Charger lets you bike for power, not just health
The BioLogic FreeCharge comes in a tiny silicone-encased box that hooks to your generator hub to transfer your body's power into your iPhone.
(Credit: Dahon)Every year at the Multnomah County Bike Fair in Portland, Ore., someone brings a bike hooked up to a blender and lets people pedal their way to their smoothie of choice. Sometimes the simplest, most obvious ideas are also the most brilliant.
So it comes as no surprise that far lighter, more portable charging devices are being designed to fit on bicycle generator hubs. Folding-bike maker Dahon has just unveiled its Biologic FreeCharge at the Eurobike Fair in Friedrichshafen, Germany, and it has the cycling world all atwitter.
The FreeCharge connects to any dyno hub on the market and charges a small gadget (iPod, cell phone, GPS unit, etc.) by transferring some of the energy your body generates pumping away on your bike to a high-capacity battery, which in turn directs a steady current to said small gadget. A simple silicone casing both secures the unit to the bike and seals the charger (although being zapped by the charger might give one that extra push to continue powering the device).
It remains unclear whether the FreeCharge has the capacity to power these devices as quickly as a 120-volt outlet does--a rate that likely also depends on how fast one pedals. Regardless, an iPhone takes around three hours to fully charge, so unless you're touring the countryside (for which this gadget would be perfect), it's more likely that this has more practical use for smaller top-off charges.
The BioLogic FreeCharge should be available for around $99 in March.
Elizabeth Armstrong Moore is a freelance journalist based in Portland, Ore. She has contributed to Wired magazine, The Christian Science Monitor, and public radio. Her semi-obscure hobbies include unicycling, slacklining, hula-hooping, scuba diving, billiards, Sudoku, Magic the Gathering, and classical piano. She is a member of the CNET Blog Network and is not an employee of CNET. 
Contrary to what the article states, it's not unclear at all whether this thing can power devices like an outlet can. The basic facts say it's no comparison. A seasoned athlete is lucky to sustain a couple hundred watts of output for any legitimate amount of time, so your typical rider probably struggles to do 100. At any cruising speed that would generate that, 90%-95% is going towards wind resistance, and you still have to overcome all the friction of the bike itself.
I'd be very surprised if you could take more than 5 watts of mechanical power away without it becoming a serious drag on your biking, so you might have a fraction of that left (2 watts?) once the conversions and efficiency losses are factored in. If an iphone pulls 6-10 volts at 1amp from the wall, that's 6-10 watts. That would probably take 15-40 watts of mechanical drag to generate, which would be like riding with a flat.
I'm not disputing that you can generate a very tiny current; I'm disputing you'll get anywhere near the power a wall outlet provides.
If you want "real world experience", look up some of these devices and you'll find that, even at a couple volts and a fraction of an amp, you do in fact feel the drag from them. If you want "sheer stupidity", how about statements like "your riding the friggin bike anyway". There's no free lunch or free energy--you sound like one of those NPR callers who says we should just put mini windmill generators on our cars. You're driving through the wind anyway right?
Here's a few numbers estimating human body power production during different activities:
"Broken into usable terms, waiting to be harvested are 81 watts from a sleeping person, 128 from a soldier standing at ease, 163 from a walking person, 407 from a briskly walking person, 1,048 from a long-distance runner, and 1,630 from a sprinter, according to the center."
http://www.space.com/businesstechnology/technology/body_power_011128-1.html
The article you reference is a future-tech hypothetical that just multiplies a theoretical yield by your body's total metabolic output. That makes little sense because the vast majority of that energy is simply heat, and the only way to capture that would be to surround yourself with a Carnot engine.
The amounts of actual mechanical energy a person can generate are well studied, and much much lower. Again, if you read about any of the bike generators that already exist, you'll find that what seems like "too little to notice" actually equates to quite noticeable drag to get enough of a trickle for low-power devices like LEDs.
As a kid I was always fascinated by "free" power in the form of wind up radios, those nifty flash lights you shake back and forth, and portable solar panels. Then I learned some physics, and realized that when you're dealing with multiple orders of magnitude, you can't just assume that a continuous tiny output will add up. The whole point of the industrial revolution was the ability to do 100, 100,000, or 100,000,000 times the work any person could ever do manually, even if he never slept.
That's why your bike charger won't ever approach the output of an outlet, or cover the portion of your electric bill your workout costs, and why those shaky flashlights take 90 seconds of vigorous shaking for 5 minutes of miserly runtime.
Humans are inefficient
When you're talking about orders of magnitude, "every little bit" just doesn't count.
3 hours of working out will buy you 3 hours of a single 100 watt light bulb, minus the efficiency costs of converting mechanical work to electrical energy, transporting it, storing it, converting it to the correct phase, etc.
