When Nikola Tesla showed that energy could be transferred wirelessly in the late 1800s, he gave birth to an idea that would only be realized in recent years.
Wireless energy transfer first began to attract mainstream media attention early in 2001 when online science news site Space.com touched on the subject of wireless power transfer in space in an article about new power sources to meet increasing demand. Now, only a decade later, wireless energy transfer is on the tip of everyone’s tongue.
How Wireless Energy Transfer Works
Wireless energy transfer does exactly what it says on the tin – it enables the powering of devices and appliances without the need for wires and cables. It works by making use of the principle of resonant coupling – devices and appliances use copper coils which, when tuned to the correct frequency, resonate with one another.
One coil is plugged into the wall while another is attached to an electronic device. The wall coil creates an electromagnetic field which resonates with the latter coil, which generates some energy in the process which will power the particular electronic device.
Any obstacles sitting between the device and the wall coil are inconsequential to the power transfer, and human beings are unaffected because the human body does not respond to magnetic fields.
Limitations of Wireless Energy
A number of companies and academic institutions (including Intel and MIT) are involved in a race to be the first to release marketable wireless energy packages, however, there are a number of limitations to the full implementation of wireless energy transfer:
1. Size: the copper rings which create resonance and energy are simply too big for them to be part of any wireless energy package.
2. Range: the range of wireless energy transfer is just a few meters, which is a major hurdle.
3. Efficiency: wireless energy transfer ensures between 45% and 80% of the energy put in is transferred, which is much less efficient than regular wired connections.
4. Cost: the cost of developing and implementing wireless energy networks means that it would be too expensive for the end-user to afford at this point.
These limitations, however, do not mean that marketable wireless energy cannot be achieved – already companies like Powermat have released a wireless charging ‘mat’ for everyday mobile devices, with the promise of much more to come.
The Future of Wireless Technology
When Wi-Fi and wireless internet as we know it was first developed in the early 1990s, it was revolutionary. Now, no more than twenty years later it is commonplace and mundane. Almost every bar one walks into boasts either free or paid-for wireless services enabling customers to check emails and surf the net. It would make perfect sense to say that wireless energy transfer is going to go the same way.
In line with this vision it would be safe to assume that one day a person would be able to walk into a bar of coffee shop and would not only be able to have instant access to the internet but would also enjoy any devices they have on them being powered or charging automatically.
It does not seem that this would be very far from the truth, especially with companies like Witricity promising marketable wireless power by the middle of 2011. Apart from the commercial gain and its convenience, however, wireless power does offer to fight a more noble cause as well.
Renewable Energy Sources
The grandfather of wireless energy transfer, Nikola Tesla, in the 1890s pointed out that one day all electronic devices would be able to harvest the electromagnetic energy which was naturally present in space. To consider this presents one with a mind-blowing array of possibilities. If one were able to create electronic devices which would harness the energy in space, then one would have essentially created a renewable power source, and the implications of that would be immense.