Wireless Transmission of Electricity

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1 Wireless Transmission of Electricity Yugant A.Parate 1, Pranav D.Chauhan 2 1 Department of ElectricalEngineering, Sardar Patel College of Engineering, India 2 Department of Electrical Engineering,Sardar Patel College of Engineering, India ABSTRACT Power Crisis is one of the biggest problems of 21 st century. We can t even survive without electricity. Due to this we have to think about renewable source of energy. Renewable energy sources such as solar,wind,hydro etc are available abundant in nature but their initial cost is high. Also transmission of electricity over long distances causes large transmission losses; the current transmission system is 70-74% efficient i.e.30-26% of electricity is wasted for transmission of electricity. And also it is very costly. So to overcome such problems one can think for Wireless Transmission of electricity. This paper studies the possibility and development of wireless transmission by discussing mainly three technologies as:- 1) Tesla Theory 2) Microwave power transmission (MPT) called solar power satellite 3) Fiber Laser Technology Key Words: Microwave Power transmission (MPT), Nikola Tesla, Tesla theory, Fiber laser technology. 1. INTRODUCTION We see the world is going wireless day by day, iphone and blackberry phones makes PC applications wireless and 4G,Wi-Max technologies will make it even faster.in that manner electricity distribution seems to be outdated with big wires.so there is a need of wireless transmission of electricity. In our current distribution system there are large losses and the low efficiency, we waste more than half of its resources. While distributing power from power station generators to the consumer, the resistance of the wire used in the electrical grid distribution system causes a loss of 26-30% of the energy generated. So to overcome this and keeping the power system synchronous with the modern technologies, we have to replace the current distribution system with the efficient one. So transmission of power without wires may be one noble alternative for electricity transmission. Figure.The 187-foot Wardenclyffe Tower (Tesla Tower) 2. TESLA THEORY In this remarkable discovery of the "True Wireless" and the principles upon which transmission and reception, even in the present day systems, based, are proposed by Dr. Nikola Tesla,shows us that he is indeed the "Father of the Wireless." The most well known and famous Wardenclyffe Tower (Tesla Tower) was designed and constructed mainly for wireless transmission of electrical power. Nikola Tesla began planning the Wardenclyffe Tower facility ca. 1898, and in 1901, construction began on the land near Long Island Sound. Architect Stanford White designed the Wardenclyffe facility main building. This was the first step towards a practical wireless system. The wireless energy transmission effect involved the creation of an electric field between two metal plates, each being connected to one terminal of an induction coil s secondary winding. Once again, a ISSN: Page 92

2 light-producing device (in this case a gas discharge tube) was used as a means of detecting the presence of the transmitted energy. "The most striking result obtained" involved the lighting of two partially evacuated tubes in an alternating electrostatic field while held in the hand of the experimenter. While working Sir Tesla went on to develop two theories related to these observations, which are:- i)by using two type-one sources positioned at distant points on the Earth s surface, it is possible to induce a flow of electrical current between them. ii)by incorporating a portion of the Earth as part of a powerful type-two oscillator the disturbance can be impressed upon the Earth and detected at great distance, or even all over the surface of the globe. Tesla also made the assumption that the Earth is a charged body floating in space. Tesla clearly specified the Earth as being one of the conducting media involved in ground and air system technology. The other specified medium is the atmosphere above 5 miles (8.0 km) elevation. While not an ohmic conductor, in this region of the troposphere and upwards, the density or pressure is sufficiently reduced to so that, according to Tesla s theory, the atmosphere s insulating properties can be easily impaired, allowing an electric current to flow. His theory further states that the conducting region is developed through the process of atmospheric ionization, in which the effected portions thereof are changed to plasma. 3. THE MICROWAVE POWER TRANSMISSION (MPT) It is also called as Solar power satellitewilliam C. Brown, the leading authority on wireless power transmission technology, has loaned this demonstration unit to the Texas Space Grant Consortium to show how power can be transferred through free space by microwaves. A block diagram of the demonstration components is shown below. The primary components include a microwave source, a transmitting antenna, and a receiving rectenna. The microwave source consists of a mi %) and high power handling capability. A rectifying antenna called a rectenna receives the transmitted power and converts the microwave power to direct current (DC) power. This demonstration rectenna consists of 6 rows of dipoles antennas where 8 dipoles belong to each row. Each row is connected to a rectifying circuit which consists of low pass filters and a rectifier. The rectifier is a Ga AsSchottky barrier diode that is impedance matched to the dipoles by a low pass filter. The 6 rectifying diodes are connected to light bulbs for indicating that the power is received. The light bulbs also dissipated the received power. This rectenna has a 25% collection and conversion efficiency, but retinas have been tested with greater than 90% efficiency at 2.45 GHz. The transmission of power without Fig 1: The figure demonstrates the wireless power transfer process through microwaves. wires is not a theory or a mere possibility, it is now a reality. The electrical energy can be economically transmitted without wires to any terrestrial distance, many researchers have established in numerous observations, experiments and measurements, qualitative and quantitative [5-9]. These have demonstrated that it is practicable to distribute power from a central plant in unlimited amounts, with a loss not exceeding a small fraction of one per cent, in the transmission, even to the greatest distance, twelve thousand miles - to the opposite ISSN: Page 93

