Notions of Expenditure

April 11, 2005 8:45 AM

Huff & Puff Energy"Think about it. We go to the gym every day, get on a machine and expend great amounts of energy. Multiply that by everyone in your gym, in all the gyms in all the world and what have you got? a lot of power! This project is a request "for speculative proposals to re-design exercise equipment to generate and store energy; and/or to retrofit gyms to function as local power sources linked to the grid." It envisions a redesign of gyms into power hubs and a linking together of the power hubs into a massive power network. All this and get fit too." [via Treehugger]
posted by azul (54 comments total)

Did we just have a movie version of this?
posted by gimonca at 8:53 AM on April 11, 2005

I've been saying this for absolutely years. The first time I went to a gym and saw all those bodies pounding the bikes and treadmills, I thought "why not hook these things up to simple dynamos and use the power?" It always seemed so obvious.
posted by Decani at 8:54 AM on April 11, 2005

hamsters.
posted by quonsar at 8:55 AM on April 11, 2005

I would never have thought of this, but it seems like a fabulous idea. Now, would this lead to people getting paid to exercise (which seems like just the incentive needed for chubba North Americans), or just do away with gym fees?
posted by orange swan at 8:58 AM on April 11, 2005

Order of magnitude: about 100W per human. Which means an ordinary light bulb or so.
posted by fatllama at 9:09 AM on April 11, 2005

I'd be surprised if exercise machines could ever do more than power the powerful ventilation equipment. Modern gyms move a serious amount of air in an attempt to prevent the place from smelling like a giant armpit.
posted by 4easypayments at 9:14 AM on April 11, 2005

Wow, what a neat idea.
posted by agregoli at 9:16 AM on April 11, 2005

I've seen this suggested quite a few times. However, once you start looking at the power output the average human can maintain for any period of time, even in intense exerise, you'll realise why this hasn't been done in practice. This site suggests that a healthy human can maintain an output of around 300W for an hour, good perhaps for keeping the gym nice and bright, with a fair number of work stations then the gym might be able to contribute to keeping its air conditioning going, but the potential to supply power to outside users is not significant. A KWh is a lot more energy than most people seem to think.
posted by biffa at 9:17 AM on April 11, 2005

I remember the eliptical I used to use at my local gym would show your energy output in watts. I seem to remember about 250 watts at some point. (that'd be about 3 kcal burned per minute. what's listed ad "calories" on food packages are actualy kilo-calories of standard mesure energy units, or 4.184 joules in SI units)

Anyway, every thousand food calories you burned, you generate about 1.2 killowatt hours, or 15 cents worth. Assuming no loss through body heat. and assuming the average person burns about 500 food callories in an hour an eliptical would generate about $1.35 worth of electricity a day

So I guess one eliptical, if it were fully utilized all day, would power one small apartment. But that would probably require 18 people. If we figure each person works out twice a week, that means we'd need 63 distinct people doing 500 calorie workouts twice a week to power one home.

So, not really practical IMO.
posted by delmoi at 9:18 AM on April 11, 2005

Oh yeah, gyms seem to have a lot of lighting, so I'm I doubt that they'd be able to put out more then they take in. They usualy also need air conditionting (unless they're in alaska or something) because people working out create a lot of heat.
posted by delmoi at 9:22 AM on April 11, 2005

I think those of you dismissing the idea as impractical aren't really thinking in terms of scale. Every gym, in every city in the US? That'll add up. At the very least, they can help power themselves, which will save money and fuel in the long run.

Incidentally, quite a few pieces of gym equipment with electronic components already use this concept to partially power themselves.
posted by kyrademon at 9:33 AM on April 11, 2005

gimonca: this idea of excercise equipment for energy was used directly in Soylent Green, too.
posted by boo_radley at 9:34 AM on April 11, 2005

Hm. So that's another non-original idea I had :(
posted by AwkwardPause at 9:36 AM on April 11, 2005

It would be cool even if if gyms only used treadmill power to partially meet their own electrical needs.
posted by fshgrl at 9:38 AM on April 11, 2005

so let me get this straight...

i don't want do something (e.g. sweep) so i get a machine (vacuum) to do a lot of the work for me. but that machine sucks electricity, which is expensive. so i go across town to exercise, meanwhile producing the electricity that allows me to avoid exercising at home.

