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The Wardenclyffe Power Plant intended by Nikola Tesla to be a "World Wireless" telecommunications facility.
The World Wireless System was a turn of the 19th century proposed communication and electrical power delivery system designed by the inventor Nikola Tesla based on his theories of using the Earth and/or the Earths atmosphere as an electrical conductor. Tesla claimed this system would allow for "the transmission of electric energy without wires" on a global scale[1] as well as point-to-point wireless telecommunications. He made public statements citing various schemes to accomplish this from the mid-1890s on. By the end of 1900 Tesla had convinced banker J. P. Morgan to finance the construction of a wireless station (eventually sited at Wardenclyffe) based on his ideas intended to transmit messages across the Atlantic to England and to ships at sea. Almost as soon as the contract was signed Tesla decided to scale up the facility and add his ideas of wireless power transmission to better compete with Guglielmo Marconi's radio based telegraph system. Morgan refused to fund the changes and, when no additional investment could be found, the project at Wardenclyffe was abandoned in 1906, never to become operational.
During this period Tesla filed numerous patents on the basic functions of his system including transformer designs, transmissions schemes, tuning circuits, and methods of signaling. He also described his plan to have 30 Wardenclyffe style towers around the world that would be tied into existing telephone and telegraph systems. Tesla would continue to elaborate to the press and in his writings for the next few decades on his system's capability's and how it was superior to radio based systems.
Despite Tesla's claims that he had "carried on practical experiments in wireless transmission"[2] there is no evidence Tesla ever transmitted power beyond laboratory-scale distances and most modern scientific opinion is that his wireless power scheme would not have worked.
History
Origins
Tesla's idea's for a world wireless system grew out of experiments he begun in the early 1890s after he learned of Hertz's experiments with electromagnetic waves using coils and spark gaps.[6][7] He duplicated those experiments and went on to develop various alternator apparatus and developed his own very large air-gapped coil, known now as a Tesla coil.[8][9] Tesla's primary interest in wireless phenomenon was as a power distribution system, early on pursuing wireless lighting.[10] From 1891 on Tesla was delivering lectures including "Experiments with Alternate Currents of High Potential and High Frequency" in 1892 in London and in Paris and went on to demonstrate "wireless lighting"[11] in 1893[12] including lighting Geissler tubes wirelessly.One-wire transmission
The first experiment was the operation of light and motive devices connected by a single wire to one terminal of a high frequency induction coil, performed during the 1891 New York City lecture at Columbia College. While a single terminal incandescent lamp connected to one of an induction coil’s secondary terminals does not form a closed circuit “in the ordinary acceptance of the term”[13] the circuit is closed in the sense that a return path is established back to the secondary by capacitive coupling or 'displacement current'. This is due to the lamp’s filament or refractory button capacitance relative to the coil’s free terminal and environment; the free terminal also has capacitance relative to the lamp and environment.Wireless transmission
The second result demonstrated how energy can be made to go through space without any connecting wires. The wireless energy transmission effect involves the creation of an electric field between two metal plates, each being connected to one terminal of an induction coil’s secondary winding. A gas discharge tube) was used as a means of detecting the presence of the transmitted energy. Some demonstrations involved lighting of two partially evacuated tubes in an alternating electrostatic field while held in the hand of the experimenter.[14]In his wireless transmission lectures Tesla proposed the technology could include the telecommunication of information.
Development
Drawing from the 1897 U.S. Patent 649,621, "Apparatus for Transmission of Electrical Energy" showing Tesla's idea of transmitting electrical energy through the upper atmosphere via balloons tethered at 30,000 feet.
Tesla (like many scientists of that time[15]) thought, even if radio waves existed, they would probably only travel in straight lines making them useless for long range transmission. He theorized that transmitting electrical signals any distance would have to use the planet Earth or some other medium to overcome this limitation.[16] By the end of 1895 he was making statements to the press on the possibility that "the earth's electrical charge can be distributed, and thereby electrical waves efficiently transmitted to any distance without the use of cables or wires" to transmit "intelligible signals" and "motive power".[17] In April 11, 1896 Tesla made another statement that he believed that "messages might be conducted to all parts of the globe simultaneously" using electric waves "propagated through the atmosphere and even the ether beyond".[18] In September of 1897 he applied for a patent[19] on a wireless power transmission scheme consisting of transmitting power between two tethered balloons maintained at 30,000 feet, an altitude where he thought a highly conductive layer would exist.
