In the next decade, you may see a mobile whose battery never gets discharged and charges automatically without wires and contact to any charging mat. Do you think that’s a possibility?
If I say, in the next decade electric cars would no more have the plug in socket for charging. Will you buy that car?
If I say that, from next decade onwards these copper wires and all power line wires will start to move towards their extinction. Will you can you envisage a museum dedicated to the “Journey of Wires”?
Well, I guess many of you out there will not believe these predictions. But the people who trust these words know something or everything about the basis on which I am saying these things. I am making these predictions on the recent success in the field of Wireless Power Transmission.
Wireless power transmission is already in use but on a very small scale. All radio stations transmit their programs using the electromagnetic energy and we even have wireless charger for some android devices. Wireless Power Transfer Technology is an emerging trend in the world today. This technology eliminates the drawbacks of existing wired technology.
Let me acquaint you all with some basic details of this “WIRE-FREE” technology.
What is Wireless Power Transfer?
Wireless power transfer or wireless power is the transmission of electrical energy from a power source to an electrical load without interconnecting wires. Wireless transmission is useful in cases where interconnecting wires are inconvenient, hazardous, or impossible.
Wireless Power is commonly known by many terms, including Inductive Power Transfer (IPT), Inductive Coupling and Resonant Power Transfer. Every term essentially describes the same fundamental process – the transmission of energy from a power source to an electrical load, without connectors, across an air gap. The basis of a wireless power system involves essentially two coils – a transmitter and receiver coil. The transmitter coil is energized by alternating current to generate a magnetic field, which in turn induces a current in the receiver coil.
Contributors in the Invention
Sir Heinrich Hertz: The idea of inductive power was made possible in 1888 when German physicist Heinrich Hertz proved the existence of electromagnetic waves by creating a spark gap transmitter and receiver. A spark generated by the transmitter also created a small spark in the receiver, which could be seen with a microscope.
Nikola Tesla: Nikola Tesla, who is seen by most Americans as the “Father of Wireless”- and is also credited for his remarkable AC generation – became the first person to conceive the idea of wireless power transmission. He successfully demonstrated the transmission of electricity without wires as early as 1891. In 1893, Tesla won won the World Columbian Exposition in Chicago, where he demonstrated the success of illuminating the vacuum tubes bulbs without using wires. Tesla also constructed the Wardenclyffe Tower for wireless power transmission of electrical power rather than telegraphy. Tesla conducted his experiments in Colorado Spring in 1899. He was also able power the 200 (50W) incandescent lamps at 25 miles from the power hour source without using the wires.
William C. Brown: William C. Brown is credited for modern research and father of microwave power transmission. In early 1960s Brown invented rectenna which directly convert microwave to DC current and in 1964 he successfully demonstrated a microwave-powered model helicopter that received all the power needed for the flight from a microwave beam at 2.45 GHz.
Marin Soljacic: A physics research group led by Prof. Marin Soljacic at the Massachusetts Institute of Technology (MIT) demonstrated wireless powering of 60W light bulb with 40% efficiency at 2m (7ft) distance using two 60 cm diameter coils in 2007. They used resonant induction to transmit power wirelessly. The group is also working to improve the technology. This came as a chance when Prof. Soljacic’s phone beeped in the kitchen letting him know that he forgot to charge. Soon after the success of the experiment the term for the technology was given as WiTricity and to carry out this technology forward from the MIT laboratories, WiTricity Corp. was launched.
It is only in the last decade that the technology has been harnessed to the point where it offers real, tangible benefits to real world applications. In particular, the development of resonant wireless power technology for the Consumer Electronics market, has seen wireless charging deliver new levels of convenience for the charging of millions of everyday devices.
How does it work
The basics of wireless power involves the transmission of energy from a transmitter to a receiver via an oscillating magnetic field. To achieve this, Direct Current (DC) supplied by a power source, is converted into high frequency Alternating Current (AC) by specially designed electronics built into the transmitter.
The alternating current energizes a copper wire coil in the transmitter, which generates a magnetic field. Once a second (receiver) coil is placed within proximity of the magnetic field, the field can induce an alternating current in the receiving coil.
Electronics in the receiving device then converts the alternating current back into direct current, which becomes usable power.
Below is the list of all the different techniques for wireless power transfer:
Near-Field Techniques
Far-Field Techniques
Benefits of Wireless Electricity:
- Reduce costs associated with maintaining direct connectors
- Greater convenience for the charging of everyday electronic devices
- Safe power transfer to applications that need to remain sterile or hermetically sealed
- Electronics can be fully enclosed, reducing the risk of corrosion due to elements such as oxygen and water.
- Robust and consistent power delivery to rotating, highly mobile industrial equipment .
- Delivers reliable power transfer to mission critical systems in wet, dirty and moving environments.
Disadvantages:
- Wireless power Transmission can be possible only in few meters.
- Efficiency is only about 40%
- Need for standardization and adaptation. So, a little overheating occurs because of different voltages
- Refitting old equipment or purchasing new equipment could become a very expensive endeavor
- Possibility of Energy Theft.
- High health risks because of the electromagnetic fields being used to transfer the power.
Conclusion
In addition to the above disadvantages, there are also some challenges for the development of this technology. Solutions for challenges like sustaining the constant power level, damage that could be caused to ozone layer by outer space transmission and much more are being researched on.
Wireless Power Transfer has the potential to change the face of this planet with its implementation with the revolution starting from electronics to the satellites. It will reduce the dependence on the fossil fuels and other petroleum products that directly leads to the global warming.
Currently the technology is in progress and researchers are trying their best to overcome the challenges and disadvantages. WPT is the most sustainable alternative to fossil which could lessen the Earth’s burden by replacing the other harmful techniques.