3 end of the globe. This seemingly impossible feat can now be readily performed by electrical researchers familiar with the design and construction of my "high-potential magnifying transmitter," There were three popular theories present in the literature of the late 1800's and early 1900's. They were: 1. Transmission through or along the Earth, 2. Propagation as a result of terrestrial resonances 3. Coupling to the ionosphere using propagation Diagram showing the transmitting & receiving circuit For the transmission & reception of electric power by wireless Fig. Two optical forms of wireless antennae formed of search light beam- ionized atmospheric streams. It has been proven that electrical energy can be propagated around the world between the surface of the Earth and the ionosphere at extreme low frequencies in what is known as the Schumann Cavity. Knowing that a resonant cavity can be excited and that power can be delivered to that cavity similar to the methods used in microwave ovens for home use, it should be possible to resonate and deliver power via the Schumann Cavity to any point on Earth.. The intent of the experiments and the laboratory Tesla had constructed was to prove that wireless transmission of Electrical power was possible. Although Tesla was not able to commercially market a system to transmit power around the globe, modern scientific theory and mathematical calculations support his contention that the wireless propagation of electrical power is possible and a feasible alternative to the extensive and costly grid of electrical transmission lines used today for electrical power distribution. Power transmission system using directional ultrasound for power transmission includes a transmitting device and areceiving device. The transmitting device has a set of ultrasound transducers forming an ultrasound transducer array, wherein the array is a set of spaced individual placed in the X-Y plane disposed to generate an ultrasound beam in the Z direction.another possibility is to use highly efficient fiber lasers for wireless power transmission where the possibilities are similar to microwaves concept but lasers emit energy at frequencies much higher that microwaves. For several years NASA, ENTECH, and UAH have been working on various aspects of collection of the laser radiation And conversion to electrical power for laser wireless power transmission. Fig.: Laser energy used to power a model airplane with solar cells. Source 4. LASER With a laser beam centered on its panel of photovoltaic cells, a lightweight model plane makes the first flight of an aircraft powered by a laser beam inside a building at NASA Marshall Space Flight Center. In the case of electromagnetic radiation closer to visible region of spectrum (10s of microns (um) to 10s of nm), power can be transmitted by converting electricity into a laser beam that is then pointed at a solar cell receiver. This mechanism is generally known as "Power Beaming" because the Power is Beamed at a receiver that can convert it to usable electrical energy. There are quite a few unique advantages of Laser based energy transfer that outweigh the disadvantages ]. ISSN: Page 94

4 1.Collimated monochromatic wave front 3.Airy disk (on how most fundamentally propagation allows narrow beam cross-section area wavelength dictates the size of a disk with distance) for energy confinement over large ranges. 4.Applications of laser diodes (on how the laser 2.Compact size of solid state lasers photovoltaic s sources are utilized in various industries and their semiconductor diodes allows ease of integration sizes are reducing for better integration) into products with small form factors. transfer of energy especially for Space and Lunar 3.Ability to operate with zero radio-frequency missions. interference to existing communication devices i.e. NASA's Dryden Flight Research Center has wi-fi and cell phones. demonstrated flight of a lightweight unmanned 4.Control of Wireless Energy Access, instead of model plane powered by a laser beam. Thisproofof-concept unidirectional transfer where there can be no demonstratethe feasibility of periodic authentication before transferring energy. recharging using the Laser beam system and the.its drawbacks are: lack of need to return to ground. 1.Conversion to light, such as with a laser, is 5. ECONOMIC IMPACT moderately inefficient (although quantum cascade The concept looks to be costly initially. The lasers improve this) investment cost of Tesla Tower was $150,000 2.Conversion back into electricity is moderately (1905). In terms of economic theory, many inefficient, with photovoltaic cells achieving 40%- countries will benefit from this service. Only 50% efficiency.(note that conversion efficiency is private, dispersed receiving stations will be needed. rather higher with monochromatic light than with Just like television and radio, a single resonant insulation of solar panels). energy receiver is required, which may eventually 3.Atmospheric absorption causes losses. As with be built into appliances, so no power cord will be microwave beaming, this method requires a direct necessary! Monthly electric utility bills from oldfashioned, line of sight with the target. fossil-fuelled, loss prone electrified The Laser "Power Beaming" technology has been wire-grid delivery services will be optional, much mostly explored in military weaponsand aerospace like cable TV of today. In the 21st century, applications and is now being developed for Direct TV is the rage, which is an exact parallel commercial and consumer electronics Low-Power of Tesla s Direct Electricity. applications. Wireless energy transfer system using 6. RECENT EXPERIMENTS laser for consumer space has to satisfy Laser safety 1) Intel Company makes an experiment and proved requirements standardized under IEC that wireless transmission it is possible. To develop an understanding of the trade-offs of 2)The Indian Express, Bangalore, Thursday, Laser ("a special type of light wave"-based system) September 27, 2007 BUDDING SCIENTISTS 1.Propagation of a laser beam (on how Laser beam Electricity in no more a miracle thanks to the propagation is much less affected by diffraction efforts of scientists like Nikola Tesla, Thomas Alva limits) Edison, Benjamin Franklin and Samuel Morse. In 2.Coherence and the range limitation problem (on simple worlds, electricity is defined as the flow of how spatial and spectral coherence characteristics electrical power or charge through a wire. Omar of Lasers allows better distance-to-power Ahmed Khan and Daniel Fu, 12th standard students capabilities ) from Bishop Cotton Boys' School have generated a ISSN: Page 95