Between 1895 - 1898 Tesla constructed a large coil in his New York City lab called a magnifying transmitter to test his earth conduction theories.[20] In 1899 Tesla conducted large scale experiments at Colorado Springs, Colorado. From his measurements there he concluded the Earth was "literally alive with electrical vibrations." He noted that lightning strikes seemed to show the Earth was indeed a big conductor with the waves of energy from each strike going from one side of the Earth to the other. At Colorado Springs he also constructed a large magnifying transmitter measuring fifty-one feet (15.5 m) in diameter which could develop a working potential estimated at 3.5 million to 4 million volts and was capable of producing electrical discharges exceeding one hundred feet (30 m) in length.[21] With it he tested earth conduction and lit un-connected electric lights outside his lab in a demonstration of wireless power transmission at relatively short ranges.
After Tesla returned to New York City from Colorado Springs in 1900 he sought venture capitalists to fund what he thought was revolutionary wireless communication and electric power delivery system using the Earth as the conductor. At the end of 1900 he gained the attention of financier J. P. Morgan who agreed to fund a pilot project (later to become the Wardenclyffe project) which, based on Tesla's theories, would be capable of transmitting messages, telephony, and even facsimile images across the Atlantic to England and to ships at sea. Morgan was to receive a controlling share in the company as well as half of all the patent income. Tesla's decision in July 1901 to scale up the facility and add his ideas of wireless power transmission to better compete with Guglielmo Marconi's new radio based telegraph system was met with Morgan's refusal to fund the changes.
Construction on the Wardenclyffe "wireless plant" in Shoreham started towards the end of 1901 and continued for the next 3 years. The plant included a Stanford White designed 94 by 94 ft (29 by 29 m) brick building, a wood-framed tower 186 feet (57 m) tall with a 68 feet (21 m) in diameter "cupola" on top, and a 120 feet (37 m) shaft sunk into the ground with sixteen iron pipes driven 300 feet (94.4 m) horizontal from the shaft in order for the machine, in Tesla's words, "to have a grip on the earth so the whole of this globe can quiver."[24][25] Funding problems continued to plague Wardenclyffe and by 1905-1906 most of the site's activity had to be shut down.
Elements
Tesla basic patent drawing for the grounded resonant transformer used at Wardenclyffe
U.S. Patent 1,119,732
U.S. Patent 1,119,732
Through the latter part of the 1890s and during the construction of Wardenclyffe Tesla applied for many patents covering the elements that would make up his wireless system. The system Tesla came up with was based on electrical conduction with an electrical charge being conducted through the ground and being returned through the air.[26] It consisted of a grounded Tesla coil as a resonance transformer transmitter that he theorized would be able to create a displacement of Earth's electric charge by alternately charging and discharging the oscillator's elevated terminal. This would work in conjunction with a second coil at a distant location with the grounded helical resonator of that Tesla Coil and an elevated terminal used in receive mode.[27][28][29] Tesla believed that the placement of a grounded resonance transformer at another point on the Earths surface in the roll of a receiver tuned to the same frequency as the transmitter would allow electric current flowing through the Earth between the two. He also believed waves of electric current from the sending tower would reflect back from the far side of the globe, resulting in amplified stationary waves of electric current that he could direct to any point on the globe, localizing power delivery directly to the receiving station. The other part of his system was electricity returned via "an equivalent electric displacement""[30] in the atmosphere via a charged conductive upper layer that Tesla thought existed,[26] a theory dating back to an 1872 idea for a proposed wireless power system by Mahlon Loomis.[31] The current could be used at the receiver to drive electrical devices.[28]
Tesla told a friend his plans included the building of more than thirty transmission-reception stations constructed near major population centers around the world[32] with Wardenclyffe being the first. If plans had moved forward without interruption the Long Island prototype would have been followed by a second plant built in the British Isles, perhaps on the west coast of Scotland near Glasgow. Each of these facilities would include a large magnifying transmitter of a design loosely based upon the apparatus assembled at the Colorado Springs experimental station in 1899.[33]
Claimed applications
Tesla description of his wireless transmission ideas in 1895 included its humanitarian uses in bringing electricity to remote parts of the world and fostering greater communications amongst nations.[34] His June, 1900 Century Magazine article "The Problem of Increasing Human Energy" included photographs of his Colorado Springs experiments and his thoughts on how Hertz experiments were not "an experimental verification of the poetical conceptions of Maxwell". He elaborated on his system of using the Earth as the medium for communication and power delivery. He wrote how he could set up communication at any distance. He noted his system would localize electrical delivery to a point on the globe via stationary waves. He also noted this same process could be used to locate objects such as icebergs or ships at sea.
