Interior of the Niagara Falls Plant RoomNikola Tesla Museum

The power generators at Niagara Falls were based entirely on Tesla’s invention.

The Original Piece of a Cable from the Niagara Falls plantNikola Tesla Museum

The hydroelectric power plant made its first transmission a remarkable 32 kilometers away to the city of Buffalo, New York State.

This event marked the beginning of the Second Industrial revolution.

Tesla with the representatives of the Westinghouse CompanyNikola Tesla Museum

According to Tesla himself, investments totaling $8 billion dollars ($25 billion in today’s money) were made in developing products based on his AC motor invention.

Robert Underwood Johnson and Nikola TeslaNikola Tesla Museum

Legacy to modern power

To this day, Tesla’s patented AC motor system is still used in the majority of electric motors.

Portrait of TeslaNikola Tesla Museum

His AC system is still the leading method for the production, transmission, distribution and utilization of the electrical energy.

Only the power of generators has increased.

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