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Using Gym Rats' Body Power to Generate Electricity
Carl Bialik from WSJ writes "A Hong Kong health club is hoping that a car battery, some StairMasters and dozens of gym rats can help ease the world's energy problems. It is just one of a wave of projects that are trying to tap the power of the human body, the Wall Street Journal reports. The article explains the impetus behind the project: 'The human power project at California Fitness was set in motion by Doug Woodring, a 41-year-old extreme-sports fanatic and renewable-energy entrepreneur, who pitched the experiment to the gym's management last May. "I've trained my whole life, and many megawatts have been wasted," says Mr. Woodring, who has worked out at the Hong Kong gym for years. "I wanted to do something with all that sweat."'"
The muscle has a efficiency far below 30%.
Though if they could somehow manipulate the dna to create brainless bodies, those could be used as warming bags. You would put a few of them here and there in your home to heat it up. They would be connected to a food and waste facility. And with an intact immune-system and other body functions they would be maintainance free.
I'd agree, I cycle a bike everyday and wouldn't put a dynamo on it. See, the difference with a dynamo on your bike is that you're not tapping energy that would otherwise be wasted, you're sapping the energy that should be going towards moving you between A & B. Sticking a dynamo on an excercise bike may not be such a bad idea, but slowing yourself down to squeeze a few joules into your phone is just silly.
FGD 135
It was good excercise, but also incredibly dangerous and we created pollution in the process. Chainsaws, tractor, log splitter, etc. I can't imagine cutting wood without these machines. At least not for the big farm house we lived in. I guess that's why the little house on the prarie was so damn small.
Err... you'd want to watch the gearing ratio. Using a friction pin against the wheel, say the friction pin was large at 5cm in diameter, that's still an insanely high gearing ratio. The motor would put out hundreds of volts and probably fry your phone. Perhaps using an intermediate battery as a voltage regulator would be a good idea.
I hate printers.
Wasn't this an easter egg in Fallout? There was a bonus area that randomly appeared. It was a building where several people inside were running on treadmills, generating power. . .
"Remind me again why you treadmill people don't just go outside?"
Well, lets' see . . .
below zero(F) temps with high winds
Sunset prior to the end of the work day
Precipitation
Treacherous footing
narrow roads with high snow banks
I love to run outside, but it's not worth frostbite, a twisted knee or ankle, or being hit by a car.
I actually ran the numbers once. I was sitting there on an exercise bike in the basement in winter, and I was really bored. I thought, "I could be generating electricity now". I couldn't find a food source that would provide you the energy to convert into . . . energy . . . economically even if you were paying 25 cents/kWh for your electrical power. And I made some pretty generous estimates of human efficiency, too. At least that effort made my ride to nowhere go by a little faster that morning.
I am not a crackpot.
To put this in perspective, this is like saying each person is outputting sufficient energy to boil 166 jug kettles simultaneously.
Please, think about your numbers before you post them. I think you mean a kilowatt. These people would be hotter than the Human Torch, people would be running, screaming, their lycra pants melting from their roasting flesh.
While I agree that the wasted energy which is ordinarily all just converted into heat in the gym atmosphere would do something useful before it ends up in it's ground state, if you could generate a megawatt from six people on bicycles, every major city in China would be a roiling cloud of vapour. Either that, or they'd have built a huge deathray and vapourised the West by now.
I use a Precor at the local Y - it seems as if their line of exercise devices (at least the non-impact ones) have been cord-free for quite some time. It's not a treadmill (which will always take power unless you really want odd resistance) but it's self contained and might be easier on your joints over time...
Karnal
For example, a handy that is powered by movement, and thus stays charged forever aslong as you're walking/moving would be a very practical thing to have for many people.
The reference to "handy" is probably meaningless to most Slashdotters, but it's what Germans call a mobile telephone. I have no idea if the term is in use in Austria or Switzerland, but I've seen it used in Germany.
Those calories are kilocalories. So your average power is actually 2,800W. But we know that can't be right. First those calorie calculators are very innacurate, they just get you in the ball park. Second, that's the amount of energy you're burning to produce the motion, but your body is very inefficient. So you may be burning 2,800J/s of energy, but the usable output of work could easily be 1% of that. And then as you said, you have to worry about the efficiency of the generator.
Actaully the top peak wattage of sprinters is somewhere in the 1200-1600 range. But that's peak. Lance on a 1 hr TT, sustains about 400-450 watts.
And from my experience, 200W is pretty high for the average person that I know. I'm thinking 150W sustatined is probably more realistic for average weekend riders.
I think 1 hr is a better measure than 100 miles, since I don't think people will sit on an exercise bike for 5 hours.
Also I think the bike is probably going to be the most efficient transfer mechanism to generate power. Somehow I don't think you'll get the same efficiency on an elliptical or a treadmill...
I usually walk to the gym from work, but I do work out one day on the weekend. I drive to the gym. I'd estimate it's a 30 minute walk, 10 minute drive.
I don't care about the calories I could have burned, they're insignificant compared to the calories I burn from deadlifting and squatting. All it's going to do is keep me away from my post workout protein shake and boost my cortisol levels. Deadlifting is far better for burning energy than jogging. If I wanted to run, I'd do some 40 meter sprints in my neighborhood, I don't need the gym for that unless it's raining. While I am into serious weight training, most people would be better off deadlifting, squatting, or sprinting rather than jogging.
I'm afraid you've been mislead. Take a look at www.caloriesperhour.com and do some calculations based on your weight. Jogging will come out on top.
Yes, you can make the argument that powerlifting builds muscle mass and thus burns more calories at rest. Jogging raises your metabolism and essentially does the same thing.
The number of calories burned is somewhat irrelevant though. For optimum health, you need both aerobic and anaerobic exercise. Balance is good.