In 1909 Tesla stated:
- "It will soon be possible, for instance, for a business man in New York to dictate instructions and have them appear instantly in type in London or elsewhere. He will be able to call up from his desk and talk with any telephone subscriber in the world. It will only be necessary to carry an inexpensive instrument not bigger than a watch, which will enable its bearer to hear anywhere on sea or land for distances of thousands of miles. One may listen or transmit speech or song to the uttermost parts of the world."[35][36]
Tesla elaborated on his world wireless system in his 1919 Electrical Experimenter article titled "The True Wireless", detailing its ability for long range communication and putting forward his views that radio based communication could not possibly work as theorized.[37][38]
Feasibility
Although Tesla demonstrated wireless power transmission at Colorado Springs, lighting electric lights mounted outside the building where he had his large experimental coil,[39] and would make claims afterwards that he had "carried on practical experiments in wireless transmission"[40] he did not scientifically test his theories. He believed he had achieved Earth resonance at Colorado Springs which, according to his theory, would work at any distance.[41] There is no evidence Tesla ever transmitted power beyond these laboratory-scale distances[23][42][43][44][45][46][47][48][49] and most modern scientific opinion is that his wireless power scheme would not have worked.[42][43][47][49][50][51][52][53][54]Related patents
- SYSTEM OF ELECTRIC LIGHTING, April 25, 1891, U.S. Patent 454,622, June 23, 1891.
- MEANS FOR GENERATING ELECTRIC CURRENTS, August 2, 1893, U.S. Patent 514,168, February 6, 1894.
- ELECTRICAL TRANSFORMER, March 20, 1897, U.S. Patent 593,138, November 2, 1897.
- METHOD AND APPARATUS FOR CONTROLLING MECHANISM OF MOVING VESSEL OR VEHICLES, July 1, 1898, U.S. Patent 613,809 November 8, 1898.
- SYSTEM OF TRANSMISSION OF ELECTRICAL ENERGY, September 2, 1897, U.S. Patent 645,576, March 20, 1900.
- APPARATUS FOR TRANSMISSION OF ELECTRICAL ENERGY, September 2, 1897, U.S. Patent 649,621, May 15, 1900.
- METHOD OF INTENSIFYING AND UTILIZING EFFECTS TRANSMITTED THROUGH NATURAL MEDIA, June 24, 1899, U.S. Patent 685,953, November 5, 1901.
- METHOD OF UTILIZING EFFECTS TRANSMITTED THROUGH NATURAL MEDIA, August 1, 1899, U.S. Patent 685,954, November 5, 1901.
- APPARATUS FOR UTILIZING EFFECTS TRANSMITTED FROM A DISTANCE TO A RECEIVING DEVICE THROUGH NATURAL MEDIA, June 24, 1899, U.S. Patent 685,955, November 5, 1901.
- APPARATUS FOR UTILIZING EFFECTS TRANSMITTED THROUGH NATURAL MEDIA, March 21, 1900, U.S. Patent 685,956, November 5, 1901.
- METHOD OF SIGNALING, July 16, 1900, U.S. Patent 723,188, March 17, 1903.
- SYSTEM OF SIGNALING, July 16, 1900, U.S. Patent 725,605, April 14, 1903.
- ART OF TRANSMITTING ELECTRICAL ENERGY THROUGH THE NATURAL MEDIUMS, May 16, 1900, U.S. Patent 787,412, April 18, 1905.
- ART OF TRANSMITTING ELECTRICAL ENERGY THROUGH THE NATURAL MEDIUMS, April 17, 1906, Canadian Patent 142,352, August 13, 1912.
- APPARATUS FOR TRANSMITTING ELECTRICAL ENERGY, January 18, 1902, U.S. Patent 1,119,732, December 1, 1914.
