batteries could explode. not sure if this would ever pass fcc. perhaps if there was a cabling leading to a battery pack stashed in a backpack or even the bike is better. The turbine could essentially be fitted into the bike itself as well.

NiMH batteries will not catch fire or explode. Li-ion batteries just need appropriate charging controllers to be safe. LiFePO4 cells have less energy density than Li-ion but are quite safe. Battery technology need not be a problem. LED "tail lights" could be added to improve visibility and be a slight load/drain on the battery to reduce the chance of overcharging (the problem with Li-ion batteries). I would want to test this for noise. The ducts and fan and generator bearings cou

As a keen cyclist who commutes 10 miles to work regularly, I'd be interested in one of these when they hit the market...I often use a small bar-mounted wind turbine which i got got christmas but it's inconvenient to charge devices etc due to it's location! One of these which is fully waterproofed (rains a lot here so if water is sucked into the intake?) and with either LED strips or built-in lights front and back would be something I would certainly consider buying (plus it does look rather coo

Ummm...why not just use a generator driven by the rotation of the wheels? Although both have the downside of causing drag on the rider's speed, a generator doesn't suffer from being forced to maintain a perfect forward orientation. Generally, any movement of the head causes this system to have a reduction in output.

Several linear generators mounted within the helmet (in XYZ axis) may accomplish the same task without exposure to the elements by harvesting energy from small movements.

Interesting but, I think the wheel generators would be a better idea, or solar panniers bags.<br /> A Motorcycle could output enough energy to recharge a plug in battery system. Single impact even minor, no more helmet.

Weight?

The propeller will hardly charge the batteries using the wind its too small. Anyway, if you do build a better charger like a wheel charger etc, I don't see how do you help saving the planet like this. You will have to convert the calories you eat to electricity and then you will have to eat more green salads from our dieing planet...

Aside from how inefficient this would be, riding your bike while listening to your MP3 player is DANGEROUS and sometimes illegal. Remove the iPod from your ad.

Poor idea. It's inefficent as a battery charger, lot of secondary problems (weight, complexity, weakness as an helmet, ecc.). Overall, the EROEI is awfull: the energy required for all materaials, components and manufactruring will never be "saved" by the system. Please, do not waste resources producing this object.

eyal avramovich... did you think we will run very fast at bicycle only to recharge the batteries? we can use it to go work or to other places too. i like the idea, but will take some time to recharge this batteries ;)

As a Chicago bike commuter, I hope to see this come to market. I bike about 14 miles per day, weather permitting (which included six days so far in February), and I hate how many batteries I've used to power my little Sony radio (sitting in a box, waiting for me to find the recycler). FYI, it may be pushing the safety question a bit, but I think for all the precautions I take – lights, helmet, clear signals, hyper vigilance – keeping an ear bud in my right (non-traffic) ear poses a minimum