that's the best idea since bottled water.
posted by scottreynen at 9:41 AM on April 11, 2005

Yes! Yes! Hook the joggers up to treadmills and force them to generate electricity! (Edward Abbey suggested the same thing in one of his novels). Anything to get 'em off the fucking sidewalks.
posted by jonmc at 9:42 AM on April 11, 2005

I don't think anyone would imagine this sort of scheme could do much beyond make a small (but significant) contribution to the power bill of the gym. But modern gyms tend to have anywhere between 15 and 50 (or more) aerobic machines and - certainly in the city gyms - most of these are in constant use. Given that, enough power could certainly be generated to significantly affect the electricity bill. Plus, there's the ecological factor. Minor, maybe, but we're talking about something for virtually nothing here. It seems worth pursuing.
posted by Decani at 9:42 AM on April 11, 2005

Build an ashtray and a place for my coffee into one of those stationary bikes and I'll power a city, I tell you.
posted by KevinSkomsvold at 9:48 AM on April 11, 2005

Upright Citizens' Brigade had an episode based on this premise as well.
posted by jbrjake at 9:53 AM on April 11, 2005

Let's not forget the immense amount of energy in raw materials and effort that it would take to wire every treadmill in every gym across the world. How long would it take to just recoup that investment?

Now, if you could do something simpler, like make the machines in a gym just help run the ventilation system, that would be easier. The energy savings is the same. If there's no way for any one gym to produce more energy than it consumes, conservation makes more sense as a model than production.
posted by dammitjim at 9:57 AM on April 11, 2005

Why not take it one step further, and put a couple of wheels on these machines? People could get exercise and transport themselves to work at the same time.
posted by weapons-grade pandemonium at 10:02 AM on April 11, 2005

I once stopped at some all-natural/organic/green/eco-friendly place on US 101 up north of San Francisco that had some stationary bikes hooked up to lightbulbs. It required a pretty brisk pace just to keep the thing lit, so I'll echo what the others have said about this idea not being entirely useful. Perhaps these bikes would be best used to move people around and reduce the use of fossil fuels?

On preview: WGP beat me to it.
posted by DakotaPaul at 10:06 AM on April 11, 2005

This occurred to me and then I mothballed it because of the economies of scale, those hand cranked Y2K flashlights just make me feel like blundering around in the dark. However, what if you hooked the bike up to a flywheel, that stored up a certain charge and then shocked the shit out of you, letting you know that you had pedaled enough?

It's not a good idea economically and it might kill some people, but it would be funny, funny like when the toast pops out the toaster, somehow the way it shoots up like a little square spawning salmon made of bread and arching, arching for freedom... I dunno... I just laugh and laugh.
posted by Divine_Wino at 10:15 AM on April 11, 2005

I too had this idea quite a few years ago. I actually thought it would be cool to couple this to a userid based credit system (RFID anyone?), which would keep track of how much energy you produce for a month, then either offer credit for things like special classes, massage, protein shakes, or just offer a reduction of monthly dues.

Another benefit of this would be automatic tracking of all aspects of your workout. You could use thin client touch screen terminals to see your progress, get workout suggestions, etc.
posted by pjsunray at 10:27 AM on April 11, 2005

Someone's been watching Upright Citizen Brigade re-runs...
posted by AlexReynolds at 10:32 AM on April 11, 2005

couldn't someone figure out a way to make it output more energy, to make it worthwhile? (how does one dynamo, or one waterwheel, etc, create so much energy?)
posted by amberglow at 10:39 AM on April 11, 2005

In Africa, the energy of children playing is harvested to pump water for the village.
posted by KS at 10:46 AM on April 11, 2005

If you figure out a way to get more energy output than the input, let me know. I could use a few perpetual motion machines.

Waterwheels create a lot of energy, because there's a lot of energy in flowing water. Consider how much the water weighs. It's a lot.
posted by Vulpyne at 10:46 AM on April 11, 2005

this is brilliant.
posted by AbbyRoad at 10:47 AM on April 11, 2005

Let's not forget the immense amount of energy in raw materials and effort that it would take to wire every treadmill in every gym across the world.

