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A lightning bolt would be worth only about a nickel (2015)

engineering.mit.edu

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Re: A lightning bolt would be worth only about a nickel (2015)

#11

Post by agumonkey »

NoboruWataya wrote: post #3
a9h74j wrote: post #2

This reminds me of an old (misleading) graphic in Wired magazine suggesting that people on treadmills could be significantly reducing their electricity bills.

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.

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.

Re: A lightning bolt would be worth only about a nickel (2015)

#12

Post by teraflop »

typedef_struct wrote: post #4

TIL one gallon of gas is 120 lightning bolts, and the relative cost of energy between electricity and fuel is near equilibrium.

To illustrate that even more vividly: if a typical lightning bolt is a few km long, the energy released is equivalent to detonating a stream of gasoline roughly 0.1mm in diameter (not much thicker than a human hair).

Re: A lightning bolt would be worth only about a nickel (2015)

#13

Post by CodeBeater »

NoboruWataya wrote: post #3
a9h74j wrote: post #2

This reminds me of an old (misleading) graphic in Wired magazine suggesting that people on treadmills could be significantly reducing their electricity bills.

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.

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.

Re: A lightning bolt would be worth only about a nickel (2015)

#14

Post by akvadrako »

agumonkey wrote: post #11
NoboruWataya wrote: post #3

Earlier quoted context omitted.

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.

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.

You could have them power fans or keep the lights on. Things that can use just a few watts.

Re: A lightning bolt would be worth only about a nickel (2015)

#15

Post by WJW »

jck wrote: post #5
NoboruWataya wrote: post #3

Earlier quoted context omitted.

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.

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).

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".

Re: A lightning bolt would be worth only about a nickel (2015)

#16

Post by joosters »

Lightning-powered bitcoin mining is obviously the next big thing for green energy!

Now you need a double helping of luck - first that you get struck by lightning, and second that your miner guesses the right hash to make a block. But maybe the two somehow combine? After all, people who survive a lightning strike are said to be so lucky that they should buy a lottery ticket... so following this logic, lightning powered mining would be extra efficient!

Now I'm off to patent my new PoS invention - proof of strike :)

Re: A lightning bolt would be worth only about a nickel (2015)

#18

Post by benj111 »

agumonkey wrote: post #9
a9h74j wrote: post #2

This reminds me of an old (misleading) graphic in Wired magazine suggesting that people on treadmills could be significantly reducing their electricity bills.

It would because people would become very aware of the energy sinks and its cost :) Some city noticed changes in consumption when new houses had meter installed on ground floor rather than in the basement.

In the UK they're rolling out smart meters that have a display that show real time usage.

They're advertised as saving energy which I think is a bit misleading as it's only based on this phenomena

Re: A lightning bolt would be worth only about a nickel (2015)

#19

Post by joosters »

teraflop wrote: post #12
typedef_struct wrote: post #4

TIL one gallon of gas is 120 lightning bolts, and the relative cost of energy between electricity and fuel is near equilibrium.

To illustrate that even more vividly: if a typical lightning bolt is a few km long, the energy released is equivalent to detonating a stream of gasoline roughly 0.1mm in diameter (not much thicker than a human hair).

When you phrase it like that, it does feel like the quoted energy figure is too low - after all, lighting that tiny a stream of gasoline isn't going to illuminate the sky anywhere as bright as a lightning bolt.

Perhaps the 'nickel of electricity' is what's remaining in electrical energy after all the rest has been used up as light, heat and sound across the sky?

Re: A lightning bolt would be worth only about a nickel (2015)

#20

Post by benj111 »

a9h74j wrote: post #6
jck wrote: post #5

Earlier quoted context omitted.

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).

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.

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.

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