4 ms·

I've often wondered if it would be viable to run a gym where all of the equipment is designed to harness customers' energy to help power the building. I suspect

I've often wondered if it would be viable to run a gym where all of the equipment is designed to harness customers' energy to help power the building. I suspect it wouldn't make enough of a difference to be worth it but have never seen anyone run the numbers.

jck 4y ago
Let's say a person outputs 500W and we can somehow capture all of it. That would be 10cents worth of electricity in an hour. Note that these are very generous estimates, but it does demonstrate how silly the idea of trying to generate electricity by capturing exercise output is (in a purely economic sense).
- a9h74j 4y ago
  Yes, and the Wired graphic was particularly misleading in that it showed, as I recall, multiple dollar amounts accumulating on per-session treadmill displays. On the other hand, it is possible to imagine lifestyles enhanced by various 10W contributions. 10W for heated clothing. 10W for a laptop. 10W average to power a several km electric bicycle or Aptera-size commute. And so on.
  - Flashtoo 4y ago
    This isn't exactly what you are talking about, but this art/concept for self-powered student housing came to mind: https://www.humanpowerplant.be/human_power_plant/human-powered-student-building-plans.html https://www.humanpowerplant.be/human_power_plant/human-power...
  - benj111 4y ago
    In their defense this could be seen as a type of gamification. Ultimately you can put any dollar amount on a kWh of electricity. It's the kWh generated that matters. Not saying it's a good defense though.
  - pxndxx 4y ago
    How are you proposing we produce 10W to heat clothes? we produce around 80W just by sitting idle, just wear insulating clothes! How do you produce 10W to power an electric bike? 10W is a laughable amount of power, just get rid of the electrics and pedal a bit. 10W is barely enough to charge a phone these days. Anything that gets moderately hot while in use is consuming more than 10W.
    - a9h74j 4y ago
      e.g., s/lifestyles/post-collapse lifestyles/ Based on Ali Express, heated clothing (5V power in a pocket) is popular enough in China.
- WJW 4y ago
  500W is an extremely high number as well. Pro cyclists can reach up to 400 Watt in short bursts, untrained people typically can't maintain more than 100-150W for long. We really use quite a lot of energy when measured in how many humans it would take to provide that much energy "manually".
  - anon_123g987 4y ago
    While it's true that the power of a human is not much (certainly not enough to power a house), but we have a lot of energy. Most of us carries at least 1 kg (~2 lbs) fat, which contains ~37 MJ of energy. For comparison, a stick of dynamite has ~1 MJ of energy. https://en.wikipedia.org/wiki/Fat#Biological_importance https://en.wikipedia.org/wiki/Fat#Biological_importance https://en.wikipedia.org/wiki/Dynamite#Form https://en.wikipedia.org/wiki/Dynamite#Form
    - Merad 4y ago
      > Most of us carries at least 1 kg (~2 lbs) fat It's a lot more than that. Even a fit (healthy, but not necessarily peak athletic shape) adult man will have about 15% body fat, 20% for a woman.
    - trelane 4y ago
      Why stop there? The matter itself is energy, so combine a human with an anti-human....
      - BizarroLand 4y ago
        Sweet oblivion looks just like me
  - yetihehe 4y ago
    > Pro cyclists can reach up to 400 Watt in short bursts I heard pro cyclists can reach up to 2kW. I managed to make 500W on a rowing machine for 5 minutes, but I'm a couch potato. I believe 400W is a normal rate for cyclists. When you are sitting, your body already produces about 100W of heat.
agumonkey 4y ago
A dude did that, it didn't last long, but I'm still thinking about opening one. Just to avoid the double madness of powering lights and devices so people spend energy in the air :) Even if you don't generate much, at least your biomechanical efforts are used somewhere.
- akvadrako 4y ago
  You could have them power fans or keep the lights on. Things that can use just a few watts.
  - agumonkey 4y ago
    each one yes, but if you have 20 persons averaging 100W, you can power a kettle :)
    - hinkley 4y ago
      Having been to a gym, I sincerely hope any power scavenged is use to power the ventilation system.
- benj111 4y ago
  Surely it's triple madness if you're driving to a gym to go on the running / cycling machine.
  - agumonkey 4y ago
    Oh yes I forgot to mention this :)
  - a9h74j 4y ago
    Not just driving to the gym, but driving twice around the parking lot to find a closer space for a shorter walk. And wasn't it Mumford who observed that given the time it takes to earn the money to buy a car, on average it can be faster to walk than to drive.
CodeBeater 4y ago
As a quasi sidenote, most gyms already implement this on a smaller scale on their elliptical and spinning machines as they're usually self powered and you can regulate the resistance the machine offers, which I assume must increase or decrease the number of magnets around the flywheel.
- adwww 4y ago
  However, most energy you burn in a gym is converted into heat energy, which the gym then burns extra electricity trying to air condition.
SenHeng 4y ago
The Grand Tour has tried to answer that question. I thought the turnstiles idea was really good, especially if you place them in a building with heavy traffic. Though probably not really cost effective. https://www.youtube.com/watch?v=WhwyH6tT-EQ https://www.youtube.com/watch?v=WhwyH6tT-EQ

jck 4y ago

Let's say a person outputs 500W and we can somehow capture all of it. That would be 10cents worth of electricity in an hour. Note that these are very generous estimates, but it does demonstrate how silly the idea of trying to generate electricity by capturing exercise output is (in a purely economic sense).