If you want to translate it into money saved, we need kilowatt hours. 100 watt workouts will give you a kilowatt in 10 hours; 200 watts would give you that in 5. Electricity ranges in costs from about 6 cents/kwh in the free states to about 14 in the most regulated urban ones.
So every 5-10 hours of workouts might earn you a very optimistic 3-7 cents of electricity after efficiency losses. Put another way, you could keep a radio running during your workout, but not even keep the room lit or cover the energy it took to make the coffee that got your awake enough for your daily workout session.
My generator powers my front light, which has a 3 watt bulb, and it's at full brightness at about 8mph, so I recon that there is plenty of power for a gps or an iPod.
That said, I can't see any point in having this kind of charger if you have regular access to another power source.
Dynamo bike lights are mandatory in europe - intended to reduce collisions at night. If we can make the biking experience more pleasant by enabling more comfort activities like running the latest electronic gadgets, then I'm all for it.
I'm not sure how cost effective it would be on a bike, but perhaps just a remote engage cable for the normal dynamo would work. Perhaps you could even tie it into the brake controls.
Most cyclists have encountered pain in the buttocks, back, knees and legs, but increasingly, foot pain is on the rise. There is growing evidence that the downward pressure exerted in cycling can encourage such foot problems as plantar fasciitis, a painful irritation and swelling of the thick tissue on the bottom of the foot. Today?s cycling shoes are largely ineffective in addressing foot pain, and available insoles aren?t much better.
For various reasons bicycling shoes are structurally minimal and have been designed to be tight fitting, offering little room for support additions. Most cycling shoes today have removable insoles that are designed for what the manufacturer would call a perfect fit, but provide little, if any true or functional support. They are almost always the lowest cost materials that could be used, and lose what little support they do have in a very short time.
Maximum shock protection in a minimal profile
Orthotics specialist Michael Kendall has studied foot dynamics for more than 20 years, with an emphasis on creating an effective shoe insert that would be effective in the reduction of foot pain while fitting in more types of shoes than almost any other orthotic. His work has included focusing on the relationship between cycling biomechanics and foot pain. The result of 10 years of study is the GelThotic, a revolutionary orthotic designed to authentically support the foot but still fit in bicycling shoes. The GelThotic, constructed of a medical-grade silicone, combines an unparalleled combination of shock absorption, memory and resilience.
In his research, Kendall has discovered that hard surfaces are always detrimental to the human foot, so inserts made from carbon graphite can damage the soft tissue of the foot. The reason is that it cannot be completely or directly matched to the foot, such as in a custom orthotic, so the foot is susceptible to irritation and pressure sensitivity. A foam insole does not deliver enough protection since it will compress, affecting the perfect fit of the adaptive, non-compressible gel. Kendall?s GelThotic is the preferred intermediary since it creates a perfect fit directly against the foot using soft medical grade Silicone. In this way, the power transfer on the downstroke is completely optimized and enhanced.
The cobra-shaped GelThotic insert provides one of the highest levels of shock reduction ever tested, and is designed to fit into the limited space of a bicycling shoe. Its design is the essence of support, yet unlike full insoles that take up the "floor" of the orthotic and the shoe, the GelThotic fits under the existing insole. This allows the studied fit of the shoe and the support of the orthotic to work in tandem.
Cycling and foot pain
The patented minimal design of the GelThotic alleviates pain in the heel, arch and forefoot while controlling pronation (the tendency for the sole of the foot to face more laterally than when standing in the anatomical position). But the GelThotic has been designed to encourage the foot to be held anatomically and biomechanically in a position that minimizes foot pain and pronation.
Most orthotics have little effect on foot correction because the support characteristics are oriented for the heel and ankle which has diminished effect in the toe clip or on the pedal. A fundamental part of its patented design is that the support extends all the way to the forefoot (first ray extension) making it much more effective in the bicycle?s clip.
Further, hard surfaces seem to cause irritation to an already inflamed injury. Typical orthotics or supports may actually further the injury, not only from the poor fit of the shoe holding the orthotic but also from the hard surfaces which aggravate the injury.
The GelThotic is made from pure medical grade silicone which is soft against the skin but has been engineered to have functional medical structure. Placing the GelThotic under the footbed in cycling shoes or on top of the footbeds, prevents toe crowding while creating the shock absorption so important to preventing foot pain. The GelThotic fits both men's and women's shoes. The SRP is $69.95 and is available at many locations or can be purchased directly from FootCare Systems by calling 858.350.1129 or online at footcaresystems.com.
- by tmiddlem November 10, 2009 1:41 PM PST
- What about essentially turning your fork and front wheel into an alternator with copper wire and magnets? Granted someone would likely rip the copper wire off instantly...Also, the bike's front end would be ridiculously heavy, but no friction should be involved.
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