Would it really be so very immense? To wire a bunch of devices which already, by their very nature, provide a rotary mechanism which could drive a simple dynamo? And to use some sort of accumulator/feedback system to drop power back into the local system? I'm really not convinced it would be that big a deal.
posted by Decani at 10:53 AM on April 11, 2005

Kyrademon: That power may add up, but it would still be less than the power used in total by the gym.

My father used to work with another salesman who gave a client such a good deal that they were losing money on every gasket they sold. When my dad asked him how they were going to net cash, the other salesman replied: "Volume."
posted by klangklangston at 10:54 AM on April 11, 2005

Meet the second law of thermodynamics...
posted by ozomatli at 10:55 AM on April 11, 2005

klangklangston - Of course. But the net energy saved *by and for the gyms* will not be insignificant. And in the long run, that benefits everyone.
posted by kyrademon at 11:04 AM on April 11, 2005

I'm stoked the UCB got mentioned; I was looking for verification of it, but I couldn't find any. "Didn't the UCB do this?" was the first thing that came to mind, but I wasn't sure if I was confusing it with the guy that exercised for FREEDOM!, eventually burning calories with rounds of The Deer Hunter-esque russian roulette gambling... Man, I wish they were still making new episodes.

Anywho, if you consider that most exercise machines exert resistance through friction (as far as I know) that gets converted to heat, that they then cool with A/C, it would certainly be better than that. However, the resistance (to motion) provided by a generator depends on the load on it, so there would have to be some sort of controlling mechanism. And if you consider that, the fact that the electricity will have to be converted to AC for most purposes, and the modification of all the equipment, I doubt think retrofitting existing equipment would be cost effective. It's a good idea, though, since the energy is getting spent anyway, hopefully some gym or equipment manufacturer will find a way to make it work.

Of course, as some other people have already mentioned, it's even more efficient to use the energy provided by exercising to, you know, do useful things. In other words, get your exercise activities that achieve some goal you already have rather than spending money (on membership) to spend energy (on exercise) to stay in one place (on a machine). It's odd to me that people often see exercise as a means to beauty/health rather than beauty/health being the reward for using your body frequently.
posted by nTeleKy at 11:11 AM on April 11, 2005

It's odd to me that people often see exercise as a means to beauty/health rather than beauty/health being the reward for using your body frequently.

Someone better get me some face excersizes then. And I talk all the time too...
posted by ozomatli at 11:14 AM on April 11, 2005

This might work (poorly) for bikes, but Most treadmills in gyms are motorized, and the ones that aren't frankly suck. To retrofit a treadmill to generate even more power than it consumes would probably make the whole experience suck so bad that nobody would use them anyway.
posted by willnot at 11:22 AM on April 11, 2005

I have also had this thought while running on the treadmill. It seems common for analytical people to think of the physics of their energy expenditure while staring at those numbers ...

Although it would be very costly and difficult to install, I wonder how much kinetic energy could be captured through sidewalks and roads.
posted by wrongbutton at 11:25 AM on April 11, 2005

I thought of this idea when I was a teen. I remember picturing an office building full of workers, with a set of pedals under each desk, and everyone pedalling while they worked at their computers. The entire building would be powered by their efforts, plus everyone would get exercise at the same time. Years later, I realized that it's a tad difficult to focus on technical work while doing cardio.

(Side note: I had the nick "TreeHugger" way before treehugger.com came around. And I tried to buy the domain name for my personal blog, a few years before they did, but the guy wanted a ton of cash for it. In any case, their site is groovy and I approve.)
posted by TreeHugger at 11:47 AM on April 11, 2005

How about a condom that taps into the energy created by love-friction? You could harness the power of all those people fucking.

Which would be everyone but you, of course.
posted by fungible at 11:58 AM on April 11, 2005

Seems as if this idea has been floating around for a good long while. My father has been talking about it for a number of years. Click on "Power House".
posted by anathema at 12:09 PM on April 11, 2005

Wired used this as one of their "Found: Artifacts from the Future" endpages last year - a bunch of stationary bikes in a gym with a digital readout that showed the number of watts produced. Unfortunately their online archive doesn't include Found before November of last year.
posted by Monk at 1:07 PM on April 11, 2005

If you check a little more carefully you'll notice that the non-threadmill cardio equipment (elliptical trainers, stairmasters, rowers and bikes) tend to power their own internal computers which display your speed, heart rate, etc.