a9h74j 4y ago
Yes, and the Wired graphic was particularly misleading in that it showed, as I recall, multiple dollar amounts accumulating on per-session treadmill displays. On the other hand, it is possible to imagine lifestyles enhanced by various 10W contributions. 10W for heated clothing. 10W for a laptop. 10W average to power a several km electric bicycle or Aptera-size commute. And so on.
- Flashtoo 4y ago
  This isn't exactly what you are talking about, but this art/concept for self-powered student housing came to mind: https://www.humanpowerplant.be/human_power_plant/human-powered-student-building-plans.html https://www.humanpowerplant.be/human_power_plant/human-power...
- benj111 4y ago
  In their defense this could be seen as a type of gamification. Ultimately you can put any dollar amount on a kWh of electricity. It's the kWh generated that matters. Not saying it's a good defense though.
- pxndxx 4y ago
  How are you proposing we produce 10W to heat clothes? we produce around 80W just by sitting idle, just wear insulating clothes! How do you produce 10W to power an electric bike? 10W is a laughable amount of power, just get rid of the electrics and pedal a bit. 10W is barely enough to charge a phone these days. Anything that gets moderately hot while in use is consuming more than 10W.
  - a9h74j 4y ago
    e.g., s/lifestyles/post-collapse lifestyles/ Based on Ali Express, heated clothing (5V power in a pocket) is popular enough in China.
WJW 4y ago
500W is an extremely high number as well. Pro cyclists can reach up to 400 Watt in short bursts, untrained people typically can't maintain more than 100-150W for long. We really use quite a lot of energy when measured in how many humans it would take to provide that much energy "manually".
- anon_123g987 4y ago
  While it's true that the power of a human is not much (certainly not enough to power a house), but we have a lot of energy. Most of us carries at least 1 kg (~2 lbs) fat, which contains ~37 MJ of energy. For comparison, a stick of dynamite has ~1 MJ of energy. https://en.wikipedia.org/wiki/Fat#Biological_importance https://en.wikipedia.org/wiki/Fat#Biological_importance https://en.wikipedia.org/wiki/Dynamite#Form https://en.wikipedia.org/wiki/Dynamite#Form
  - Merad 4y ago
    > Most of us carries at least 1 kg (~2 lbs) fat It's a lot more than that. Even a fit (healthy, but not necessarily peak athletic shape) adult man will have about 15% body fat, 20% for a woman.
  - trelane 4y ago
    Why stop there? The matter itself is energy, so combine a human with an anti-human....
    - BizarroLand 4y ago
      Sweet oblivion looks just like me
- yetihehe 4y ago
  > Pro cyclists can reach up to 400 Watt in short bursts I heard pro cyclists can reach up to 2kW. I managed to make 500W on a rowing machine for 5 minutes, but I'm a couch potato. I believe 400W is a normal rate for cyclists. When you are sitting, your body already produces about 100W of heat.

agumonkey 4y ago

A dude did that, it didn't last long, but I'm still thinking about opening one. Just to avoid the double madness of powering lights and devices so people spend energy in the air :) Even if you don't generate much, at least your biomechanical efforts are used somewhere.

akvadrako 4y ago
You could have them power fans or keep the lights on. Things that can use just a few watts.
- agumonkey 4y ago
  each one yes, but if you have 20 persons averaging 100W, you can power a kettle :)
  - hinkley 4y ago
    Having been to a gym, I sincerely hope any power scavenged is use to power the ventilation system.
benj111 4y ago
Surely it's triple madness if you're driving to a gym to go on the running / cycling machine.
- agumonkey 4y ago
  Oh yes I forgot to mention this :)
- a9h74j 4y ago
  Not just driving to the gym, but driving twice around the parking lot to find a closer space for a shorter walk. And wasn't it Mumford who observed that given the time it takes to earn the money to buy a car, on average it can be faster to walk than to drive.

CodeBeater 4y ago

As a quasi sidenote, most gyms already implement this on a smaller scale on their elliptical and spinning machines as they're usually self powered and you can regulate the resistance the machine offers, which I assume must increase or decrease the number of magnets around the flywheel.

adwww 4y ago
However, most energy you burn in a gym is converted into heat energy, which the gym then burns extra electricity trying to air condition.

SenHeng 4y ago

The Grand Tour has tried to answer that question. I thought the turnstiles idea was really good, especially if you place them in a building with heavy traffic. Though probably not really cost effective. https://www.youtube.com/watch?v=WhwyH6tT-EQ https://www.youtube.com/watch?v=WhwyH6tT-EQ