Let's consider for a moment that unglamorous object which has (quite literally) over the past two decades powered the mobile revolution. The humble battery. The problem is with batteries is that they're not very nice.
I cannot imagine how many get thrown away each year, or what their half-life is in terms of decomposition. With over 4 billion mobiles in the world, surely this is an environmental crisis waiting to happen? We carry mobiles with us as we move around, just as we do with the watches that we wear. Watches can wind and charge themselves up with kinetic energy - why not mobiles? Personal power generation is nothing new, but my view is that it is something not publicised enough. We all know about the wind up radio or torch but what about the mobile equivalent?
A few years ago, Orange (the UK mobile operator) tested a personal power system at Glastonbury music festival. It was an ingenious invention using the kinetic energy that we create by dancing. Orange supplied a small and simple strap-on kinetic transformer in which you place your phone, you strapped it onto your arm and the movement of dancing recharged your phone.
A year later, they promoted another version which used a heat transfer sole in your shoe which was connected to your mobile battery - again charging your phone via the heat through your feet that dancing generates!
Neither of these devices became popular, either because Orange didn't release them into the market - or because people just don't dance enough…
At the time of the Glastonbury trials, I thought that the systems were a great way of charging your phone and they produced great big PR stories, but wouldn't it be incredible if one day they actually could replace your battery?
Enter Intivation at MWC this year. A brand new company who I am sure most would have missed. They only had a small stand in a corner but their tagline is big: 'Mobilizing the Sun.' They propose to do en-masse mobile power with solar panel technology that can be integrated into a whole host of mobile handsets. The tech looks beautiful, definitely something desirable to consumers. It's still not quite replacing the mobile phone battery, but getting much closer and it got me thinking about mobile power in general.
After a little research, I found a lot has been done on wireless power and there are many products about to hit the market including cordless TV's which take their power wirelessly over fairly large distances. Here's an Eric Giler demo of wireless electricity with a TV at TED.
Then I realised this is nothing new (see this NASA film of 1975 where they used a wireless transmitter to send 34,000 watts over 1.5 kilometers at an efficiency of 82% - this video is incredible!
Again this got me thinking, but this time about wireless power harvesting…
So, if they can send power to devices wirelessly, maybe they can make devices that can harvest power wirelessly, from the air that surrounds them. I was thinking about the ambient radio waves that surround us all the time (like TV, radio, microwaves etc). This then led me to find these experiments.
If anyone out there knows of more examples of similar research, please do let me know.
The thing is… if mobiles could one day charge themselves, then go further to perhaps store excess power, we could perhaps use them as personal power cells! Imagine arriving at the office and the lights are out in your meeting room. You could take out your phone, plug into a wall mount and hey presto! You could light up your office with your personal power cell.
Far-fetched thinking perhaps, but wouldn't it be great if we could turn around the potential environmental crises of the mobile phone battery?