So, whatever power you hope to get out of those is reduced by the amount of power required for the device to operate in the first place, so I don't think there's that much left over really.
posted by clevershark at 1:28 PM on April 11, 2005

Although it would be very costly and difficult to install, I wonder how much kinetic energy could be captured through sidewalks and roads.
posted by wrongbutton at 11:25 AM PST on April 11 [!]

Shoot, why stop there? Instead of persisting in the arcane superstition of burying our dead or wasting the bountiful potential through cremation (which uses far too much energy), why don't we just take our dead to rendering plants where they can be separated into fuel and compost? Gotta be a HUGE savings there...
posted by beelzbubba at 2:01 PM on April 11, 2005

But what will we make soylent green out of?
posted by klangklangston at 3:11 PM on April 11, 2005

There is this Huff and Puff®. The kids are usually too tired near the end of it to fully finish the ride's course.
posted by thomcatspike at 3:47 PM on April 11, 2005

How about a condom that taps into the energy created by love-friction? You could harness the power of all those people fucking.

Which would be everyone but you, of course.

Best thing on MetaFilter in days.
posted by blacklite at 5:36 PM on April 11, 2005

Sure, this sounds a bit far fetched and silly, but think of the potential applications for this principle for third world development. I recall seeing an article a couple years ago (I can no longer find the link, sorry) describing how a relief agency had developed a water pumping system powered by fun! Specifically, they had engineered a merry-go-round at a school in rural Kenya to power a pumping system to extract and store clean drinking water. The kids' excess energy was harnessed to serve the community! This meant that the women of the village no longer had to walk miles each day carting water from a neighboring village's well.
posted by pieisexactlythree at 7:13 PM on April 11, 2005

Why not take it one step further, and put a couple of wheels on these machines? People could get exercise and transport themselves to work at the same time.

Lights could be installed on these wheeled stationary cycles, powered by magnets on the spinning wheels.

Also, when people lift weights, these weights could be objects that need to be lifted.

Instead of wasting the energy spent in football, we could send trained men to fight our enemies.

Perhaps we could harness the power of "swimmers" beyond pools, employing them at beaches to rescue people.
posted by NickDouglas at 7:40 PM on April 11, 2005

I want to see a bank of rowers and bikes beside every escalator at the mall. That way I can go "work" out, whilst doing my part to better humanity. "Going up Ma'am?"
posted by sneebler at 8:58 PM on April 11, 2005

As has been noted, the power output wouldn't even come close to covering the requirements of the gym. In addition, the increased expense of maintaining the machines, not to mention the initial expense of retrofitting/replacing them all but eliminates any paltry benefit.

We would do better to reduce our energy consumption. When you consider that the amount of energy in one gallon of gasoline is approximately equivalent to 500 hours of aerobic human effort, and that millions people operate personal vehicles which frequently consume such gallons in 10 to 20 minutes, the irrelevance of such a plan becomes apparent. How many people do you think would give back even 0.01%? A precious few, I think.

Energy seems so much more important when it's our own hard work that creates it.
posted by recursive at 9:16 AM on April 12, 2005

Never mind just the lighting and air conditioning costs: what is the energy use ratio between driving, say, a 3000 lb vehicle 1.5 miles in urban traffic to the gym contrasted with the energy production of a 1 hour workout? Unless everyone walks or bikes there how can a gym ever represent anything but a massive energy sink? The minute potential for power generation in a human workout wouldn't cover the energy cost of getting the car in and out of the parking lot.
posted by George_Spiggott at 10:23 AM on April 12, 2005

Energy seems so much more important when it's our own hard work that creates it.

That's exactly it for me. I feel that my energy expenditure could do more than just keep me sweaty and fit.
posted by wrongbutton at 11:54 AM on April 12, 2005

I want to see a bank of rowers and bikes beside every escalator at the mall. That way I can go "work" out, whilst doing my part to better humanity.

Or you could take the stairs.
posted by biffa at 2:33 AM on April 13, 2005

The idea is nice. They might as well do it, but it won't accomplish a whole lot. As we stated before, each station could probably help power a couple lightbulbs. The more people you have, the more energy. Unofrtunately though, the more people there are, the more energy is needed. All told, this won't be too efficient.

My proposal for an energy efficient gym includes at 50m tall lightning pole!
posted by afrooz at 2:51 PM on April 14, 2005