3 ms·

From Google: "a beginner cyclist may average around 75–100 watts in a 1-hour workout. A fit participant will average more than 100 watts, and pro cyclists can r

From Google: "a beginner cyclist may average around 75–100 watts in a 1-hour workout. A fit participant will average more than 100 watts, and pro cyclists can reach 400 watts per hour." So 1KWh would be the output of a pro cyclist going hard for 2.5 hours, or a decently fit person biking for maybe 8 hours.

kfarr 4y ago
So generating electricity is not a lucrative career option at $2 per day
- deleted 4y ago
  [deleted]
- deleted 4y ago
  [deleted]
mrguyorama 4y ago
Obligatory cyclist powering a toaster with their bonkers thighs: https://www.youtube.com/watch?v=S4O5voOCqAQ https://www.youtube.com/watch?v=S4O5voOCqAQ IMO people often don't take the time to think about energy enough. By some quick math, I've found that the energy taken out of one 0 degree celsius ice cube to make it freeze (latent heat of fusion) is roughly equal to the energy in a ubiquitous AA battery. About 4 watt hours
- foota 4y ago
  In fairness latent heat of fusion is surprisingly high. Actually, I don't think this is quite right. A cube of water 10cm in size is 10 grams. The heat of fusion for water is 333.55 J/gram, and a AA is 14400 Joules. So the energy for the ice cube (which is 4 inches across, in imperial units) is 10 grams * 333.55 J/gram = 3335.5 Joules, which is ~1/4th of the very large ice cube.
  - mrguyorama 4y ago
    >10cm in size What about the other two dimensions? I used an ice cube containing 50ml of water, ie 50 grams. That specific number came from a quora answer where someone measured their own ice cube tray, but they seem to have giant ice cubes. Other sources mention numbers from 20ish ml to that 50ml upper bound, so I'd say the number I calculated is actually double a more reasonable answer. So a middle sized ice cube required the same energy available in an off brand, cheap-o non-alkaline chemistry AA battery. Damn, that's way less of a convenient number.

kfarr 4y ago

So generating electricity is not a lucrative career option at $2 per day

deleted 4y ago
[deleted]
deleted 4y ago
[deleted]

mrguyorama 4y ago

Obligatory cyclist powering a toaster with their bonkers thighs: https://www.youtube.com/watch?v=S4O5voOCqAQ https://www.youtube.com/watch?v=S4O5voOCqAQ IMO people often don't take the time to think about energy enough. By some quick math, I've found that the energy taken out of one 0 degree celsius ice cube to make it freeze (latent heat of fusion) is roughly equal to the energy in a ubiquitous AA battery. About 4 watt hours

foota 4y ago
In fairness latent heat of fusion is surprisingly high. Actually, I don't think this is quite right. A cube of water 10cm in size is 10 grams. The heat of fusion for water is 333.55 J/gram, and a AA is 14400 Joules. So the energy for the ice cube (which is 4 inches across, in imperial units) is 10 grams * 333.55 J/gram = 3335.5 Joules, which is ~1/4th of the very large ice cube.
- mrguyorama 4y ago
  >10cm in size What about the other two dimensions? I used an ice cube containing 50ml of water, ie 50 grams. That specific number came from a quora answer where someone measured their own ice cube tray, but they seem to have giant ice cubes. Other sources mention numbers from 20ish ml to that 50ml upper bound, so I'd say the number I calculated is actually double a more reasonable answer. So a middle sized ice cube required the same energy available in an off brand, cheap-o non-alkaline chemistry AA battery. Damn, that's way less of a convenient number.