Since I started Electric Pedals back in 2007, I've always wondered if it's possible to pedal and use a computer at the same time; and more importantly maintain a balance of power between supply and demand, that is supply from me pedalling vs. the energy required to run a laptop.
This idea is my no means new. I first saw the concept in 2008 or an Innovate or Die competition at ULC Davis. Students built an amazing product that I initially thought would do really well; sadly it never go off the ground. Since then there have been a few attempt to recreate this but again the idea has not really taken off... maybe we are just too damn lazy or dependent of fossil fuels to give it a good try.
I'd never bother testing our own version previously as our bicycle generators are quite inefficient. A lot of energy is lost due to friction connecting the tyre to the motor, not to mention the losses in a bicycles transmission. So we finally find a suitable motor (above), and boy is it efficient. I can honestly say that the above generator IS the most efficient way to transfer energy from your body into electricity using a pedalling motion.
So what else is need to get the energy from your body into your laptop? Well, a very big capacitor for one (that the blue bit). This is used to smooth the energy between the pedal generator an the laptop charger and stores a little bit. There is a regulator in the sandwich box to stop me overcharging the capacitor (and it exploding) and a standard 12v car charger for my MacBook Pro.
The whole kit is pretty minimal and every component is off the shelf. it's just been assembled in a unique way to make this happen. I had to test it in the kitchen on the worktop as my knees would not clear the underside of a regular table. I'm not sure there is much can be done about this without making the pedal arms shorter.
So how was it? Well it really works. It's not as easy as i thought, but I do own probably one of the most energy greedy computers (MacBook Pro 17"). It consumes about 80Watts which is quite high for a laptop. I found that I could pedal and type quite easily and If I'd have had a bit more clearance under the work top, I could have got the computer a bit closer to stop me slouching. I tried for an hour and managed to maintain the battery percentage, I certainly didn't get into to go up!
So is it feasible? Yes it really is. With a few suitable changes and some practice the Pedal Desk could be a reality. Of course, the biggest challenge is going to prize people away from the energy artery that is fossil fuels.