5 wireless electric circuit which conducts electricity qualitative and quantitative. Dr.N.Tesla is the without wires. pioneer of this invention. Wireless transmission of The endeavor began in April 2006 which is inspired electricity have tremendous merits like high by the works of Nikola Tesla whose experiments transmission integrity and Low Loss (90 97% failed due to lack of funds. Say the young talents, efficient) and can be transmitted to anywhere in the "Though many experiments have globe and eliminate the need for an inefficient, costly, and capital intensive grid of cables, towers, and substations. The system would reduce the cost of electrical energy used by the consumer and get rid of the landscape of wires, cables, and transmission towers. It has negligible demerits like reactive power which was found insignificant and biologically compatible. It has a tremendous economic impact to human society. Many countries FIG.Intel Wireless Power Transmission been carried our regarding electricity, there has been a dearth of a full-fledged project. The recent experiment by MIT, where they used a nonradiating magnetic field was also very expensive and non compatible. On the contrary, Omar and Daniel's Wireless Circuit is purely based on principles of Electromagnetic Resonance, Electromagnetic Induction and Turns Ratio. The wireless electric circuit consists of Iron bars with Copper Turnings..."The concept can be used to lighten the weight of a Formula 1 car and reduce expenditure on lightening of an aircraft using no wires. This project they say is dedicated to Dr. Raja Ramona, alumni of Bishop Cotton School. He is a great visionary figure. 3)A test of a wireless broadcast of solar power has been carried out which was able to transmit energy RF energy over a distance of up to 148 kilometers (about 90 miles) - almost 100-times further than a major 1970s power transmission performed by NASA in the Mojave Desert in California. 7. CONCLUSION The electrical energy can be economically transmitted without wires to any terrestrial distance. Many researchers have established in numerous observations, experiments and measurements, will benefit from this service. Monthly electric utility bills from old-fashioned, fossil-fuelled, loss prone electrified wire-grid delivery services will be optional, much like cable TV of today. 8. REFERENCES [1] Nikola Tesla, The Transmission of Electrical Energy without Wires as a Means for Furthering Peace, Electrical World andengineer. Jan. 7, p. 21, [2] Nikola Tesla, My Inventions, Ben Johnston, Ed., Austin, HartBrothers, p. 91,1982. [3] Thomas F. Valone, Tesla s Wireless Energy... For the 21stCentury!!! One Step beyond Direct TV!!! Extra OrdinarTechnology, 1, no. 4, Oct / Nov / Dec2003. [4] James O. McSpadden, Wireless Power Transmission Demonstration, Texas A&M University, June, [5] Thomas W. Benson, Wireless transmission of power now possible, News Letter, pp1118 9, March, 1920 [6]Science reporter magazine [7] Wikipedia the free encyclopedia. [8] Brown., W. C. (September 1984). "The History of PowerTransmission by Radio Waves". Microwave Theory and Techniques, IEEE Transactions on (Volume: 32, Issue: 9 On page(s): ISSN: ). [9] HISTORY OF WIRELESS Tapan K. Sarkar Robert J.Mailloux Arthur A. Oliner Magdalena Salazar-Palma Dipak L. Sengupta. [10] ]POINT-TO-POINT WIRELESS POWER TRANSPORTATION IN REUNION ISLAND 48th International Astronautical Congress, Turin, Italy, 6-10 October IAF-97-R.4.08 J. D. Lan Sun Luk, A. Celeste, P. Romanacce, L. Chane Kuang Sang, J. C. Gatina - University of La Réunion - Faculty of Science and Technology. ISSN: Page 96