The article explains how in the “wire-free minimalist culture” that we live in, everyday use devices tend to become wireless. Some (such as PC’s, TV’s, or radio and music players) are starting to be implemented to work with no need of cables. Others (like cell phones, laptops, or mp3 players) already function almost completely wirelessly. However, all of these devices still need to be physically connected, either permanently or at least each certain time, to the power supply. For many people, this is a big inconvenient that should be eliminated. The fact of simply having to manually connect our devices to recharge batteries is seen as something uncomfortable and old-fashioned.
Engineers have in mind different solutions to this problem. There are essentially three different approaches, each of them with its advantages and its disadvantages. The first and probably the most obvious and simplest solution would come with the transmission of electricity through radio waves. The article explains how this system would be implemented by simply adjusting the Wi-Fi technology for the transmission of electrical signals “using the same kinds of transmitters and receivers used in Wi-Fi communication”, thus with no need to create new maybe complicated and costly infrastructures. However, it is not clear whether this system could power any kind of device (researchers see this option more as a wireless power supply just possible in short distances and only feeding small electronic devices or those which don’t require much power to function).
A second approach consists of emitting infrared lasers and capturing them with photovoltaic cells (similar to solar panels) that convert the beam into electrical energy. Again, this technology has its pros and cons. On one hand, it allows for transmitting relatively big amounts of power (at least more than in the case of the system previously mentioned). On the other hand, it requires a line free of any obstacles from the emitter to the receiver, which doesn’t sound very functional.
The last option that the article talks about has to do with the use of magnetic induction, phenomenon by which common electrical motors or transformers that we all have in our houses work (essentially a varying magnetic field generated through a coil induces electricity into another proximate coil). This could be used as a wireless power system. Recent research has actually shown this as a real possibility. Lately, the key has been the development of a resonant system of induction, making the frequencies at the emitter equal to those at the receiver to make sure the energy is transmitted in phase with the one that has already been sent before, so that the new transferred energy completely ads to the one already sent. This is just a way of gaining in efficiency; without using this technique, each time there was an emission of energy, most likely, part of it would be lost.
From my point of view, this article presents a relevant issue, considering that wireless transmission, experts say these days, is the way in which all power will be transmitted in the near future. Indeed, I believe that implementing any of these systems successfully would be useful for us or, at least, make our lives easier. It would save us a lot of time and, without doubt, avoid us many upsets. How many times were we unable to make an important phone call because our cell phone simply ran out of battery? With this invention we wouldn’t have to worry about manually charging our electronic devices because it would simply be done automatically, not to mention the improvement in aesthetics it would involve (our homes look better with no wires). The important thing will be, as always, to develop a system not harmful for people. We all know that for instance lasers or electromagnetic fields can have negative effects in our bodies. It is the responsibility of the engineers involved in this research to preserve and protect the security of the future users of the device.
Here's a link to the article in question
http://www.newscientist.com/article/mg20527461.300-unplugged-goodbye-cables-hello-energy-beams.html?full=true
